4. Attention and concentration problems with ADHD

Author: Ulrich Brennecke
Review: Dipl.-Psych. Waldemar Zdero

Attention problems in ADHD have various manifestations, such as attention lapses, shortened attention span, task switching problems, difficulty listening and following instructions, and difficulty completing tasks. There are three groups of attention problems in ADHD: distractibility, attention switching problems (task switching problems) and concentration problems.
Distractibility can be caused by external stimuli or internal thoughts. Daydreaming / mind wandering is a form of distractibility in which attention drifts off without external stimuli.
Task switching problems describe difficulties in directing attention to another task when this is necessary. Hyperfocus is a state of intense concentration on topics that are of personal interest to the person with ADHD and is a subset of task switching problems.
Attention is the allocation of conscious resources to content. Concentration, on the other hand, is the measure of the intensity and duration of attention.

Attention in ADHD is not “defective” overall. Rather, it is subject to a deviating activation profile, which would be helpful in the case of severe, life-threatening stress, but is very detrimental outside of this.
Attention problems in ADHD arise from a lack of attention regulation.¹ As attention is essentially motivation-driven (attention follows interest), the attention problems in ADHD, which mainly occur during activities that are subjectively perceived as less interesting, are largely a consequence of the motivational deficits triggered by the dopamine deficiency in the brain’s reinforcement system.
While the realization that attention problems in ADHD are primarily a motivational problem has become widely accepted, it is often still unknown that this also applies to motor restlessness. A Time-lapse video, which shows a person with ADHD watching a video that is intrinsically interesting and one that is intrinsically uninterestingillustrates that hyperactivity problems are also caused by motivational factors.

ADHD is usually associated with attention and concentration problems. However, there is the ADHD-HI presentation (formerly: subtype), in which attention problems are less pronounced or may even be completely absent and hyperactivity and impulsivity predominate. ADHD-HI occurs mainly in children and is often regarded as a precursor to ADHD-C, in which attention problems are added to hyperactivity. Nevertheless, we know quite a few adult people with ADHD without severe attention problems, but with pronounced other ADHD symptoms. The possibility of ADHD without attention problems should also be considered in adults.

The age development of attention problems shows that inattention is not present from the beginning and declines less in adulthood than hyperactivity and impulsivity. It is controversial whether attention problems can diminish in adulthood while hyperactivity/impulsivity and other symptoms persist. If ADHD no longer exists in adulthood, inattention also remits. In principle, it is therefore possible for attention problems to disappear. However, statistical data suggests that attention problems remit less frequently than hyperactivity.

Problems with sustaining attention for longer periods of time during tasks or leisure activities is one of the 9 most accurate symptoms of ADHD in adults.²

Attention problems can also be a symptom of stress and occur in many mental disorders. Attention problems are the second most common symptom of all disorders in the DSM 5.³ Stress reduces the ability to control attention. A reduced ability to concentrate can also occur outside of ADHD.

• 4.1. Forms of attention
• 4.2. Manifestations of attention problems with ADHD
• 4.3. Groups of attention problems with ADHD
  • 4.3.1. Distractibility
    • 4.3.1.1. Distractibility due to external stimuli
    • 4.3.1.2. Mental unrest
    • 4.3.1.2.1. Daydreaming / mind wandering / absent-mindedness
    • 4.3.1.2.2. Racing thoughts
  • 4.3.2. Attention switching problems
    • 4.3.2.1. Task switching problems / set shifting problems
    • 4.3.2.2. Hyperfocus: extreme concentration
  • 4.3.3. Concentration problems as ADHD symptoms
• 4.4. Cause of attention problems in ADHD - motivational problems?
• 4.5. Age development of attention problems in ADHD
• 4.6. ADHD without attention and concentration problems
• 4.7. Attention problems as symptoms of stress

4.1. Forms of attention¶

There are various forms of attention, e.g:

• selective attention
• sustained attention
• focused attention
• changing attention
• covert attention
  • hidden voluntary (endogenous) attention
  • concealed involuntary (exogenous) attention
  • Both increase contrast sensitivity, improve spatial resolution, accelerate the absorption of information and even change the appearance of stimuli⁴

The different forms of attention have different neurological bases¹
People with ADHD appear to have deficits in all forms of attention except for fully functional covert attention.⁴

4.2. Manifestations of attention problems with ADHD¶

• Careless mistakes
  • For children:
    • Often misses details or makes careless mistakes in schoolwork, work or other activities (DSM IV, DSM 5)
  • For adults:
    • Aversion to instructions⁵
    • Lack of concentration when reading through longer tasks⁵
    • Overwhelm longer instructions
• Attention span shortened or impaired
  • For children:
    • Often has difficulty sustaining attention on a task/game for long periods of time (DSM IV/5)
    • Often avoids / has an aversion to / is often reluctant to engage in tasks that require prolonged mental effort (DSM IV / 5)
  • For adults:
    • Boring tasks increase distractibility⁵
• Task switching problems
  • For children:
    • Does not seem to listen when others speak to him/her (DSM IV / 5)
    • Still thinking somewhere else
  • For adults
    • Speed of switching between tasks (task switching) reduced⁶
    • Are still busy with their own thoughts from the previous task⁵
    • Can no longer get out of thought loops
• Listening is difficult
  • Attention span is too short to follow instructions to the end
    (Tendency to interrupt, on the other hand, is an impulsivity problem)
• Implementation of instructions is difficult
  • Adults: Overload due to lack of ability to organize tasks⁵
  • When structuring tasks, attention is already drawn to the details
• Tasks are often not completed
  • Children:
    • Often does not fully follow instructions from others and is unable to complete schoolwork, other work or duties at work (DSM IV / 5)
  • Adults:
    • In the middle of a task, the focus changes to something else
      • Cleaning example⁷
        • The floor is mopped, right up to the table
        • There the focus shifts to clearing it out
        • When you go into another room to put something away, you find the open closet and the clothes in front of it and start to put them away.
        • You only remember to mop the floor when you come into the living room and are surprised to find the bucket and the mob at the table..
      • While working, you search for something on the Internet and magically get trapped there..
• Concentration problems
  • Attention cannot be sustained for long periods and is not intense enough to maintain concentration for a long time
  • Tasks with short and frequently changing requirements are preferred
  • Tasks that require prolonged concentration and effort are unpleasant and are often avoided

4.3. Groups of attention problems with ADHD¶

We divide attention problems in ADHD into 3 groups:

• Distractibility: increased change of focus of attention; problems keeping attention on an object when necessary
• Attention switching problems: problems disengaging attention from an object when required
• Concentration problems: problems focusing attention on one object for a longer period of time or permanently when required, even without distraction

These three groups represent different forms of attention problems, all of which are typical of ADHD. All three groups occur more frequently in people with ADHD than in those without the disorder.

4.3.1. Distractibility¶

Depending on the cause, distractibility can be divided into

• In relation to external, external stimuli
  • Distractibility
    • Is often distracted by external stimuli (DSM IV / V)
    • Not being able to overhear conversations at the next table
    • Can’t look away when a TV is on in a pub
• Through internal secondary thoughts (mind wandering, daydreaming, drifting away, autopilot)
  • To be distinguished from the phenomenon of dissociation, which represents a separation of thinking, feeling, perception and action

Distractibility is one of the 9 most accurate symptoms of ADHD in adults.⁸
A larger study (n = 1,289) meta-analysis found that distractibility in adults with ADHD is predominantly due to mind wandering rather than external stimuli.⁹

4.3.1.1. Distractibility due to external stimuli¶

Distractibility is a fluctuation in attention due to external stimuli. People with ADHD show increased distractibility more often than people without ADHD
This form of distractibility by external stimuli initially appears to be a direct consequence of the stimulus filter being too wide open (increased sensitivity). Against the background of the deviating regime of attention control, however, it is questionable whether the stimulus filter disorder is the main cause. On the one hand, it is primarily the degree of personal interest or the resulting motivation that determines whether attention is directed or distractible. Furthermore, not only the distractibility but also the directionality is temporarily increased (task switching problems) while at the same time the basic mechanisms of attention and its control are technically functioning. In our view, this could indicate that the attention problems in ADHD are Consequences of a change in motivational control rather than genuine deficits in attention itself or merely the result of reduced perceptual filtering.

Although people with ADHD are distracted by unimportant stimuli from the environment, their selective attention is barely impaired.¹⁰ The latter is only partially covered by the results of our symptom test. Task switching problems (problems with switching / selecting attention) occur less frequently with ADHD than distractibility, but are just as rare in people without ADHD, so that the difference in frequency of distractibility and task switching problems between people with ADHD and those without ADHD is roughly identical.

Children with ADHD showed¹¹

• visual distraction stimuli a stronger decrease in sustained attention and inhibitory control (impulse control).
• auditory distraction stimuli showed unchanged performance, while controls showed an increase in performance.

4.3.1.2. Mental unrest¶

4.3.1.2.1. Daydreaming / mind wandering / absent-mindedness¶

Daydreaming is not a form of distraction by external stimuli. Rather, attention wanders without an external stimulus. Mind wandering or absent-mindedness are equivalent terms. Mind wandering encompasses a range of mental phenomena that involve a shift of attention from a task to “incoherent inner thoughts, fantasies, feelings and other musings”.¹²

Daydreaming can be measured with the Mind Wandering Questionnaire (MWQ).

A distinction is made between spontaneous mind wandering and deliberate mind wandering.
More pronounced ADHD symptoms are associated with more frequent spontaneous (uncontrolled) mind wandering and less intentional (directed) mind wandering than with weaker ADHD symptoms.¹³¹⁴¹⁵ Mind wandering is a core symptom of ADHD.⁹

255 adult people with ADHD were differentiated into hi-level mind wanderers and low-level mind wanderers according to the MWQ score of more or less than 24. Daydreaming is therefore not specifically associated with the ADHD-I subtype without hyperactivity (“dreamer”), but correlates significantly with¹⁶

• Higher inattention
• Higher hyperactivity
• Poorer executive functions
• More general mental health problems
• Higher emotional dysregulation
• More severely impaired quality of life

i.e. with increased ADHD symptoms in general.

Increased mind wandering (daydreaming) was also found in children with ADHD. Daydreaming could detect ADHD in a group of people with ADHD and non-affected people with a sensitivity of 0.71 and a specificity of 0.81.¹⁷

An interesting report mentions partial brain sleep as a possible cause of some SCT symptoms or daydreaming.¹⁸

One study found daydreaming in adults to be a symptom independent of ADHD that correlated with anxiety but not depression.¹⁹

A study using event-related EEG measurements during tasks with high and low demands on working memory and sustained attention as well as during phases of mind wandering and task focus found in people with ADHD:²⁰

• weaker decrease in alpha power
  • with high demands on the working memory
  • with requirements for sustained attention
• weaker increase in theta power and weaker phase consistency
  • with demands on the working memory
  • with low demands on sustained attention
• weaker decrease in beta power
  • with low demands on the working memory
• weaker decrease in alpha power during mind-wandering episodes
  • in the task of sustained attention
• lower consistency of theta phase during mind wandering episodes
  • in the task of working memory

Mind wandering correlated with general impairment and emotional dysregulation, but not with risk-taking behavior and homework problems.²¹

4.3.1.2.2. Racing thoughts¶

Racing thoughts comprise three types of thinking:²²

• Thought overactivation (an excessive amount and speed of thoughts)
• Burden of thought overactivation (an overwhelming effect of thought overactivation)
• Thought hyperexcitability (the distractibility caused by racing thoughts)

Subjective descriptions of racing thoughts are (in the case of a manic Disorder in its strong manifestation):²³

• a subjective acceleration and overproduction of thoughts
• Flight of ideas
• a torrent of almost unstoppable speech; thoughts leap from topic to topic, held only by a thin thread of recognizable associations. Ideas fly out, and as they do, they rhyme, make puns and coalesce in inimitable ways. The spirit is alive, electric.²⁴
• Flight of thought
• subjective experience of racing thoughts
• Thoughts can race, often faster than they can be articulated
• This experience is similar to watching two or three television programs at the same time
• Thought logorrhea, with abrupt changes of subject, so that speech can be disorganized and incoherent

A study distinguishing mental restlessness into racing and crowded thoughts and mind wandering. Mental restlessness is mainly explained by excessive wandering of thoughts. The three facets of racing thoughts correlated with emotional instability. Intentional as well as spontaneous mind wandering and daydreaming did not correlate with ADHD symptoms or functional impairment. The authors concluded that racing thoughts and mind wandering are different phenomena and that racing thoughts could possibly explain the mental restlessness in adults with ADHD.²⁵
A previous study by the authors’ group found that racing thoughts were more strongly associated with ADHD than with hypomania or euthymia and correlated with cyclothymic features and anxiety. In ADHD, racing thoughts increased in the evening and before bedtime and correlated with the severity of insomnia.²⁶

4.3.2. Attention switching problems¶

4.3.2.1. Task switching problems / set shifting problems¶

Task switching problems (problems with set-shifting / task switching) describe a difficulty in turning attention to another object in response to an external demand, i.e. to stop an activity or occupation that is currently being carried out in response to an extrinsic demand in order to devote oneself to the new demand. Consequences are the difficulty in stopping an activity or behavior when one should.

Task switching or set-shifting is described in psychology as the ability to unconsciously shift attention from one task to another. Task switching, on the other hand, describes the conscious change from one task or requirement to another.

Task switching problems are an ADHD symptom.²⁷ It is difficult for people with ADHD to disengage their attention from things that interest them personally enough to motivate them²⁸ - especially if the request to switch tasks is extrinsic and the subject of the new request does not address the personal interest of the person with ADHD.
Task switching problems are therefore a consequence of the altered attention control regime, which in turn is controlled by the motivational state.

Task switching problems are one of the 9 most accurate symptoms of ADHD in adults.⁸

Manifestations of task switching problems in ADHD:

• Problems spontaneously putting down something that is currently preoccupying them and turning their attention to something else
• Difficulties changing the task after an external request
• Difficulties in focusing attention on a new external topic
• Advance notice is preferred for a new activity
  • 10/15 minutes advance notice can help
• Difficulty getting previous activity out of your head
• Difficulties in completing the occupation with a thought/topic/problem
• New external demands while you are still preoccupied with something else internally can easily trigger stress / impulsive reactions

One person with ADHD asked his employees, when they came to his office, to enter without knocking, but then not to speak to him, but simply to take a seat on a chair next to the door, look out of the window and wait until he could finish what he was doing
This way of behaving (which was certainly impolite without such an agreement) prevented him from having to react immediately and saved him from having to snort deeply and annoyed when employees came in and wanted something from him, even though he was still busy with something else
The symptoms of the task switching problems were clearly maintained even under stimulant medication.

4.3.2.2. Hyperfocus: extreme concentration¶

Hyperfocus is a very strong ability to concentrate when performing activities involving things that are of great personal interest to the person with ADHD. This is often accompanied by a reduced ability to perceive distracting stimuli.

Hyperfocus is a well-known symptom of ADHD that also occurs in autism and schizophrenia.²⁹ Hyperfocus correlates strongly with ADHD.³⁰
Hyperfocus is not really a problem unless there is a severe lack of perception of external stimuli in this state. It is certainly an advantage to be able to concentrate particularly intensely on certain things. Nevertheless, it is a specific feature of ADHD, which is why it is a symptom. In addition, people with ADHD are unable to control their hyperfocus.

People with ADHD can show very good attention and concentration (up to hyperfocus) when there is personal interest,³¹ once they have started an activity that gives them satisfaction, because the reward that is then immediately received keeps the reinforcement center active. Anyone who has ever experienced a person with ADHD in hyperfocus, in which even highly monotonous activities can be carried out with great concentration for hours, provided that the personal interest of the person with ADHD is aroused, and in which the external stimuli irrelevant to the current interest are very well blocked out, can confirm this from their own experience.
However, this interest is much more difficult to achieve due to the lower number of dopamine D2 and D3 receptors in the striatum.³²
Against this background, it could be assumed that in ADHD it is not the ability to pay attention and concentrate that is impaired, but the control of attention. However, in our opinion, this description also falls somewhat short. We believe that the mechanisms of attention control are not impaired in ADHD, but that the control of attention control is impaired. Compared to a car, neither the driving itself (the attention) nor the steering mechanism (where it goes) is impaired, but the driver is the problem - he steers the (fully functioning) car (the attention) towards an inappropriate destination. (The driver here is not the person with ADHD, but a symbol for the impaired instance of attentional control of the person with ADHD). The orientation of attention is subject to an inappropriate regime: that of an existence-threatening stress situation. In such a situation, the attention typical of ADHD would be helpful (stress benefit). More on this below.

The so-called hyperfocus - another term is “flow”²⁹ - is a state in which people with ADHD (contrary to the typical symptoms) can focus on a topic persistently, concentrated and free from frustration intolerance or distractibility.

When it comes to topics that particularly fascinate the person with ADHD, they can easily spend hours, days and nights on a very specific topic³⁴ and have a very steep learning curve (just like people without ADHD). In contrast, the learning curve for ADHD is typically slower or delayed for less interesting topics.³⁵

Many people with ADHD are very familiar with the state of hyperfocus when they are really interested in something. In this state, they are able to focus on a topic for a long time without being burdened by concentration problems, attention problems, distractibility or frustration intolerance. The problem is that the required interest is not sufficiently controllable.

All people can concentrate better on things that interest them. However, people without ADHD are much better at motivating themselves to concentrate on less exciting things than people with ADHD.³⁶ This is not a question of character or effort, but simply a question of ability.³⁷ To the extent that people with ADHD lack this ability, it is a symptom of ADHD. Brown, the director of the Yale Clinic for Attention and Related Disorders in New Haven, Connecticut, quotes a person with ADHD with the beautiful image of mental erectile dysfunction. If something is interesting enough to motivate you, you can act. If there is no personal interest, you can do whatever you want - it won’t work.³⁶

We do not share Barkley’s interpretation that³⁸ hyperfocus is a form of perseveration,³⁹ i.e. a form of concomitant disorder. A disorder always requires subjective suffering on the part of the people with ADHD. Barely any person with ADHD perceives hyperfocus as a burden. At most, the associated limited ability to change tasks is described as stressful, but this must be distinguished from the hyperfocus itself.
Moreover, we are reluctant to call something that enables us to concentrate for hours on end if the topic is exciting enough a “concomitant disorder”. Rather, hyperfocus is a healthy reaction to intense interest. We interpret the increased occurrence of hyperfocus in people with ADHD as an indication that the intensity of interest in people with ADHD differs from that of non-affected people. It can be significantly lower (resulting in attention problems) or significantly higher (resulting in task switching problems or hyperfocus).

4.3.3. Concentration problems as ADHD symptoms¶

Concentration is the purposeful focus of attention on a specific object over a longer period of time, in contrast to distractibility in the case of attention problems.
Concentration problems can result from an attention span that is too short. This short attention span seems to exist independently of distractibility problems.

Concentration problems are a major symptom of ADHD. Problems with sustaining attention during tasks or leisure activities is one of the 9 most accurate symptoms of ADHD in adults.⁸ According to another opinion, concentration problems are less common in ADHD compared to attention problems.⁴⁰

Consequences of a shortened attention span can be that people with ADHD avoid or have an aversion to engaging in tasks that require prolonged mental effort. A short attention span also increases the difficulty of following instructions to the end.

4.4. Cause of attention problems in ADHD - motivational problems?¶

The basic (technical) functionality of attention and attention control is not impaired in ADHD. Attention problems in ADHD are the result of attention and motivation control following other motives. The regime, the standards by which attention is directed, is altered. It corresponds to that of people who are subject to extreme, life-threatening stressors and is “technically” healthy insofar as such a reaction pattern is helpful for survival in the event of an existential threat. Altered attention can be seen as a healthy response to severe stressors, just as fever is a healthy immune response to pathogens. The disorder in ADHD lies in the fact that this attention regime is used even though there are no adequate stressors. In this picture, a fever reaction without an existing pathogen or trigger would be comparable.

Children with ADHD often show normal attention skills when doing things they like (intrinsic motivation), but have difficulties with externally imposed demands that do not arouse their interest (extrinsic motivation).⁴¹ Control is increasingly subject to personal motives. It is not the basic ability to pay attention that is impaired, but the ability to control it (to direct it towards something as well as away from something).⁴²

This pattern is reminiscent of “kinesia paradoxa” in Parkinson’s disease. Parkinson’s sufferers with severe movement restrictions, due to which they can barely move - let alone walk - can suddenly be able to move fluently and even run away from dangerous areas, for example, in situations of severe danger (which by their very nature generate high intrinsic motivation).⁴³⁴⁴

ADHD fluctuates between temporarily reduced distractibility (task switching problems or, more rarely, so-called hyperfocus) and temporarily increased distractibility. When which deviation occurs depends crucially on whether there is sufficient personal interest in the activity or occupation being carried out. People with ADHD require higher incentives in order to feel the same level of motivation as people without ADHD. If intrinsic interests or extrinsic incentives such as rewards are high enough to trigger motivation, the attention and inhibition performance of people with ADHD is sometimes indistinguishable from that of non-affected people.

The model of intrinsic and extrinsic motivation roughly correlates with the distinction between automatic (passive) attention and directed attention. Automatic attention is triggered in particular by novel stimuli (unknown or unexpected in a particular environment) and signal stimuli (usually emotional: familiar and even expectable, but critical stimuli for the individual, such as food, mating partners or danger). The automatic attention mechanisms are unconscious and stimulus-driven (bottom-up)⁴⁵ and appear to be located in the brain region of the ACC⁴⁶
Directed attention is controlled top-down⁴⁶ and is associated with concentration and effort in difficult or uninteresting tasks (e.g. tax return, cleaning the bathroom, boring homework). Directed attention is mediated by executive functions⁴⁷, which are not automatically retrieved but cognitively coordinated. Executive functions are impaired in ADHD.

Inattention can - especially in adults - be masked by anxiety or compulsive coping strategies.⁴⁸

4.5. Age development of attention problems in ADHD¶

Attention problems do not appear in kindergarten or the first years of school.⁴⁹ Some sources even mention 14 or 15 years for the first manifestation.⁵⁰ A very early first manifestation of attention problems is described in fetal alcohol syndrome.⁵¹
Attention problems remit less frequently and less severely in adulthood than hyperactivity and impulsivity.⁵² We therefore consider the view that attention problems always remain high in adulthood⁴⁹ to be questionable in this dogmatic formulation.

4.6. ADHD without attention and concentration problems¶

Attention problems are one of the most noticeable ADHD symptoms after hyperactivity.
Nevertheless, these are not present in all people with ADHD. DSM IV, which (unlike the current DSM 5) still defined subtypes, used the ADHD-HI subtype to describe people with ADHD who predominantly had hyperactive-impulsive symptoms and barely any attention problems. This subtype without attention problems is primarily found in children and is likely to be a precursor to ADHD-C in many cases. Due to the development of the human brain, attention problems only become apparent from the age of 7,⁴⁹ according to some even from the age of 14 or 15,⁵⁰ unless as a symptom of other disorders, e.g. fetal alcohol syndrome.⁵¹
This has sometimes been interpreted to mean that the pure ADHD-HI subtype (only hyperactivity, no inattention) only occurs up to this age.⁵³ We rather suspect that although the pure ADHD-HI subtype is often a precursor to ADHD-C in children, there is still a significant proportion (just under 10%) of people with ADHD without severe attention problems but with significant other ADHD symptoms among adults.

Of 1433 participants in our ADxS.org symptom test (as of June 2020) with a positive ADHD test (screening) result (1390 of whom were 20 years or older), 102 (7.1%) were found to have no concentration/attention problems (1 of whom was younger than 20 years). 21 (1.5 %) showed no distractibility, 162 (11.3 %) no task switching problems.
Among non-ADHD sufferers, the proportion of people with ADHD affected by distractibility was significantly higher than for concentration problems or task switching problems, so that the diagnostic accuracy (the difference in the measures of concentration problems, distractibility and task switching problems) between ADHD sufferers and non-sufferers was approximately the same in each case.

It is controversial whether relevant problems with inattention, once they have occurred, can subside or remit in adulthood.⁵⁴⁵⁵ If ADHD does not necessarily persist for life, i.e. if 30% of all people with ADHD in childhood remit in adulthood at least to such an extent that a diagnosis can no longer be given, inattention does not necessarily remit at the same time. Statistical data confirm that inattention remits less frequently than hyperactivity and that the reduction in symptom severity is lower with inattention. Nevertheless, a remission of attention problems was found in 10 to 15% of 18-20-year-olds who still had ADHD.⁵² A study of 144 adults who had been diagnosed with ADHD as children found that 3.3% had a purely hyperactive form of ADHD, i.e. hyperactivity without attention problems.⁵⁶
It is possible that inattention is one of the symptoms that contributes to noticeable impairments for the longest time.

We know quite a few people with ADHD who show a wide range of typical ADHD symptoms and also respond positively to stimulants, but have little to no problems in the area of attention. People with ADHD who show several symptoms of an overreactive stress response system (i.e. overreacting inappropriately to the external situation) suffer from the remaining symptoms even if attention problems are not among them.

There is no doubt that there are (former) people with ADHD who have remitted the inattention and hyperactivity of their childhood and adolescence. This is because the symptoms persist into adulthood in only around 50% of all people with ADHD.
There are undisputedly people with ADHD who have no hyperactivity at all (ADHD-I).

The other way around:
Hyperactivity usually turns into Inner drivenness in adulthood. This is somewhat less unpleasantly noticeable, but no less stressful for the person with ADHD.
People who had pure ADHD-HI (without attention problems) as children and adolescents and whose hyperactivity has changed to pure inner restlessness typical of adults and thus no longer attract negative attention through hyperactivity, and who have always had no attention problems, may be more pleasant for those around them and are therefore probably more often not suspected of having a stressful Disorder. However, if the stress caused by the other symptoms persists, these people also have a right to help and treatment.

We therefore support the hypothesis that there is a (small) group of people with ADHD in whom attention problems are rather weak or have subsided completely. The test diagnostics used by some doctors and therapists, which are aimed solely at persistent attention deficits or which exclude ADHD without attention problems⁵⁷ are therefore misleading in this view and could fail to capture just under 10% of adults with ADHD.

According to this view, the decisive factor is not whether certain individual symptoms of the symptom cluster are present, but whether

• A large number of symptoms from the symptom totality occur
  and
• Whose occurrence independently (outside) of acute stress situations (e.g. bullying, family problems) justifies a diagnosis.

This corresponds to the model presented by Barkley ⁵⁸, according to which people with ADHD can be identified quite reliably from non-affected persons on the basis of the number of frequent occurrences of 18 symptoms. See the text in the introduction to this article.

As a rule, attention problems are a central symptom of ADHD. However, even though this tends to be the exception, the possibility of ADHD without attention problems should not be ignored, even in adults.
⇒ Neurophysiological correlates of attention problems in ADHD

4.7. Attention problems as symptoms of stress¶

Distractibility, attention problems and susceptibility to disruption are typical symptoms of severe stress.^59606162 Concentration disorders are a typical symptom of severe stress, even outside of ADHD.^6359646065

Almost every mental Disorder is associated with attention problems,⁶⁶ e.g.:

• Depression
• Psychosis
• Tourette’s
• Mania
• Panic disorders
• Obsessive-compulsive disorders

Stress reduces the voluntary ability to control attention (the “searchlight of attention”). In the extreme case of a shock, the ability to control attention is virtually eliminated.⁶⁷

A comprehensible overview of attention can be found at <http://www.neuropaedagogik.de/html/aufmerksamkeit.html>.