Skip to main content
ADxS.org

4. Psychological Risk Factors for ADHD

4. Psychological Risk Factors for ADHD

Last updated:

Author: Ulrich Brennecke
Review: Waldemar Zdero, M.A. in Psychology

Traumatic experiences, as well as stressful experiences that cause significant distress but fall below the threshold for trauma, are risk factors for ADHD. Social risk factors increase the risk of ADHD.12
Severe stress experienced by the mother during the early years of a child’s life causes significant epigenetic changes in the child’s DNA.3

Stress during adolescence and childhood is a common cause of later mental health problems.4 For example, early childhood stress permanently alters the expression of corticosteroid receptors and, consequently, the HPA axis’s response to acute and chronic stress.5 A comprehensive overview of the effects of early childhood stress and its epigenetic manifestations can be found in Eckerle.6

Early childhood or chronic stress, including traumatic experiences, also plays a role in the development of ADHD. Children who experience early childhood trauma—such as maltreatment, sexual abuse, separation from a primary caregiver, hostile behavior by parents, or wartime experiences—are more likely to develop ADHD symptoms. Conversely, research shows that people with ADHD have experienced a significantly higher number of traumatic events, particularly in the context of relationships.
Traumatic experiences can cause lasting changes to the dopaminergic system in the brain, thereby increasing the risk of ADHD.#

4.1. Growing Up in a Children’s Home (+200% to +500%)

Children who were exposed to their mothers’ prenatal use of multiple drugs and who subsequently grew up in foster care were found to have a threefold increased risk of ADHD (+200%) between the ages of 17 and 227, corresponding to a prevalence of about 20%.89 In U.S. child welfare agencies, the prevalence of ADHD is 19%, representing a nearly fourfold increase (+300%)10
27% of former children in residential care in Bucharest had ADHD at age 4.5, at age 12, or at both ages.
Ten years later, 77.6% of Norwegian children in foster care—now young adults—exhibited at least one current mental Disorder:11

  • PTSD (42.1%)
  • Agoraphobia (33.3%)
  • social phobia (27.9%)
  • severe depressive episode (23.1%)
  • specific phobia (21.1%)
  • ADHD (19.2%)
    • in the case of a

Another study found no increased prevalence of ADHD (5.8%) in residential facilities without deprived living conditions, but a significantly higher prevalence of ADHD12 —nearly 4 to 7 times higher (19% to 29.3%, +300% to +600%) among children who had grown up for six months or longer under the harsh living conditions of Romanian orphanages.13
The later an adoption from a children’s home took place, the higher the prevalence of ADHD was.141516

4.2. Trauma as a Cause of ADHD

4.2.1. Chronic Stress and Trauma in Early Childhood as a Risk Factor for ADHD (up to +420%)

Early childhood stress and chronic stress (neglect, deprivation, abuse, trauma) increase the risk of ADHD.1729181920212223

Numerous studies confirm a disproportionately high prevalence of early-life trauma among people with ADHD compared to people without the condition.2425 26 27 28 29 30 31 32 33 34 35 There is ongoing debate as to whether this represents a causal relationship or whether the symptoms of ADHD and trauma simply overlap.3637
Trauma is generally described as a contributing factor to mental health problems.3839
Epidemiological data show that ADHD is associated with a significantly increased level of psychological stress. The functional changes observed in ADHD and PTSD are very similar. Various processes associated with stress-related disorders are likely to play a crucial role in the etiology and pathogenesis of ADHD. Traumatic experiences or chronic stress during childhood are major risk factors for severe mental health problems in adolescence or adulthood and are associated with neurobiological changes that impair attention, cognition, and emotional regulation.40

Another potential pathway for the development of ADHD is considered to be the interaction of early childhood trauma with genetic factors.41 A combination of a low-activity MAO-A gene variant, traumatic childhood experiences, and exposure to certain toxins—which in turn reduce MAO-A expression—significantly increases the risk of ADHD.42
Children of mothers who had experienced trauma in early childhood had an increased risk of ADHD.43

ADHD differs from early childhood trauma:44

  • more masculine
  • higher nvIQ scores
  • more attention problems
  • fewer physical symptoms
  • externalizing behaviors of equal severity

Positive childhood experiences can foster resilience and offset ACEs. However, evidence suggests that more frequent ACEs are often accompanied by fewer positive childhood experiences.45

4.2.2. Types of Stress and Trauma in ADHD

In rats, the stress caused by early separation from their mothers led to hyperactivity and inattention, which were alleviated by MPH.46
Childhood maltreatment is associated with an increased risk of ADHD in adults.4748 49 50 51 52 Children with ADHD are more likely to have experienced abuse.53
Girls with ADHD were three times as likely to have experienced abuse as those without ADHD54; another study also found that children with ADHD were three times as likely to have experienced abuse, as well as twice the rate of physical abuse and two and a half times the rate of emotional abuse.55 Child maltreatment, particularly emotional maltreatment, is also correlated with increased emotional dysregulation and reactivity.47 Emotional abuse and physical maltreatment significantly increase the risk of ADHD and ADHD symptoms, as do adverse living conditions and school anxiety.56 Trauma resulting from emotional neglect or abuse significantly increased the likelihood of ADHD.57

Many children and adults with ADHD report sexual abuse and/or other types of trauma.58 ADHD symptoms correlate with sexual and physical abuse occurring before the age of 16 or 175960 Commercial sexual exploitation (child prostitution, child pornography, child sex tourism, child trafficking) is associated with an increased risk of ADHD and CD.61
The number of early childhood injuries correlated with the risk of developing ADHD later in life.62 It remains unclear whether the injuries were a manifestation of early ADHD—since ADHD correlates with dyspraxia and motor development delays—or whether they were the cause of the later ADHD.

A study found a highly significant increase in the frequency of traumatic experiences among people with ADHD.63 While the frequency of non-interpersonal events was barely elevated, that of interpersonal events was massively higher compared to people without ADHD. For more on this, see ⇒ Trauma as a Cause of ADHD.
Traumatic experiences are intense stressful experiences in the broad sense, e.g.:

  • Frequent separation from the primary caregiver without a substitute
  • Deprivation (an emotionally deficient relationship between parents and child)
  • hostile or neglectful behavior by the parents toward the child
  • Long-standing conflicts between parents / marital problems
  • Loss of parents64
  • War experiences
    A study of preschool-aged children of refugees from war-torn regions showed that they were “more restless,” had an overwhelming urge to move, and had more difficulty concentrating. At the same time, they were described as being so traumatized that even a hot glue gun would make them cry. 65
  • Shocks (e.g., noise shock)
  • Ultimately, it can be any event associated with a subjective sense of loss of control and/or a threat to one’s life

A study of 110 boys found a highly significant increase in the prevalence of traumatic experiences among people with ADHD.63
The Life Incidence of Traumatic Events (LITE-P) test asks about:

  1. Child was in a car accident
  2. Child injured in another accident or in the hospital
  3. A close relative was injured
  4. Family Member in the Hospital
  5. Death of a Family Member
  6. A friend is sick or has died
  7. Child Survived a Fire
  8. Child Experienced a Natural Disaster
  9. Mutual Injury/Destruction of Property Between Adults
  10. Separation / Divorce of Parents
  11. Child Abuse
  12. Child tied up / locked up
  13. Child Abuse
  14. Child Threatened
  15. Child Robbed

On average, the 65 boys with ADHD had experienced nearly every type of trauma more frequently than the 45 boys in the comparison group. Interpersonal events (traumas in the context of relationships) were significantly more prevalent among the boys with ADHD than among people with ADHD, even more so than non-interpersonal events. The number of relationship-related IPE traumas also correlates with the intensity of hyperactivity and overall symptoms. When adjusted for age, inattention symptoms also correlate highly significantly with the number of IPE traumas.
Several other studies have reached similar conclusions.6667

The loss of a friend to death increased the risk of ADHD among adolescents by 18%.68

A natural disaster during early childhood increased the risk of ADHD.69
Forced eviction from one’s home, as a stressful experience, was associated with increased levels of depression and anxiety, but not with increased levels of ADHD.70

Unpredictable or inconsistent rules or cues from parents or caregivers are another cause of early childhood stress. An increased prevalence correlates with a higher likelihood of a mental health diagnosis (ADHD, anxiety, depression, externalizing problems, sleep disorders) or a physical health diagnosis (obesity, abdominal pain, asthma, headaches). Including unpredictable or contradictory rules or signals in the stress screening (QUIC-5) can help explain risks for depression, obesity, and sleep disorders that were overlooked by previous screening methods (PEARLS).71

In contrast, one study reports that victimizing trauma increased the likelihood of ODD, but not of ADHD.72

A person with ADHD-HI:
My mother is definitely a person with ADHD-HI. Even so, I always felt truly loved by my parents and my grandmother, who was my primary caregiver.
My family says that as a baby (a much-wanted child), I was a ray of sunshine: cheerful, a good sleeper—everything was wonderful. That is, until I suffered a noise shock at age 2½ (New Year’s Eve firecrackers right outside the bedroom window). My parents claim that I didn’t sleep at all for three months after that. Whether that’s true or not—according to their accounts, from that point on I was difficult and anxious. In particular, I would crawl trembling under tables whenever I heard jet fighters (which back then could still break the sound barrier and thus produced an enormous boom). During nighttime thunderstorms, I would flee in a panic to my parents’ bed until I was 12 or 14. Falling asleep was a struggle for decades.

4.2.3. Quantitative Link Between Trauma and ADHD

The number of stressful life events (as measured by the Traumatic Events Screen Inventory for Children) correlated with more severe ADHD.73 The number of Adverse Childhood Experiences (ACEs) increased the risk of ADHD:74

  • 1 ACE: 2.1 times the risk of ADHD
  • 2 ACEs: 4.5 times the risk of ADHD
  • 3 or more ACEs: 5.2 times the risk of ADHD
  • The scores for ADHD symptoms were higher in cases of sexual abuse, emotional and physical neglect, and bullying.

Children with ADHD were more frequently affected by all types of adverse childhood experiences (ACEs) and were more likely to have 1 to 4 or more ACEs than children without ADHD. Children with 4 or more ACEs had a 3.44-fold increased risk of ADHD (+244%; aOR: 3.44) compared to children without ACEs. Boys, children in moderate or poor health, and children in rural areas were more likely to receive an ADHD diagnosis, while children of color and uninsured children were less likely to receive an ADHD diagnosis.75
The number of childhood traumas experienced between the ages of 5 and 9 increased the risk of ADHD at age 9 (cohort study, n = 1,572):76

  • 1 trauma: 1.9 times the risk of ADHD (+90%)
  • 2 traumatic events: 2.1-fold increased risk of ADHD (+110%)
  • 3 traumatic events: 2.2 times the risk of ADHD (+120%)

The number of childhood traumas increased the risk of ADHD in children aged 6 to 17 (with family-related traumas carrying slightly more weight):77

  • 1 trauma: 1.71-fold risk (+71%)
  • 2 or more traumatic events: 2.97-fold risk (+197%)

Children with 0 to 3 positive childhood experiences had a 37.6% lower risk of ADHD than children with 4 or more positive childhood experiences (e.g., the feeling that your family stood by you during difficult times; the feeling of being supported by friends; the feeling of belonging at school; the opportunity to talk to your family about your feelings)77

The number of traumatic experiences correlates with the severity of ADHD7879 as well as with the risk of ADHD.
Early-life trauma (ACE) increased80

  • Hyperactivity and inattention are more pronounced in women than in men
  • Hyperactivity and inattention are roughly equally prevalent in women
  • Hyperactivity is more pronounced in men than inattention
  • Aggression in women, as manifested by ADHD symptoms

ADHD symptoms correlate with:81

  • K-SADS-PL scores for post-traumatic stress disorder among 14- and 15-year-olds82

A Chinese study found that 48.6% of children with clinical ADHD had experienced childhood trauma, compared with 9.4% of children whose ADHD symptoms did not meet clinical criteria (5.17-fold risk, +417%).83
A Swedish cohort study found that people with ADHD experienced traumatic life events 1.8 times more frequently than people without ADHD (+80%).84

The risk for children to develop ADHD (odds ratio) increases with the level of psychosocial stress (Rutter Indicator, RI). For an RI of 1, the odds ratio is 7; for an RI of 4, it is 41.7.85
Odds ratios greater than 1 indicate a multiplication of the risk. An OR of 2 means the risk is doubled, and an OR of 3 means the risk is tripled.
Disorganized attachment behavior is a risk factor for ADHD.86 Attachment disorders in children during their early years, when combined with a corresponding genetic predisposition, lead to activation of the DRD4 gene, which is also common in ADHD.87

Severe stress experienced by the mother during the early years of a child’s life causes significant epigenetic changes in the child’s DNA.3

Between 20% and 50% of all children who experience early childhood trauma develop clinical ADHD symptoms.178889

Assuming that one-third90 to one-half of all children and two-thirds of all children in psychiatric samples have experienced trauma, a frequent overlap between ADHD and early childhood trauma is to be expected.91 However, this alone does not explain why studies on trauma as a (contributing) cause of ADHD have consistently found a higher number of early-life traumas among people with ADHD than among people without the disorder.92

Since ADHD correlates with a stimulus filter that is too open—which, on the one hand, may be a consequence of stress dysregulation, but on the other hand can also be understood as a manifestation of the genetic predisposition to ADHD (high sensitivity), the question arises as to whether early childhood stress, which manifests as ADHD, might not be understood as a low-threshold form of trauma in highly sensitive individuals. It can be assumed that multiple early childhood traumas, in the presence of a corresponding genetic predisposition, can trigger ADHD. The more sensitive a person is, the smaller the impact of a threatening stress situation needs to be to neurologically trigger a traumatic manifestation of stress regulation dysfunction.
It is well known that different personality types react to environmental influences to varying degrees. Introverts react more intensely to environmental influences than extroverts.93 Aron’s concept of high sensitivity is closely linked to introversion.

This raises the question of whether such low-threshold trauma experienced by people with ADHD—which, to stick with this analogy, typically occurs during the first six years of life—is even amenable to therapeutic intervention and analysis.

The

  1. People’s poor memory of events during their early years, on the one hand, and
  2. the fact that even impacts far below what unaffected individuals would consider a serious potential cause of trauma can trigger a traumatic reaction in people with a corresponding genetic predisposition; on the other hand,

could obscure our view of such a cause.

Based on this line of thinking, the principles of EMDR therapy—which is recognized as effective for treating trauma—could be applicable to ADHD.

In cases of trauma and PTSD, there is partial overactivation of the PFC, which can be effectively reduced through bilateral sensory stimulation in EMDR; this reduction correlates with the degree of reduction in PTSD symptoms.94

People with ADHD are disproportionately likely to be victims of violence and bullying as a consequence of their ADHD.95

4.2.4. PTSD (up to +153%)

  • 2.53-fold increased risk of ADHD (+153%) among war veterans with a history of PTSD96
  • 2.19-fold increased risk of ADHD (+119%) among war veterans with existing PTSD96

The functional changes associated with ADHD and PTSD are very similar. Various processes involved in stress-related disorders are likely to play a crucial role in the etiology and pathogenesis of ADHD. Traumatic experiences or chronic stress during childhood are major risk factors for severe mental health problems in adolescence or adulthood and are associated with neurobiological changes that impair attention, cognition, and emotional regulation.40

4.2.5. Stressful experiences during childhood and early adolescence lead to persistent ADHD in adulthood

A study of stress levels in children with ADHD found that high stress levels during childhood and adolescence were associated with a severe course of ADHD-HI or ADHD-I into adulthood, whereas children with low stress levels during childhood and adolescence often exhibited a remitting course of ADHD (both ADHD-HI and ADHD-I).97

4.2.6. Traumatic Experiences and Dopamine

Although it has not yet been definitively established that (early childhood) trauma (causally) increases the risk of ADHD through changes in the dopaminergic system, there is strong evidence that trauma occurring in early childhood as well as during adolescence permanently alters the brain’s dopaminergic system.9899 100 101 One possible mechanism is that stress alters the HPA axis, which in turn influences dopamine synthesis and dopamine receptors.102

The most important dopaminergic nodes of the brain’s stress network are:

Rodents show the following signs after early stress:

  • blunted dopamine stress response in the mPFC107108
  • elevated tonic dopamine levels in subcortical regions109
  • increased norepinephrine release in response to acute stress107

Early-life stress appears to cause an increased dopamine stress response in the striatum later in life110111

In humans, the dopaminergic system is primarily regulated by dopamine D2 and D3 receptors in most nodes of the stress network.112113114

Childhood trauma was significantly positively correlated with the availability of D2 receptors in men, while it tended to be negatively correlated in women.115

Early-life trauma is associated with reduced levels of homovanillic acid, a dopamine metabolite, in blood plasma116 and in cerebrospinal fluid117.
A study reports a correlation between the spatial extent of dopamine activity in the mPFC during acute stress and the severity of the stressful experience in early or later childhood.118

4.2.7. Childhood Trauma in Other Clinical Conditions

Traumatic experiences in childhood also increase the risk of other disorders such as schizophrenia119 and psychosis.120 Trauma is generally described as a contributing factor to mental health problems.3839

4.2.8. The more traumatic experiences, the more common it is to be a non-responder to medication

People with ADHD for whom ADHD medications were ineffective (nonresponders) reported higher levels of trauma on the Perceived Stress Scale (PSS) than people with ADHD for whom medications were effective (responders).121

Among those not affected, the number of traumatic childhood events correlated with the level of currently experienced stress, as well as with a stronger dopamine response in the ventral striatum to amphetamine.115
This could be an indication that increased childhood trauma is associated with an increased striatal dopamine response to stimulants, meaning that a significantly lower dose of stimulants would be more appropriate for these people with ADHD. We can immediately think of people with ADHD to whom this applies.

4.3. Growing Up in Foster Care (+200%)

A study of Chinese adopted girls found an ADHD rate of 16.7%, which is roughly three times the usual prevalence.122 Whether this is a consequence of the adoption or a consequence of the biological parents’ problems—which were also the reason for the children being placed for adoption—remains unclear. There would be strong evidence supporting the influence of the latter factor if the ADHD prevalence did not correlate with the length of time spent in an orphanage prior to adoption.

4.4. Starting school relatively earlier / older classmates (+34%)

The youngest children in a class have a 30% higher risk of ADHD than the oldest children in the same class. A study of over 400,000 children in the U.S. showed that in states where a fixed age as of September 1 determines school enrollment, among children born in August—who thus reached school age immediately before the cutoff date— 0.85% had an ADHD diagnosis (+35%) and 0.52% were receiving ADHD medication, whereas among children born in September—who were, on average, 11 months older— only 0.63% had an ADHD diagnosis and 0.4% were receiving ADHD medication. In states where school enrollment was not determined by a fixed age as of a specific cutoff date, children born in August still had a slightly higher rate of ADHD compared to those who were 11 months older; however, the difference was no longer 0.21 percentage points but 0.08 percentage points.123
Similarly, a meta-analysis of three Brazilian cohort studies involving 8 million participants and 164,000 people with ADHD found that children in a class who were among the youngest 4 months had a 34% increased risk of ADHD.124 A study of 1,042,106 English children between the ages of 4 and 15 reached similar conclusions.125 The risk of depression and intellectual disability increased in parallel with that of ADHD.
A French registry study (n = 58 million) found that the youngest children and adolescents in a class were more likely to receive an ADHD diagnosis and be prescribed methylphenidate.126 Delaying entry into (preschool) or school by one year dramatically reduced inattention and hyperactivity in the following year (effect size = 0.73). The effect was primarily observed in girls and persisted until the age of 11.127
A meta-analysis (19 studies from 13 countries involving n = 15.4 million children) confirmed that the relatively youngest children in a class have an increased risk of ADHD (17 out of 19 studies) and suggested that the reason for the lack of effect in Denmark was the later school enrollment of children with developmental deficits, a practice common there.128

A Danish study (n = 418,396) found no association between the age of children within a school grade and (more frequent / less frequent) ADHD medication use. The authors attributed this, among other things, to the low prevalence of ADHD, clear diagnostic criteria, and strict requirements for prescribing ADHD medications in Denmark, and they cited studies from countries with high ADHD prevalence where differences were observed.129

The findings of this study are partly consistent with those of a Canadian study, which found that successful ice hockey players were disproportionately likely to be among the older children in their class. The same pattern was observed among Belgian soccer players, among whom the birth dates of the most successful players were, for a long time, predominantly in August and September because the cutoff date for determining age for player selection in a given age group was August 1. After this cutoff date was moved to January 1, the most successful players were most often born in January and February. Another study confirmed this “relative age effect” across Europe.130
This effect is likely due, in part, to selection criteria. However, this could only explain the differences among athletes that may arise from varying levels of support. The parallel with ADHD, however, suggests that there may also be an effect of the developmental lever of opportunity/risk genes.

It is unclear how these differences relate to ADHD.

One hypothesis on this matter is that younger children, due to their naturally more immature behavior, are pathologized to a greater extent than average by the teachers evaluating them.131

Another hypothesis suggests that behavioral problems are less a social consequence of being relatively young within a class than an absolute consequence of early school entry in general. However, this study found no difference in ADHD.132 In our view, it also stands to reason that younger children are more likely to start school too early than older children. The extent to which this influences ADHD remains unclear.
A meta-analysis found that a younger relative age was not statistically significantly associated with the persistence of ADHD at a 4-year follow-up.133
A cohort study of n = 8,508 participants in the Twins’ Early Development Study found a relative age effect on English test scores (but not on math scores) as well as on most parent and teacher ratings of ADHD symptoms, particularly during middle childhood. The polygenic risk score did not correlate with relative age.134

Our hypothesis is that being among the youngest (and thus the most vulnerable) in a class could also constitute a psychological burden. It is well known that a low social status is a significant stressor. To our knowledge, no studies have yet been conducted to determine whether or to what extent this influences ADHD diagnoses among schoolchildren.

4.5. Growing Up in a Dysfunctional Neighborhood

Children who grow up in a dysfunctional neighborhood or dysfunctional urban environment are at increased risk for ADHD. Interestingly, this appears to be less of a factor among Black children.135

In the bivariate analysis, higher levels of poverty in the neighborhood were associated with higher levels of parent-reported ADHD and lower levels of parent-reported medication use. In the multivariate analysis, poverty no longer correlated with ADHD, but medication use still correlated negatively with ADHD.136

4.6. Class size

A study found that in Korea, larger class sizes were associated with a lower rate of ADHD. It was hypothesized that in larger classes, hyperactive, impulsive, inattentive, or disorganized children are less noticeable, suggesting that class size does not influence the development of ADHD but rather its detection.137
In contrast, another study found that teachers in the U.S. are more likely to notice signs of ADHD in larger classes and therefore diagnose ADHD more frequently than in smaller classes.138
A French study suggests that a higher level of stimulation (noise, visual distractions, large class sizes) may reveal or exacerbate instability, impulsivity, and inattention, thereby making ADHD more apparent.139
The impact of class size on the incidence or diagnostic prevalence of ADHD is therefore unclear.

4.7. Low Educational Attainment and ADHD Are Mutually Causal

A large registry study in the Netherlands (n = 1.7 million) found evidence that low educational attainment is a contributing factor in the development of ADHD, and that ADHD is a contributing factor in low educational attainment.140

4.8. Media

4.8.1. Early Television Viewing

Early television viewing at ages 1 and 3 was associated with attention problems at age 7.141142 Early television viewing at 18 months was associated with ADHD and ASD symptoms during the preschool years.143

It is worth questioning whether high television viewing by children at an early age is a causal factor in attention problems, or whether parents with limited ability to provide attention—due to their own mental health issues (e.g., their own ADHD)—are more likely to leave their children to their own devices and park them in front of the TV. In the latter case, television viewing would merely be a correlation and not necessarily a causal factor for ADHD. This is because—as will be described below—there are countless studies showing that an attentive, warm, and secure attachment style can prevent ADHD even in the presence of a genetic predisposition.
So while it is well established that close parental attention provides good protection against ADHD, there are no known studies indicating that limiting television viewing prevents ADHD.
From our perspective, the more logical connection is that heavy television viewing—as a substitute for personal attention—correlates with a lack of personal attention. It also seems plausible that watching television and using the Internet to access age-inappropriate content can cause further harm.

A study found evidence that watching more than 3 hours of television per day at age 3 was causally linked to an increase in ADHD symptoms at age 5, compared to watching 1 to 3 hours. It is also possible that completely avoiding television viewing increased ADHD symptoms.144
There should be no doubt that media consumption of more than 3 hours a day is inappropriate for 3-year-olds.

4.8.2. Media Consumption and ADHD

Correlation studies:

It is likely that ADHD, hyperactivity, and impulsivity (possibly in the parents) are causal factors behind problematic media use.145 Nevertheless, increased screen time in children appears to be able to impair attention.146
A study found that children with ADHD had 50% higher media consumption (183 minutes vs. 117 minutes).147

In contrast, one study reported that increased cell phone use raised the risk of ADHD by 83% and increased television viewing time raised the risk of ADHD by 110%, while ADHD had no effect on the amount of time spent using media.148
Computer or tablet use lasting more than 4 hours and television viewing lasting more than 2 hours were associated with an increased risk of ADHD.149
It has also been reported that screen time exceeding 4 hours in children under 6 years of age can cause “virtual autism.” However, this condition is said to subside once screen time is reduced.150
High media consumption was associated with a 94% increased risk of ADHD (k = 6, n = 3,853) and an SMD of 0.07 (meta-analysis, k = 9, n = 22,235).

Daily television viewing of more than 5 hours among children was associated with a 63-fold increased risk of ADHD.151

A Japanese study found evidence that increased media consumption is a consequence of neurodevelopmental disorders such as ADHD and ASD, rather than the underlying cause.152

However, the findings mentioned so far only reflect correlations; in other words, they do not indicate whether ADHD is a consequence of screen use or whether screen use is a consequence of ADHD.

Causality studies:
A study that used Mendelian randomization analysis on pooled data from global genome-wide association studies to investigate the possible causal relationship between leisure-time screen time and the risk of neurodevelopmental disorders found that each standard deviation increase in leisure-time screen use reduced the risk of ADHD by 32%. In contrast, the risk of intellectual disability increased by 51%.153

4.8.3. Duration of Online Social Activities

The amount of social media use had no effect on ADHD. Only media addiction was associated with elevated ADHD scores.154
Using data from the Adolescent Brain Cognitive Development (ABCD) study, the association between the duration of online social activities (OSA time) and ADHD symptoms was examined in a longitudinal study. Longer OSA time was associated with more ADHD symptoms in early adolescence (only among girls), whereas more ADHD symptoms did not predict longer OSA time. Only among boys was there an association between ADHD symptoms and longer OSA time.155
Not only did children with ADHD show increased social media use, but so did their parents.156 This could indicate a genetic mediating factor.

4.9. Transgender

Transgender individuals appear to be at a higher risk for ADHD.157

Among n = 34 people with gender dysphoria—that is, who suffered psychologically from being born with the “wrong” gender—the prevalence of ADHD was 50% and the prevalence of major depression was 64.7%. 158

4.10. Psychological Factors Not Associated with an Increased Risk of ADHD

Growing up bilingual did not increase the risk of ADHD.159

4.11. Psychological Factors Associated with a Reduced Risk of ADHD

  • When parents have immigrant status, this is associated with a reduced risk of ADHD160 within the first two generations.161
  • Positive childhood experiences were associated with a reduced risk of ADHD. Children who had volunteered in their community had a 13% lower risk of ADHD.162

  1. Rigdon, Montez, Palakshappa, Brown, Downs, Albertini, Taxter (2022): Social Risk Factors Influence Pediatric Emergency Department Utilization and Hospitalizations. J Pediatr. 2022 Jun 10:S0022-3476(22)00537-6. doi: 10.1016/j.jpeds.2022.06.004. PMID: 35697140. ↥

  2. Jendreizik LT, von Wirth E, Döpfner M (2022): Familial Factors Associated With Symptom Severity in Children and Adolescents With ADHD: A Meta-Analysis and Supplemental Review. J Atten Disord. 2022 Nov 3:10870547221132793. doi: 10.1177/10870547221132793. PMID: 36326291. METASTUDIE ↥ ↥

  3. Essex, Boyce, Hertzman, Lam, Armstrong, Neumann, Kobor (2013): Epigenetic Vestiges of Early Developmental Adversity: Childhood Stress Exposure and DNA Methylation in Adolescence; Child Dev. 2013 Jan; 84(1): 58–75. doi: 10.1111/j.1467-8624.2011.01641.x ↥ ↥

  4. Rensing, Koch, Rippe, Rippe (2006): Mensch im Stress; Psyche, Körper, Moleküle; Elsevier (inzwischen Springer); Seite 23 ↥

  5. Weaver, Diorio, Seckl, Szyf, Meaney (2004): Early environmental regulation of hippocampal glucocorticoid receptor gene expression: characterization of intracellular mediators and potential genomic target sites. Ann N Y Acad Sci. 2004 Jun;1024:182-212. ↥

  6. Eckerle (2010?): Neurobiologische Forschungsergebnisse über den Zusammenhang zwischen Hochbegabung und psychischen Störungen (z.B. ADS) in der Adoleszenz ↥

  7. Nygaard, Slinning, Moe, Fjell, Walhovd (2019): Mental health in youth prenatally exposed to opioids and poly-drugs and raised in permanent foster/adoptive homes: A prospective longitudinal study. Early Hum Dev. 2019 Oct 29;140:104910. doi: 10.1016/j.earlhumdev.2019.104910. ↥

  8. Zeanah CH, Egger HL, Smyke AT, Nelson CA, Fox NA, Marshall PJ, Guthrie D (2009): Institutional rearing and psychiatric disorders in Romanian preschool children. Am J Psychiatry. 2009 Jul;166(7):777-85. doi: 10.1176/appi.ajp.2009.08091438. PMID: 19487394. ↥

  9. Humphreys KL, Zeanah CH (2014): Deviations from the expectable environment in early childhood and emerging psychopathology. Neuropsychopharmacology. 2015 Jan;40(1):154-70. doi: 10.1038/npp.2014.165. PMID: 24998622; PMCID: PMC4262894. REVIEW ↥ ↥

  10. Heneghan A, Stein RE, Hurlburt MS, Zhang J, Rolls-Reutz J, Fisher E, Landsverk J, Horwitz SM (2013): Mental health problems in teens investigated by U.S. child welfare agencies. J Adolesc Health. 2013 May;52(5):634-40. doi: 10.1016/j.jadohealth.2012.10.269. PMID: 23375826. ↥

  11. Greger HK, Kayed NS, Lehmann S, Jozefiak T, Lydersen S, Wichstrøm L, Fjukstad KK (2025): Prevalence and comorbidity of mental disorders among young adults with a history of residential youth care - a two-wave longitudinal study of stability and change. Eur Arch Psychiatry Clin Neurosci. 2025 Apr 27. doi: 10.1007/s00406-025-02007-x. PMID: 40287873. ↥

  12. Rutter M, Sonuga-Barke EJ, Castle J (2010): I. Investigating the impact of early institutional deprivation on development: background and research strategy of the English and Romanian Adoptees (ERA) study. Monogr Soc Res Child Dev. 2010 Apr;75(1):1-20. doi: 10.1111/j.1540-5834.2010.00548.x. PMID: 20500631. ↥

  13. Kennedy M, Kreppner J, Knights N, Kumsta R, Maughan B, Golm D, Rutter M, Schlotz W, Sonuga-Barke EJ (2016): Early severe institutional deprivation is associated with a persistent variant of adult attention-deficit/hyperactivity disorder: clinical presentation, developmental continuities and life circumstances in the English and Romanian Adoptees study. J Child Psychol Psychiatry. 2016 Oct;57(10):1113-25. doi: 10.1111/jcpp.12576. PMID: 27264475; PMCID: PMC5042050. ↥

  14. Gunnar MR, van Dulmen MH (2007): International Adoption Project Team. Behavior problems in postinstitutionalized internationally adopted children. Dev Psychopathol. 2007 Winter;19(1):129-48. doi: 10.1017/S0954579407070071. PMID: 17241487. ↥

  15. Kreppner JM, O’Connor TG, Rutter M (2001): English and Romanian Adoptees Study Team. Can inattention/overactivity be an institutional deprivation syndrome? J Abnorm Child Psychol. 2001 Dec;29(6):513-28. doi: 10.1023/a:1012229209190. PMID: 11761285. ↥

  16. Wiik KL, Loman MM, Van Ryzin MJ, Armstrong JM, Essex MJ, Pollak SD, Gunnar MR (2011): Behavioral and emotional symptoms of post-institutionalized children in middle childhood. J Child Psychol Psychiatry. 2011 Jan;52(1):56-63. doi: 10.1111/j.1469-7610.2010.02294.x. PMID: 20649913; PMCID: PMC2978793. ↥

  17. Saccaro, Schilliger, Perroud, Piguet (2021): Inflammation, Anxiety, and Stress in Attention-Deficit/Hyperactivity Disorder. Biomedicines. 2021 Sep 24;9(10):1313. doi: 10.3390/biomedicines9101313. PMID: 34680430; PMCID: PMC8533349. ↥ ↥

  18. Bali P, Sonuga-Barke E, Mohr-Jensen C, Demontis D, Minnis H. Is there evidence of a causal link between childhood maltreatment and attention deficit/hyperactivity disorder? A systematic review of prospective longitudinal studies using the Bradford-Hill criteria. JCPP Adv. 2023 May 27;3(4):e12169. doi: 10.1002/jcv2.12169. PMID: 38054051; PMCID: PMC10694545. METASTUDY ↥

  19. Jamil S, Raza ML, Moradikor N, Haghipanah M (2025): Early life stress and brain development: Neurobiological and behavioral effects of chronic stress. Prog Brain Res. 2025;291:49-79. doi: 10.1016/bs.pbr.2025.01.004. PMID: 40222792. REVIEW ↥

  20. Al Bazzal A, Mtairek MA, Awde MH, Kanso H, Hajj F, Al Amin F, Kazan Z, Mohammed NA, Hamdar H (2025): Stress-related psychiatric disorders. Prog Brain Res. 2025;291:161-173. doi: 10.1016/bs.pbr.2025.01.019. PMID: 40222778. REVIEW ↥

  21. Jangid R, Seema N, Arun G, Barre VP, Walia D, Rana S (2025): Interplay Between Adverse Childhood Experiences and Neurodevelopmental Disorders: A Systematic Review of Recent Evidence. Ann Neurosci. 2025 Jul 31:09727531251359413. doi: 10.1177/09727531251359413. PMID: 40756590; PMCID: PMC12313595. REVIEW ↥

  22. Merscher J, Retz W, Retz-Junginger P, Barra S (2026): Mediating roles of attention-deficit/hyperactivity disorder symptom severity and self-control on the relationship between adverse childhood experiences and adult aggression. J Neural Transm (Vienna). 2026 Mar;133(3):561-575. doi: 10.1007/s00702-025-03010-1. PMID: 40986036; PMCID: PMC12999651. ↥

  23. Karaçul FE, Arslan G (2026): Adverse Childhood Experiences and ADHD in College Students: Exploring the Role of Emotion Regulation and Self-Compassion. J Atten Disord. 2026 Feb;30(2):181-192. doi: 10.1177/10870547251370427. PMID: 40995879. ↥

  24. Davidsson M, Ringström F, Hagberg B, Gillberg C, Billstedt E (2025): Adverse childhood experiences in children with neurodevelopmental disorders and their parents. Nord J Psychiatry. 2025 Apr;79(3):185-193. doi: 10.1080/08039488.2025.2469737. PMID: 40008682. n = 171 ↥

  25. Alfonso D, Basurto K, Guilfoyle J, VanLandingham HB, Gonzalez C, Ovsiew GP, Rodriguez VJ, Resch ZJ, Ulrich DM, Soble JR (2023): The Effect of Adverse Childhood Experiences on ADHD Symptom Reporting, Psychological Symptoms, and Cognitive Performance Among Adult Neuropsychological Referrals. J Atten Disord. 2023 Sep 11:10870547231196326. doi: 10.1177/10870547231196326. PMID: 37694981. n = 115 ↥

  26. Husain, Allwood, Bell (2008): The relationship between PTSD symptoms and attention problems in children exposed to the Bosnian War. Journal of Emotional and Behavioral Disorders, 16: 52–62.; n = 791 ↥

  27. Daud, A. and Rydelius, P.-A. 2009. Comorbidity/overlapping between ADHD and PTSD in relation to IQ among children of traumatized/non-traumatized parents. Journal of Attention Disorders, 13: 188–98. ↥

  28. Famularo, Fenton, Kinscherff, Augustyn (1996): Psychiatric comorbidity in childhood post traumatic stress disorder. Child Abuse & Neglect, 20: 953–61 ↥

  29. Ford, Rascusin, Daviss, Fleisher, Thomas (2000): Child maltreatment, other trauma exposure, and posttraumatic symptomatology among children with oppositional defiant and attention deficit hyperactivity disorders. Child Maltreatment, 5: 205–17. ↥

  30. Lipschitz, Morgan, Southwick (2002): Neurobiological disturbances in youth with childhood trauma and in youth with conduct disorder. Journal of Aggression, Maltreatment & Trauma, 6: 149–74. ↥

  31. Sugarman (2006): Attention deficit hyperactivity disorder and trauma1. The International Journal of Psychoanalysis, 87: 237–241. doi:10.1516/F2BD-QXEU-NENX-QL3N ↥

  32. Dietrich (2010): Aufmerksamkeitsdefizit-Syndrom, Schattauer, Seite 51 ↥

  33. Rucklidge, Brown, Crawford, Kaplan (2006): Retrospective Reports of Childhood Trauma in Adults With ADHD. Journal of Attention Disorders, 9(4), 631–641. https://doi.org/10.1177/1087054705283892 ↥

  34. Biederman J, Milberger S, Faraone SV, Kiely K, Guite J, Mick E, Ablon JS, Warburton R, Reed E, Davis SG (1995): Impact of adversity on functioning and comorbidity in children with attention-deficit hyperactivity disorder. J Am Acad Child Adolesc Psychiatry. 1995 Nov;34(11):1495-503. doi: 10.1097/00004583-199511000-00017. PMID: 8543518. ↥

  35. Sugaya L, Hasin DS, Olfson M, Lin KH, Grant BF, Blanco C (2012): Child physical abuse and adult mental health: a national study. J Trauma Stress. 2012 Aug;25(4):384-92. doi: 10.1002/jts.21719. Epub 2012 Jul 16. PMID: 22806701; PMCID: PMC3805363. ↥

  36. Cuffe, McCullough, Pumariega (1994): Comorbidity of attention deficit hyperactivity disorder and post-traumatic stress disorder. Journal of Child and Family Studies, 3: 327–36. ↥

  37. Lee K, Fung HW (2024): The mediated model of PTSD between ADHD symptoms and alcohol abuse in a population of college students in Taiwan. J Formos Med Assoc. 2024 Aug 28:S0929-6646(24)00359-0. doi: 10.1016/j.jfma.2024.08.008. PMID: 39209668. ↥

  38. Boney-McCoy, Finkelhor (1995): Psychosocial sequel of violent victimization in a national youth sample. Journal of Consulting and Clinical Psychology, 63: 726–36. ↥ ↥

  39. Conway (2015): Attention Deficit Hyperactivity Disorder: Integration of Cognitive, Neuropsychological, and Psychodynamic Perspectives in Psychotherapy, am Ende des Kapitels “Das Eva-Projekt” ↥ ↥

  40. Bob P, Privara M (2025): ADHD, stress, and anxiety. Front Psychiatry. 2025 Mar 18;16:1536207. doi: 10.3389/fpsyt.2025.1536207. PMID: 40171307; PMCID: PMC11959059. REVIEW ↥ ↥

  41. Vuksanovic, Brisch (2010): ADHD, trauma and attachment – A new etiological model ↥

  42. Nilsen FM, Tulve NS. A systematic review and meta-analysis examining the interrelationships between chemical and non-chemical stressors and inherent characteristics in children with ADHD. Environ Res. 2020 Jan;180:108884. doi: 10.1016/j.envres.2019.108884. PMID: 31706600; PMCID: PMC6937727. METASTUDIE, k = 47 Studien ↥

  43. Davidsson M, Ringström F, Hagberg B, Gillberg C, Billstedt E (2025): Adverse childhood experiences in children with neurodevelopmental disorders and their parents. Nord J Psychiatry. 2025 Apr;79(3):185-193. doi: 10.1080/08039488.2025.2469737. PMID: 40008682. ↥

  44. Lazzaro G, Didino D, Fucà E, Sperandini V, Falvo S, Passarini S, Bergonzini P, D’Aiello B, De Rossi P, De Rose P, Vicari S, Menghini D (2025): Clinical phenotypes occurring after adverse childhood events: Differences and similarities with attention deficit and hyperactivity/impulsivity disorder. Child Abuse Negl. 2025 Sep;167:107561. doi: 10.1016/j.chiabu.2025.107561. PMID: 40517738. n = 122 ↥

  45. Hong SJ, Vu MH, Vanderbilt D, Yin L, Imagawa KK, Deavenport-Saman A (2025): The Coexistence of Adverse Childhood Experiences, Positive Childhood Experiences, and Parent-reported Attention-deficit/Hyperactivity Disorder Severity: National Survey of Children’s Health. J Dev Behav Pediatr. 2025 Sep-Oct 01;46(5):e468-e474. doi: 10.1097/DBP.0000000000001395. PMID: 40633056; PMCID: PMC12404043. n = 19.715 ↥

  46. Bock J, Breuer S, Poeggel G, Braun K (2017): Early life stress induces attention-deficit hyperactivity disorder (ADHD)-like behavioral and brain metabolic dysfunctions: functional imaging of methylphenidate treatment in a novel rodent model. Brain Struct Funct. 2017 Mar;222(2):765-780. doi: 10.1007/s00429-016-1244-7. PMID: 27306789; PMCID: PMC5334429. ↥

  47. Rüfenacht, Pham, Nicastro, Dieben, Hasler, Weibel, Perroud (2021): Link between History of Childhood Maltreatment and Emotion Dysregulation in Adults Suffering from Attention Deficit/Hyperactivity Disorder or Borderline Personality Disorder. Biomedicines. 2021 Oct 14;9(10):1469. doi: 10.3390/biomedicines9101469. PMID: 34680586; PMCID: PMC8533068. ↥ ↥

  48. Capusan, Kuja-Halkola, Bendtsen, Viding, McCrory, Marteinsdottir, Larsson (2016): Childhood maltreatment and attention deficit hyperactivity disorder symptoms in adults: a large twin study. Psychol Med. 2016 Sep;46(12):2637-46. doi: 10.1017/S0033291716001021. PMID: 27376862. n = 18.168 ↥

  49. González, Vélez-Pastrana, McCrory, Kallis, Aguila, Canino, Bird (2019): Evidence of concurrent and prospective associations between early maltreatment and ADHD through childhood and adolescence. Soc Psychiatry Psychiatr Epidemiol. 2019 Jun;54(6):671-682. doi: 10.1007/s00127-019-01659-0. PMID: 30903235. n = 2.480 ↥

  50. Rucklidge, Brown, Crawford, Kaplan (2006): Retrospective reports of childhood trauma in adults with ADHD. J Atten Disord. 2006 May;9(4):631-41. doi: 10.1177/1087054705283892. PMID: 16648230. ↥

  51. Sanderud, Murphy, Elklit (2016): Child maltreatment and ADHD symptoms in a sample of young adults. Eur J Psychotraumatol. 2016 Jun 14;7:32061. doi: 10.3402/ejpt.v7.32061. PMID: 27306866; PMCID: PMC4910305. n = 4.718 ↥

  52. Becker-Blease, Freyd (2006): A Preliminary Study of ADHD Symptoms and Correlates: Do Abused Children Differ from Nonabused Children? Journal of Aggression, Maltreatment & Trauma, Volume 17, 2008 – Issue 1, 133-140 ↥

  53. Stern, Agnew-Blais, Danese, Fisher, Jaffee, Matthews, Polanczyk, Arseneault (2018): Associations between abuse/neglect and ADHD from childhood to young adulthood: A prospective nationally-representative twin study. Child Abuse Negl. 2018 Jul;81:274-285. doi: 10.1016/j.chiabu.2018.04.025. PMID: 29775871; PMCID: PMC6013278. n = 2.232 ↥

  54. Briscoe-Smith, Hinshaw (2006): Linkages between child abuse and attention-deficit/hyperactivity disorder in girls: behavioral and social correlates. Child Abuse Negl. 2006 Nov;30(11):1239-55. doi: 10.1016/j.chiabu.2006.04.008. PMID: 17097140; PMCID: PMC1934403. ↥

  55. Gokten, Duman, Soylu, Uzun (2016): Effects of attention-deficit/hyperactivity disorder on child abuse and neglect. Child Abuse Negl. 2016 Dec;62:1-9. doi: 10.1016/j.chiabu.2016.10.007. PMID: 27770673. ↥

  56. Zou, Yu, Liang, Ma, Li, Bian, Zhang (2019): The Association Between Child Abuse and Emotional and Behavioral Problems in Chinese School-Aged Boys With Attention Deficit Hyperactivity Disorder. J Nerv Ment Dis. 2019 Jul 10. doi: 10.1097/NMD.0000000000001041. ↥

  57. Matthies, Sadohara-Bannwarth, Lehnhart, Schulte-Maeter, Philipsen (2018): The Impact of Depressive Symptoms and Traumatic Experiences on Quality of Life in Adults With ADHD. J Atten Disord. 2018 Mar;22(5):486-496. doi: 10.1177/1087054716654568. n = 120 ↥

  58. Retz-Junginger, Arweiler, Retz (2015: Trauma-Erfahrungen und sexueller Missbrauch bei ADHS; Zeitschrift für Psychiatrie, Psychologie und Psychotherapie (2015), 63, pp. 47-52. https://doi.org/10.1024/1661-4747/a000219. https://doi.org/10.1024/1661-4747/a000219; n = 125 Betroffene vs 195 Nichtbetroffene ↥

  59. Vrijsen JN, Tendolkar I, Onnink M, Hoogman M, Schene AH, Fernández G, van Oostrom I, Franke B (2018): ADHD symptoms in healthy adults are associated with stressful life events and negative memory bias. Atten Defic Hyperact Disord. 2018 Jun;10(2):151-160. doi: 10.1007/s12402-017-0241-x. PMID: 29081022; PMCID: PMC5973996. ↥

  60. Singer MJ, Humphreys KL, Lee SS (2016): Coping Self-Efficacy Mediates the Association Between Child Abuse and ADHD in Adulthood. J Atten Disord. 2016 Aug;20(8):695-703. doi: 10.1177/1087054712465337. PMID: 23204062. ↥

  61. Schiff SJ, Meza J, Bath E, Lee SS (2024): Commercially Sexually Exploited Adolescent Girls: The Association Between Externalizing Disorders and Parental Incarceration with Suicide Attempts. Child Psychiatry Hum Dev. 2024 Jun 27. doi: 10.1007/s10578-024-01730-1. PMID: 38935209. ↥

  62. Wimberley T, Brikell I, Pedersen EM, Agerbo E, Vilhjálmsson BJ, Albiñana C, Privé F, Thapar A, Langley K, Riglin L, Simonsen M, Nielsen HS, Børglum AD, Nordentoft M, Mortensen PB, Dalsgaard S (2022): Early-Life Injuries and the Development of Attention-Deficit/Hyperactivity Disorder. J Clin Psychiatry. 2022 Jan 4;83(1):21m14033. doi: 10.4088/JCP.21m14033. PMID: 34985833; PMCID: PMC7612325. ↥

  63. Vuksanovic (2013): Die Aktivität der Hypothalamus-Hypophysen-Nebennierenrinden-Achse bei Aufmerksamkeits-Defizit und Hyperaktivitäts-Störung, Dissertation, Seite 80 ff ↥ ↥

  64. Zehle (2007): Einfluss früher postnataler Stresserfahrung auf die Entwicklung des limbischen Systems bei Octodon degus: Verhaltenspharmakologische und neuroanatomische Untersuchungen zur Beteiligung des dopaminergen Systems ↥

  65. Annette Zoch: Vernarbte Seelen, Süddeutsche Zeitung, 29.09.2015, Seite 5 ↥

  66. Rucklidge, Brown, Crawford, Kaplan (2006): Retrospective Reports of Childhood Trauma in Adults With ADHD, Journal of Attention Disorders, Vol 9, Issue 4, 2006 ↥

  67. Stickley, Koposov, Koyanagi, Oh, Ruchkin (2019): Attention-Deficit/Hyperactivity Disorder Symptoms and Community Violence Exposure in Russian Adolescents. J Interpers Violence. 2019 Jul 9:886260519861651. doi: 10.1177/0886260519861651. ↥

  68. Espinosa Dice AL, Garrison-Desany HM, Ratanatharathorn A, Tiemeier H, Davey Smith G, Denckla CA (2024): Investigating Gene-Environment Interplay Between Bereavement and Polygenic Risk for Attention-Deficit/Hyperactivity Disorder on Externalizing Behaviors During Adolescence. JAACAP Open. 2024 May 27;3(2):323-334. doi: 10.1016/j.jaacop.2024.04.006. PMID: 40520970; PMCID: PMC12166943. ↥

  69. Hanć, Gomula, Nowak-Szczepanska, Chakraborty, Kozieł (2022): Prenatal and early postnatal exposure to a natural disaster and Attention-Deficit/Hyperactivity Disorder symptoms in Indian children. Sci Rep. 2022 Sep 28;12(1):16235. doi: 10.1038/s41598-022-20609-6. PMID: 36171270. ↥

  70. Hanson JL (2025): Stress About Eviction or Loss of Housing and Child Mental Health. JAMA Netw Open. 2025 Feb 3;8(2):e2458984. doi: 10.1001/jamanetworkopen.2024.58984. PMID: 39937477; PMCID: PMC11822551. n = 36.638 ↥

  71. Glynn LM, Liu SR, Golden C, Weiss M, Lucas CT, Cooper DM, Ehwerhemuepha L, Stern HS, Baram TZ (2025): Contribution of an under-recognized adversity to child health risk: large-scale, population-based ACEs screening. medRxiv [Preprint]. 2025 Feb 5:2025.02.04.25321682. doi: 10.1101/2025.02.04.25321682. PMID: 39974059; PMCID: PMC11838625. n = 29.305 ↥

  72. Ford, Racusin, Daviss, Ellis, Thomas, Rogers, Reiser, Schiffman, Sengupta (1999): Trauma exposure among children with oppositional defiant disorder and attention deficit–hyperactivity disorder. Journal of Consulting and Clinical Psychology, 67(5), 786-789. http://dx.doi.org/10.1037/0022-006X.67.5.786, n = 165 ↥

  73. Humphreys KL, Watts EL, Dennis EL, King LS, Thompson PM, Gotlib IH (2019): Stressful Life Events, ADHD Symptoms, and Brain Structure in Early Adolescence. J Abnorm Child Psychol. 2019 Mar;47(3):421-432. doi: 10.1007/s10802-018-0443-5. PMID: 29785533; PMCID: PMC6249129. ↥

  74. Schwartz A, Galera C, Kerbage H, Montagni I, Tzourio C (2023): Adverse Childhood Experiences and ADHD Symptoms Among French College Students. J Child Adolesc Trauma. 2023 Apr 10;16(4):1109-1117. doi: 10.1007/s40653-023-00543-z. PMID: 38045835; PMCID: PMC10689313. ↥

  75. Boswell E, Crouch E, Odahowski C, Hung P (2025): Examining the Association Between Adverse Childhood Experiences and ADHD in School-Aged Children Following the COVID-19 Pandemic. J Atten Disord. 2025 Jan;29(1):42-52. doi: 10.1177/10870547241290673. PMID: 39422221; PMCID: PMC11585178. n = 10.518 ↥

  76. Jimenez ME, Wade R Jr, Schwartz-Soicher O, Lin Y, Reichman NE (2017): Adverse Childhood Experiences and ADHD Diagnosis at Age 9 Years in a National Urban Sample. Acad Pediatr. 2017 May-Jun;17(4):356-361. doi: 10.1016/j.acap.2016.12.009. PMID: 28003143; PMCID: PMC5555409. n = 1.572 ↥

  77. Lyons K, Suh B (2025): Impact of adverse childhood experiences (ACEs) and positive childhood experiences (PCEs) on mental health among children aged 6-17 (2021-2022). J Affect Disord. 2025 Dec 15;391:120070. doi: 10.1016/j.jad.2025.120070. PMID: 40835185. ↥ ↥

  78. Brown NM, Brown SN, Briggs RD, Germán M, Belamarich PF, Oyeku SO (2017): Associations Between Adverse Childhood Experiences and ADHD Diagnosis and Severity. Acad Pediatr. 2017 May-Jun;17(4):349-355. doi: 10.1016/j.acap.2016.08.013. PMID: 28477799. n = 76.227 ↥

  79. Rodriguez VJ, Basurto KS, Finley JA, Liu Q, Khalid E, Halliburton AM, Tse PKY, Resch ZJ, Soble JR, Ulrich DM (2025): Multidimensional ADHD Symptom Profiles: Associations with Adverse Childhood Experiences. Arch Clin Neuropsychol. 2025 Jan 21;40(1):42-51. doi: 10.1093/arclin/acae050. PMID: 38916192. ↥

  80. Barra S, Machalica PK, Retz-Junginger P, Merscher J, Crombach A, Retz W (2025): Attention deficit/hyperactivity disorder (ADHD) dimensions mediate the relationship between adverse childhood experiences and adult aggression depending on cognitive reappraisal. Sci Rep. 2025 Jan 30;15(1):3806. doi: 10.1038/s41598-025-87861-4. PMID: 39885270; PMCID: PMC11782491. n = 287 ↥

  81. Grossman A, Avital A (2023):. Emotional and sensory dysregulation as a possible missing link in attention deficit hyperactivity disorder: A review. Front Behav Neurosci. 2023 Mar 2;17:1118937. doi: 10.3389/fnbeh.2023.1118937. PMID: 36935890; PMCID: PMC10017514. REVIEW ↥

  82. Sibley MH, Ortiz M, Graziano P, Dick A, Estrada E (2020): Metacognitive and motivation deficits, exposure to trauma, and high parental demands characterize adolescents with late-onset ADHD. Eur Child Adolesc Psychiatry. 2020 Apr;29(4):537-548. doi: 10.1007/s00787-019-01382-w. PMID: 31388765. ↥

  83. Yu C, Jiang W, Zhao D (2025): Association between adverse home environments and symptoms in drug-naive children with attention-deficit/hyperactivity disorder. Gen Psychiatr. 2025 Aug 14;38(4):e102078. doi: 10.1136/gpsych-2025-102078. PMID: 40822498; PMCID: PMC12352133. n = 343 ↥

  84. Friedrichs, Igl, Larsson, Larsson (2012): Coexisting psychiatric problems and stressful life events in adults with symptoms of ADHD–a large Swedish population-based study of twins. J Atten Disord. 2012 Jan;16(1):13-22. doi: 10.1177/1087054710376909. PMID: 20686099. n = 17.899 ↥

  85. Biederman, Milberger, Faraone, Kiely, Guite, Mick, Ablon, Warburton, Reed: Family-environment risk factors for attention deficit hyperactivity disorder: a test of Rutter’s indicators of adversity. Arch Gen Psychiatry 1995; 52: 464–70 (n= 260). Zitiert nach Philipsen, Heßlinger, Tebartz van Elst: AufmerksamkeitsdefizitHyperaktivitätsstörung im Erwachsenenalter – Diagnostik, Ätiologie und Therapie (ÜBERSICHTSARBEIT), Deutsches Ärzteblatt, Jg. 105, Heft 17, 25. April 2008, Seite 311 – 317, 313, Seite 314 ↥

  86. Brisch (2004): Der Einfluss von traumatischen Erfahrungen auf die Neurobiologie und die Entstehung von Bindungsstörungen. Psychotraumatologie und Medizinische Psychologie 2, 29-44, Link auf Beitrag gleichen Namens auf Webseite Brisch, mit anderer Seitennummerierung ↥

  87. Brisch (2004): Der Einfluss von traumatischen Erfahrungen auf die Neurobiologie und die Entstehung von Bindungsstörungen. Psychotraumatologie und Medizinische Psychologie 2, 29-44, Link auf Beitrag gleichen Namens auf Webseite Brisch, mit anderer Seitennummerierung, Link-Seite 25 ↥

  88. Glod, Teicher (1996): Relationship between early abuse, posttraumatic stress disorder, and activity levels in prepubertal children. J Am Acad Child Adolesc Psychiatry. 1996 Oct;35(10):1384-93. doi: 10.1097/00004583-199610000-00026. PMID: 8885593. ↥

  89. Kudielka, Schommer, Hellhammer, Kirschbaum (2004): Acute HPA axis responses, heart rate, and mood changes to psychosocial stress (TSST) in humans at different times of day. Psychoneuroendocrinology. 2004 Sep;29(8):983-92. doi: 10.1016/j.psyneuen.2003.08.009. PMID: 15219648. ↥

  90. Boney-McCoy, S. and Finkelhor, D.1995. Psychosocial sequel of violent victimization in a national youth sample. Journal of Consulting and Clinical Psychology, 63: 726–36. ↥

  91. Szymanski, Sapanski, Conway (2011): Trauma and ADHD – Association or Diagnostic Confusion? A Clinical Perspective; Journal of Infant, Child, and Adolescent Psychotherapy Vol. 10, Iss. 1, 2011 ↥

  92. Çoban, Tan (2019): Attention Deficit Hyperactivity Disorder, Impulsivity, Anxiety, and Depression Symptoms Mediating the Relationship Between Childhood Trauma and Symptoms Severity of Obsessive-Compulsive Disorder. Noro Psikiyatr Ars. 2019 Aug 16;57(1):37-43. doi: 10.29399/npa.23654. PMID: 32110149; PMCID: PMC7024829. ↥

  93. Lexikon der Biologie: Genotyp-Umwelt-Interaktion. Spektrum.de Abruf 12.10.2019. ↥

  94. Amano, Toichi (2016): The Role of Alternating Bilateral Stimulation in Establishing Positive Cognition in EMDR Therapy: A Multi-Channel Near-Infrared Spectroscopy Study. PLoS One. 2016 Oct 12;11(10):e0162735. doi: 10.1371/journal.pone.0162735. eCollection 2016 ↥

  95. Hellström (2019): A Systematic Review of Polyvictimization among Children with Attention Deficit Hyperactivity or Autism Spectrum Disorder. Int J Environ Res Public Health. 2019 Jun 27;16(13). pii: E2280. doi: 10.3390/ijerph16132280. ↥

  96. Knight AR, Kim S, Currao A, Lebas A, Nowak MK, Milberg WP, Fortier CB (2025): Assessing Attention-Deficit/Hyperactivity Disorder in Post-9/11 Veterans: Prevalence, Measurement Correspondence, and Comorbidity With Posttraumatic Stress Disorder. Mil Med. 2025 Apr 23;190(5-6):e1106-e1113. doi: 10.1093/milmed/usae539. PMID: 39607449; PMCID: PMC12016034. ↥ ↥

  97. Hartman, Rommelse, van der Klugt, Wanders, Timmerman (2019): Stress Exposure and the Course of ADHD from Childhood to Young Adulthood: Comorbid Severe Emotion Dysregulation or Mood and Anxiety Problems. J Clin Med. 2019 Nov 1;8(11). pii: E1824. doi: 10.3390/jcm8111824. n = 609 ↥

  98. Pani, Porcella, Gessa (2000): The role of stress in the pathophysiology of the dopaminergic system. Mol Psychiatry. 2000 Jan;5(1):14-21. doi: 10.1038/sj.mp.4000589. PMID: 10673764. REVIEW ↥ ↥

  99. Hall, Wilkinson, Humby, Robbins (1999): Maternal deprivation of neonatal rats produces enduring changes in dopamine function. Synapse. 1999 Apr;32(1):37-43. doi: 10.1002/(SICI)1098-2396(199904)32:1<37::AID-SYN5>3.0.CO;2-4. PMID: 10188636. ↥

  100. Burke, Renner, Forster, Watt (2010): Adolescent social defeat alters neural, endocrine and behavioral responses to amphetamine in adult male rats. Brain Res. 2010 Sep 17;1352:147-56. doi: 10.1016/j.brainres.2010.06.062. PMID: 20603109; PMCID: PMC2926242. ↥

  101. Choy, de Visser, van den Buuse (2009): The effect of ‘two hit’ neonatal and young-adult stress on dopaminergic modulation of prepulse inhibition and dopamine receptor density. Br J Pharmacol. 2009 Jan;156(2):388-96. doi: 10.1111/j.1476-5381.2008.00008.x. PMID: 19154431; PMCID: PMC2697842. ↥

  102. Walker, Diforio (1997): Schizophrenia: a neural diathesis-stress model. Psychol Rev. 1997 Oct;104(4):667-85. doi: 10.1037/0033-295x.104.4.667. PMID: 9337628. ↥

  103. Latagliata, Valzania, Pascucci, Campus, Cabib, Puglisi-Allegra (2014): Stress-induced activation of ventral tegmental mu-opioid receptors reduces accumbens dopamine tone by enhancing dopamine transmission in the medial pre-frontal cortex. Psychopharmacology (Berl). 2014 Oct;231(21):4099-108. doi: 10.1007/s00213-014-3549-7. PMID: 24958228. ↥ ↥

  104. Abercrombie, Keefe, DiFrischia, Zigmond (1989): Differential effect of stress on in vivo dopamine release in striatum, nucleus accumbens, and medial frontal cortex. J Neurochem. 1989 May;52(5):1655-8. doi: 10.1111/j.1471-4159.1989.tb09224.x. PMID: 2709017. ↥ ↥ ↥

  105. Sudha, Pradhan (1995): Stress-induced changes in regional monoamine metabolism and behavior in rats. Physiol Behav. 1995 Jun;57(6):1061-6. doi: 10.1016/0031-9384(94)00369-g. PMID: 7544468. ↥ ↥ ↥

  106. Keefe, Stricker, Zigmond, Abercrombie (1990): Environmental stress increases extracellular dopamine in striatum of 6-hydroxydopamine-treated rats: in vivo microdialysis studies. Brain Res. 1990 Sep 17;527(2):350-3. doi: 10.1016/0006-8993(90)91158-d. PMID: 2123730. ↥

  107. Ventura, Coccurello, Andolina, Latagliata, Zanettini, Lampis, Battaglia, D’Amato, Moles (2013): Postnatal aversive experience impairs sensitivity to natural rewards and increases susceptibility to negative events in adult life. Cereb Cortex. 2013 Jul;23(7):1606-17. doi: 10.1093/cercor/bhs145. PMID: 22669969. ↥ ↥

  108. Watt, Roberts, Scholl, Meyer, Miiller, Barr, Novick, Renner, Forster (2014): Decreased prefrontal cortex dopamine activity following adolescent social defeat in male rats: role of dopamine D2 receptors. Psychopharmacology (Berl). 2014 Apr;231(8):1627-36. doi: 10.1007/s00213-013-3353-9. PMID: 24271009; PMCID: PMC3969403. ↥

  109. Boksa, El-Khodor (2003):. Birth insult interacts with stress at adulthood to alter dopaminergic function in animal models: possible implications for schizophrenia and other disorders. Neurosci Biobehav Rev. 2003 Jan-Mar;27(1-2):91-101. doi: 10.1016/s0149-7634(03)00012-5. PMID: 12732226. REVIEW ↥

  110. Pruessner, Champagne, Meaney, Dagher (2004): Dopamine release in response to a psychological stress in humans and its relationship to early life maternal care: a positron emission tomography study using [11C]raclopride. J Neurosci. 2004 Mar 17;24(11):2825-31. doi: 10.1523/JNEUROSCI.3422-03.2004. PMID: 15028776; PMCID: PMC6729514. ↥

  111. Soliman, O’Driscoll, Pruessner, Holahan, Boileau, Gagnon, Dagher (2007): Stress-induced dopamine release in humans at risk of psychosis: a [11C]raclopride PET study. Neuropsychopharmacology. 2008 Jul;33(8):2033-41. doi: 10.1038/sj.npp.1301597. PMID: 17957215. ↥

  112. Nagano-Saito, Dagher, Booij, Gravel, Welfeld, Casey, Leyton, Benkelfat (2013): Stress-induced dopamine release in human medial prefrontal cortex–18F-fallypride/PET study in healthy volunteers. Synapse. 2013 Dec;67(12):821-30. doi: 10.1002/syn.21700. PMID: 23939822. ↥

  113. Mizrahi, Addington, Rusjan, Suridjan, Ng, Boileau, Pruessner, Remington, Houle, Wilson (2012): Increased stress-induced dopamine release in psychosis. Biol Psychiatry. 2012 Mar 15;71(6):561-7. doi: 10.1016/j.biopsych.2011.10.009. PMID: 22133268. ↥

  114. Scornaiencki, Cantrup, Rushlow, Rajakumar (2009): Prefrontal cortical D1 dopamine receptors modulate subcortical D2 dopamine receptor-mediated stress responsiveness. Int J Neuropsychopharmacol. 2009 Oct;12(9):1195-208. doi: 10.1017/S1461145709000121. PMID: 19275776. ↥

  115. Oswald, Wand, Kuwabara, Wong, Zhu, Brasic (2014): History of childhood adversity is positively associated with ventral striatal dopamine responses to amphetamine. Psychopharmacology (Berl). 2014 Jun;231(12):2417-33. doi: 10.1007/s00213-013-3407-z. PMID: 24448898; PMCID: PMC4040334. ↥ ↥

  116. Lee, Coccaro (2010): Plasma homovanillic acid correlates inversely with history of childhood trauma in personality disordered and healthy control adults. J Neural Transm (Vienna). 2010 Nov;117(11):1327-34. doi: 10.1007/s00702-010-0493-5. PMID: 20953642. ↥

  117. Higley, Suomi (1992): Linnoila M. A longitudinal assessment of CSF monoamine metabolite and plasma cortisol concentrations in young rhesus monkeys. Biol Psychiatry. 1992 Jul 15;32(2):127-45. doi: 10.1016/0006-3223(92)90016-s. PMID: 1384725. ↥

  118. Kasanova, Hernaus, Vaessen, van Amelsvoort, Winz, Heinzel, Pruessner, Mottaghy, Collip, Myin-Germeys (2016): Early-Life Stress Affects Stress-Related Prefrontal Dopamine Activity in Healthy Adults, but Not in Individuals with Psychotic Disorder. PLoS One. 2016 Mar 23;11(3):e0150746. doi: 10.1371/journal.pone.0150746. PMID: 27007554; PMCID: PMC4805207. ↥

  119. Read J, van Os J, Morrison AP, Ross CA (2005): Childhood trauma, psychosis and schizophrenia: a literature review with theoretical and clinical implications. Acta Psychiatr Scand. 2005 Nov;112(5):330-50. doi: 10.1111/j.1600-0447.2005.00634.x. PMID: 16223421. REVIEW ↥

  120. Varese F, Smeets F, Drukker M, Lieverse R, Lataster T, Viechtbauer W, Read J, van Os J, Bentall RP (2012): Childhood adversities increase the risk of psychosis: a meta-analysis of patient-control, prospective- and cross-sectional cohort studies. Schizophr Bull. 2012 Jun;38(4):661-71. doi: 10.1093/schbul/sbs050. PMID: 22461484; PMCID: PMC3406538. REVIEW ↥

  121. Gul MK, Cagir B, Demirci E, Ozmen S (2025): The relationship between response to treatment and perceived stress, childhood trauma and psychological resilience in anxiety disorders and attention-deficit hyperactivity disorder in adolescents: A comparative study from Türkiye. Arch Psychiatr Nurs. 2025 Apr;55:151856. doi: 10.1016/j.apnu.2025.151856. PMID: 40204375. ↥

  122. Xing Tan, Wang, Hao, Li (2021): Female adopted Chinese-American youth’s sense of exclusion and short-and long-term adjustment. Am J Orthopsychiatry. 2021 Jun 24. doi: 10.1037/ort0000568. PMID: 34166054. n = 224 ↥

  123. Layton, Barnett, Hicks, Jena (2018): Attention Deficit–Hyperactivity Disorder and Month of School Enrollment; N Engl J Med 2018; 379:2122-2130, DOI: 10.1056/NEJMoa1806828 ↥

  124. Caye, Petresco, de Barros, Bressan, Gadelha, Gonçalves, Manfro, Matijasevich, Menezes, Miguel, Munhoz, Pan, Salum, Santos, Kieling, Rohde (2019): Relative Age and Attention-Deficit/Hyperactivity Disorder: Data From Three Epidemiological Cohorts and a Meta-Analysis. J Am Acad Child Adolesc Psychiatry. 2019 Jul 31. pii: S0890-8567(19)31432-7. doi: 10.1016/j.jaac.2019.07.939. ↥

  125. Root, Brown, Forbes, Bhaskaran, Hayes, Smeeth, Douglas (2019): Association of Relative Age in the School Year With Diagnosis of Intellectual Disability, Attention-Deficit/Hyperactivity Disorder, and Depression. JAMA Pediatr. 2019 Sep 23. doi: 10.1001/jamapediatrics.2019.3194. ↥

  126. Ponnou S, Thomé B (2022): ADHD diagnosis and methylphenidate consumption in children and adolescents: A systematic analysis of health databases in France over the period 2010-2019. Front Psychiatry. 2022 Oct 10;13:957242. doi: 10.3389/fpsyt.2022.957242. PMID: 36299551; PMCID: PMC9590284. ↥

  127. Dee, Sievertsen (2018): The gift of time? School starting age and mental health. Health Econ. 2018 May;27(5):781-802. doi: 10.1002/hec.3638. PMID: 29424005. n = 8.092 ↥

  128. Whitely M, Raven M, Timimi S, Jureidini J, Phillimore J, Leo J, Moncrieff J, Landman P. Attention deficit hyperactivity disorder late birthdate effect common in both high and low prescribing international jurisdictions: a systematic review. J Child Psychol Psychiatry. 2019 Apr;60(4):380-391. doi: 10.1111/jcpp.12991. Epub 2018 Oct 14. PMID: 30317644; PMCID: PMC7379308. ↥

  129. Dalsgaard, Humlum, Nielsen, Simonsen (2014): Common Danish standards in prescribing medication for children and adolescents with ADHD. Eur Child Adolesc Psychiatry. 2014 Sep;23(9):841-4. doi: 10.1007/s00787-013-0508-5. PMID: 24374648. ↥

  130. Helsen, van Winckel, Williams (2005) The relative age effect in youth soccer across Europe. J Sports Sci. 2005 Jun;23(6):629-36. ↥

  131. Elder (2010): The importance of relative standards in ADHD diagnoses: evidence based on exact birth dates. J Health Econ. 2010 Sep;29(5):641-56. doi: 10.1016/j.jhealeco.2010.06.003. PMID: 20638739; PMCID: PMC2933294. ↥

  132. Balestra, Eugster, Liebert (2020): Summer-born struggle: The effect of school starting age on health, education, and work. Health Econ. 2020 Feb 12. doi: 10.1002/hec.4005. PMID: 32052533. ↥

  133. Synergy for the Influence of the Month of Birth in ADHD (SIMBA) study group (2023): Association between relative age at school and persistence of ADHD in prospective studies: an individual participant data meta-analysis. Lancet Psychiatry. 2023 Oct 25:S2215-0366(23)00272-9. doi: 10.1016/S2215-0366(23)00272-9. PMID: 37898142. METASTUDY ↥

  134. Deng Q, Coleman JRI, Mottershead E, Ronald A, Zavos HMS, Kuntsi J (2024): Relative Age Effects on Attention-Deficit/Hyperactivity Disorder Symptoms and Educational Achievement: A Longitudinal UK Cohort Study. JAACAP Open. 2024 Feb 5;2(3):199-207. doi: 10.1016/j.jaacop.2024.01.004. PMID: 39552820; PMCID: PMC11562434. n = 8.508 ↥

  135. Glassgow, Gerges, Atkins, Martin, Caskey, Sanders, Mirza, Van Voorhees, Kim (2019): Exploring Racial Disparities in Mental Health Diagnoses and Neighborhood Disorganization Among an Urban Cohort of Children and Adolescents with Chronic Medical Conditions. Health Equity. 2019 Nov 22;3(1):604-611. doi: 10.1089/heq.2019.0085. eCollection 2019. ↥

  136. Nfonoyim, Griffis, Guevara (2020): Disparities in Childhood Attention Deficit Hyperactivity Disorder Symptom Severity by Neighborhood Poverty. Acad Pediatr. 2020 Sep-Oct;20(7):917-925. doi: 10.1016/j.acap.2020.02.015. PMID: 32081765. ↥

  137. Kim Y, Kim SH, Kim J, Lee J, Hong SB (2025): Regional educational environment and its association with attention-deficit/hyperactivity disorder diagnosis in South Korea (2013-2019). Soc Psychiatry Psychiatr Epidemiol. 2025 Feb 18. doi: 10.1007/s00127-025-02847-x. PMID: 39966162. ↥

  138. Havey JM, Olson JM, McCormick C, Cates GL (2005): Teachers’ perceptions of the incidence and management of attention-deficit hyperactivity disorder. Appl Neuropsychol. 2005;12(2):120-7. doi: 10.1207/s15324826an1202_7. PMID: 16083400. ↥

  139. Purper-Ouakil D, Wohl M, Michel G, Mouren MC, Gorwood P (2004): Variations dans l’expression clinique du trouble déficit attentionnel/hyperactivité (TDAH): rôle du contexte, du développement et de la comorbidité thymique [Symptom variations in ADHD: importance of context, development and comorbidity]. Encephale. 2004 Nov-Dec;30(6):533-9. French. doi: 10.1016/s0013-7006(04)95467-x. PMID: 15738855. REVIEW ↥

  140. Demange PA, Boomsma DI, van Bergen E, Nivard MG (2023): Evaluating the causal relationship between educational attainment and mental health. medRxiv [Preprint]. 2023 Jan 26:2023.01.26.23285029. doi: 10.1101/2023.01.26.23285029. PMID: 36747639; PMCID: PMC9901051. n = 1,7 Mio. ↥

  141. Christakis, Zimmerman, DiGiuseppe, McCarty (2004): Early television exposure and subsequent attentional problems in children. Pediatrics. 2004 Apr;113(4):708-13. n = 2.623 ↥

  142. Wu JB, Yang Y, Zhou Q, Li J, Yang WK, Yin X, Qiu SY, Zhang J, Meng M, Guo Y, Chen JH, Chen Z (2025): The relationship between screen time, screen content for children aged 1-3, and the risk of ADHD in preschools. PLoS One. 2025 Apr 23;20(4):e0312654. doi: 10.1371/journal.pone.0312654. PMID: 40267918; PMCID: PMC12017831. n = 41.494 ↥

  143. Hill MM, Gangi DN, Miller M (2024): Toddler Screen Time: Longitudinal Associations with Autism and ADHD Symptoms and Developmental Outcomes. Child Psychiatry Hum Dev. 2024 Nov 29. doi: 10.1007/s10578-024-01785-0. PMID: 39609334. ↥

  144. Murray A, Casey H, Wright H, Zhu X, Yang Y, Li X, Xiao Z, King J, Kostyrka-Allchorne K, Sonuga-Barke E (2025): The effects of tv/video viewing hours on later ADHD symptoms: a counterfactual analysis in longitudinal population-representative data. BMC Pediatr. 2025 Sep 1;25(1):673. doi: 10.1186/s12887-025-05973-2. PMID: 40890658; PMCID: PMC12400586. ↥

  145. Augner C, Vlasak T, Barth A (2023): The relationship between problematic internet use and attention deficit, hyperactivity and impulsivity: A meta-analysis. J Psychiatr Res. 2023 Oct 16;168:1-12. doi: 10.1016/j.jpsychires.2023.10.032. PMID: 37866293. ↥

  146. Zivan, Bar, Jing, Hutton, Farah, Horowitz-Kraus (2019): Screen-exposure and altered brain activation related to attention in preschool children: An EEG study. Trends Neurosci Educ. 2019 Dec;17:100117. doi: 10.1016/j.tine.2019.100117. ↥

  147. Güzel Y, Öztürk M (2025): The effect of digital parental awareness and somatic symptoms on problematic media use in children with attention-deficit/hyperactivity disorder. J Pediatr Nurs. 2025 Jan-Feb;80:e236-e245. doi: 10.1016/j.pedn.2024.12.019. PMID: 39741077. n = 185 ↥

  148. Meng Z, Ao B, Wang W, Niu T, Chen Y, Ma X, Huang Y (2024): Relationships between screen time and childhood attention deficit hyperactivity disorder: a Mendelian randomization study. Front Psychiatry. 2024 Sep 23;15:1441191. doi: 10.3389/fpsyt.2024.1441191. PMID: 39376970; PMCID: PMC11457377. ↥

  149. Elvin ÖD, Aydan ÇV, Güzel EÇ, Topçu B (2024): Evaluation of the relationship between the frequency of attention deficit, hyperactivity disorder symptoms and nutritional habits in children. Med J Malaysia. 2024 Sep;79(5):538-546. PMID: 39352155. ↥

  150. Harlé (2019): Intensive early screen exposure as a causal factor for symptoms of autistic spectrum disorder: The case for «Virtual autism». Trends Neurosci Educ. 2019 Dec;17:100119. doi: 10.1016/j.tine.2019.100119. ↥

  151. Hussein RA, Refai RH, El-Zoka AH, Azouz HG, Hussein MF (2025): Association between some environmental risk factors and attention-deficit hyperactivity disorder among children in Egypt: a case-control study. Ital J Pediatr. 2025 Jan 29;51(1):19. doi: 10.1186/s13052-025-01843-w. PMID: 39875928; PMCID: PMC11776284. n = 252 ↥

  152. Takahashi N, Tsuchiya KJ, Okumura A, Harada T, Iwabuchi T, Rahman MS, Kuwabara H, Nomura Y, Nishimura T (2023): The association between screen time and genetic risks for neurodevelopmental disorders in children. Psychiatry Res. 2023 Sep;327:115395. doi: 10.1016/j.psychres.2023.115395. PMID: 37574599. n = 437 ↥

  153. Cai C, Ran Q, Lu M, Song C, Jiang Z (2025): Leisure Screen Time and the Risk of Six Neurodevelopmental Disorders: A Two-Sample Mendelian Randomization Study. Brain Behav. 2025 Sep;15(9):e70884. doi: 10.1002/brb3.70884. PMID: 40977001; PMCID: PMC12451015. ↥

  154. Boer, Stevens, Finkenauer, van den Eijnden (2019): Attention Deficit Hyperactivity Disorder-Symptoms, Social Media Use Intensity, and Social Media Use Problems in Adolescents: Investigating Directionality. Child Dev. 2019 Oct 26. doi: 10.1111/cdev.13334. ↥

  155. Deng H, Song K, Geng X, Xu L, Zhang J, Li X, He J, Potenza MN, Zhang J (2024): Online social activity time predicts ADHD problems in youth from late childhood to early adolescence in the ABCD study. Eur Child Adolesc Psychiatry. 2024 Dec 26. doi: 10.1007/s00787-024-02620-6. PMID: 39724179. ↥

  156. Özbek MM, Sevinçok D, Mısır E (2025): The Relationship Between Familial Functioning and Social Media Use Among Children with Depression and Attention Deficit Hyperactivity Disorder: A Comparative Study with Healthy Controls. Children (Basel). 2025 Jul 9;12(7):906. doi: 10.3390/children12070906. PMID: 40723100; PMCID: PMC12294095. ↥

  157. Martínez Del Río C, Cuellar-Flores I, López de Lara D, Castañeda-Vozmediano R, Miguélez González M, Gaitero Pérez A, Pérez Rodríguez O, García Ron A (2025): Attention deficit hyperactivity disorder risk, mental health diagnoses and experience of discrimination in transgender adolescents and youth. Endocrinol Diabetes Nutr (Engl Ed). 2025 Oct;72(8):501593. doi: 10.1016/j.endien.2025.501593. PMID: 40946028. ↥

  158. Yulug-Tas B, Ozbaran B, Inal-Kaleli I, Dogan N, Jalilova A, Ozen S, Kose S, Goksen D, Darcan S, Bildik T (2025): Social Cognition in Adolescents With Gender Dysphoria and Congenital Adrenal Hyperplasia: A Preliminary Investigation of Biological vs. Experiential Gender Effects. J Clin Res Pediatr Endocrinol. 2025 Sep 25. doi: 10.4274/jcrpe.galenos.2025.2025-3-16. PMID: 40996024. ↥

  159. Köder F, Sharma C, Cameron S, Garraffa M (2022):The effects of bilingualism on cognition and behaviour in individuals with attention deficits: A scoping review. Front Psychol. 2022 Dec 23;13:1057501. doi: 10.3389/fpsyg.2022.1057501. PMID: 36619112; PMCID: PMC9816333. METASTUDIE ↥

  160. Hansen, Qureshi, Gele, Hauge, Biele, Surén, Kjøllesdal (2023): Developmental disorders among Norwegian-born children with immigrant parents. Child Adolesc Psychiatry Ment Health. 2023 Jan 6;17(1):3. doi: 10.1186/s13034-022-00547-x. PMID: 36609392; PMCID: PMC9825022. ↥

  161. Chang J, Lee YJ, Lex H, Kerns C, Lugar K, Wright M (2023): Attention-Deficit Hyperactivity Disorder among children of immigrants: immigrant generation and family poverty. Ethn Health. 2023 Dec 17:1-13. doi: 10.1080/13557858.2023.2293657. PMID: 38105627. n = 83.362 ↥

  162. Crouch E, Radcliff E, Boswell E, Brown MJ, Hung P (2024): Association Between Positive Childhood Experiences and Caregiver-Reported ADHD Diagnosis and Severity. J Dev Behav Pediatr. 2024 Nov-Dec 01;45(6):e531-e536. doi: 10.1097/DBP.0000000000001315. PMID: 39377729. ↥