Stress benefits - the survival-enhancing purpose of stress
According to our hypothesis, ADHD mediates its symptoms by triggering a chronic overreactivity of the stress regulation systems, especially the HPA axis. The stress regulatory systems altered by ADHD respond with an (exaggerated) stress response even to life circumstances that are not stressful for unaffected individuals.
⇒ ADHD as a chronicized stress regulation disorder
Stress itself is not a disease. Stress is a healthy reaction of the organism to cope with increased demands (stressors). Stress causes physical, psychological and neurological changes. Stress thereby reinforces evolutionary selection as a result.1
Extreme, unmanageable, uncontrollable stress changes how we feel and think in order to achieve optimal problem solving. These specific changes are useful for coping with increased demands. This is what we call stress benefits.
The physical benefits of stress have long been recognized and acknowledged. The psychological stress benefits, on the other hand, have received little attention and are hardly discussed in the relevant literature on stress.
Quite a few stress benefits are mediated directly through the HPA axis.
Others are a result of a change in the PFC.
The shift of behavioral control from slow but accurate PFC to fast but inaccurate posterior and subcortical brain regions serves a rapid action capability in survival-threatening situations2 and is triggered during acute severe stress by means of very high levels of dopamine and norepinephrine and/or glucocorticoids.
In ADHD, there is also an impairment of the working memory located in the dorsolateral PFC - however, not as a consequence of high dopamine or norepinephrine levels due to severe acute stress, but in ADHD due to an underactivation of the PFC as a consequence of reduced dopamine levels. Decreased dopamine levels in the PFC may be caused by genetic constellations (as is usually the case in ADHD) or may be the result of chronic stress.3
The result, deactivation of the PFC and impairment of working memory, is identical for both too high and too low dopamine levels, because the brain’s neurons function optimally only at intermediate levels of dopamine and norepinephrine.
ADHD involves a multitude of gene polymorphisms inherited over thousands of years, which alter the expression of genes in such a way that (among other things) the dopamine level in the PFC and other brain regions is reduced. (Early childhood) stress may additionally damage the dopaminergic system and furthermore represent an epigenetic cause of the formation of certain gene expressions that also reduce dopamine levels. Epigenetic gene alterations are also heritable, although usually “only” over several generations, and can have the same effect on gene expression in offspring without the latter having to have suffered (early childhood) stress themselves.
Not all stress/ADHD symptoms have a direct stress benefit themselves. Some are merely nature’s accepted consequence of the stress benefit of another symptom that is so beneficial that the associated disadvantages are outweighed. Otherwise, for lack of sufficient stress benefit (or associated disadvantages, which shall be called stress benefit consequence here), this stress symptom would probably have gone extinct long ago.
- 1. Physical stress benefits
- 2. Neurological stress benefits
- 3. Mental stress benefits
4. Stress benefits of individual stress symptoms
- 4.1. Stress benefits of hyperactivity
- 4.2. Stress benefits of inhibition problems / impulse control problems
- 4.3. Stress benefits of distractibility, task switching problems, and attention problems
- 4.4. Stress benefits of procrastination aversion (e.g., impatience) and procrastination
- 4.5. Stress benefits of dysphoria during inactivity
- 4.6. Stress benefits of listlessness
- 4.7. Stress benefits of devaluing later rewards
- 4.8. Stress benefits of aversion to inactivity
- 4.9. Stress benefits of inability to enjoy
- 4.10. Stress benefits of high sensitivity
4.11. The stress benefits of inner turmoil
- 4.11.1. Stress benefits of being internally driven
- 4.11.2. The stress benefit of dealing with the stressor / thought circling / rumination
- 4.11.3. The stress benefits of “doing what you’re doing right now, mostly in a rush”
- 4.11.4. Stress utility of “difficulty in quietly pursuing a leisure activity”
- 4.12. Mood swings as stress benefit consequences
- 4.13. Frustration intolerance as a stress benefit consequence
- 4.14. Stress Benefits of Rejection Sensitivity
- 4.15. Stress benefits of Tend and Befriend
- 4.16. Stress benefits of self-esteem problems
- 4.17. Stress benefits of anxiety
- 4.18. Stress benefits of inner emptiness and alexithymia
- 4.19. Stress benefits of reduced/increased empathy
- 4.20. Stress benefits of Novelty Seeking
- 4.21. Stress benefits of increased risk taking
- 4.22. Stress benefits of communication problems
- 4.23. Organizational difficulties as a stress benefit consequence
- 4.24. Stress benefits of impaired performance
- 4.25. Stress benefits from feeling overwhelmed
- 4.26. Time estimation error as a stress benefit sequence
- 4.27. Stress benefits of sleep problems
- 5. Stress symptoms that are not typical ADHD symptoms
- 6. Individual variance in stress symptoms as a survival advantage for group and genus
- 7. Stress benefits explain difference ADHD / other mental disorders
1. Physical stress benefits
The physical changes increase the ability to fight and flee.
- Increased heart rate:
increased supply of oxygen-rich blood to the organs for increased physical performance
- Constriction of peripheral blood vessels (turning pale):
Blood is drawn to the inside of the body. Protection against bleeding in case of possible injuries due to fight or flight
- Increased activity of the liver:
more glucose in the blood, increased short-term energy availability
Inhibition of inflammation:
reduced energy expenditure for the immune system by suppressing its activity, which has advantages for the desired short-term optimization of the ability to act.
In the case of long-term stress, however, this weakening of the immune system has a detrimental effect and in extreme cases can even lead to death4
- Reduced sex drive; in extreme cases: infertility.
In life-threatening situations, pregnancy would be a significant additional burden.
This is also evolutionary from the perspective of the species: stress inhibits the reproduction of those individuals that are not optimally adapted to the environmental conditions4
- Muscle tension
Pre-tensioning the muscles protects against injury in the event of a possible fight or flight.
2. Neurological stress benefits
The brain is constantly changed by positive and negative experiences (neuroplasticity). Neuroplasticity does not end with adulthood, but it does decrease. Neuroplasticity is a basic prerequisite for learning.
Light / controllable stress reinforces existing neural connections, as they have proven their competence by successfully completing the task.5
Strong / uncontrollable stress, on the other hand, supports the dissolution of existing neural connections in the brain to make way for newer, better models, since the problem-solving models represented in the previous connections have proven to be less than optimal for avoiding the stressful situation that now exists (in extreme cases: threatening survival).
Many people know that certain of their habits are dysfunctional and still do not manage to change them. After a drastic experience (uncontrollable stress) they are suddenly able to change their habits.
Stressors that are too intense, too often, for too long damage the stress response systems. In the first years of life, while the neurotransmitter systems of the brain are forming and searching for an appropriate balance for the respective neurotransmitters, the stress response systems are particularly vulnerable to this. Certain genetic dispositions may further increase this vulnerability. ⇒ How does ADHD develop? Genes + environment
Neural plasticity is mediated by the adaptation of neurochemical, neuroanatomical, and behavioral systems. In this process, the endocrine system acts as a signaling network that triggers chemical and morphological changes in specific neurons and glial cells. The hippocampus (which controls learning and memory processes) responds to glucocorticoids during the diurnal cycle and in response to stress (cortisol binds to glucocorticoid receptors) as well as vasopressin, among others.
Cyclic AMP accumulation stimulated by norepinephrine, an index of decreased norepinephrine sensitivity due to prolonged stress, is increased by removal or blockade of the adrenal gland where cortisol and other stress hormones are produced, while cortisol or ACTH are reduced.6
Slightly elevated levels of glucocorticoids (cortisol) as a result of positive experiences (including successfully overcoming a challenge) promote the growth of neurons, whereas strongly elevated levels of glucocorticoids inhibit this.789
In contrast, intensive negative experiences, and these include in particular stressful situations that cannot be mastered, weaken the previous circuitry in the brain and support its degradation. Since the previous circuitry was obviously not sufficiently suitable to cope with the situation encountered, but allowed the individual to get into an unmanageable (potentially dangerous) situation, it makes sense to weaken it and stimulate the growth of new, better pathways and circuitry.7
3. Mental stress benefits
Stress causes very typical psychological symptoms. In our view, almost all ADHD symptoms are functional stress symptoms. (*⇒ ADHD symptoms are stress symptoms. These symptoms have had immediate benefits for the survival of the individual and thus its species for several million years.
Suppose one of our ancestors faced a potentially life-threatening situation. Be it a saber-toothed tiger that doesn’t look like it’s just sluggishly dragging itself into the shadows from a sumptuous meal, or a group of warriors from an unknown or even hostile tribe approaching at a run.
Now the poor guy already has enough problems on his hands - what use are stress symptoms to our ancestor? What advantage do they have?
Now, we no longer live in the savannah, we no longer have to hunt our food, and we have outsourced protection from predators or warriors to the police and the army. But our stress systems are millions of years old and have been very successful for a very long time. Accordingly, they are deeply anchored and it will take a correspondingly long time for them to give way to newer stress responses that are more adapted to modern life. Once we get into the picture of the ancient living conditions that have existed since the dawn of hominids, this leads to a profound understanding of the original benefits of stress symptoms.
Stress benefits are not the results of a cognitive deliberation that the person or the stress response system have done in advance in silence in order to implement them in that way when the time comes. We regard stress benefits as successful reaction patterns that have evolved in evolutionary biology. The sufferers with these response patterns are the descendants of those who had developed these patterns by chance and for whom these patterns successfully helped them survive. Therefore, they were more likely to be represented in subsequent generations than other behavioral and response patterns that were not as beneficial for survival.
Functional stress symptoms are reactions and behavior patterns that are helpful in extreme situations to increase the probability of survival.
The conclusion must then be that stress symptoms are first of all completely healthy neurophysiological reactions. ADHD symptoms, on the other hand, are not, although they are identical: because ADHD triggers these symptoms without an adequate stressor being present.
However, this explains why any attempt to understand the neurophysiological pathway of ADHD symptoms as a disease component must fail. For if the emergence of an ADHD symptom were to be interrupted at its neurophysiological path of emergence, this would at the same time also interrupt the healthy stress symptoms, which are a functional reaction to a stressor.
4. Stress benefits of individual stress symptoms
4.1. Stress benefits of hyperactivity
Increased physical activity and willingness to be active is helpful in fight or flight and promotes survival.
Hyperactivity occurs mainly in children and adolescents and subsides in adulthood. This could indicate a particular advantage in escape.
In addition to this stress benefit, hyperactivity acts as a stress reduction tool:
Hyperactivity can be observed in animals at the same time as an act of hyperactivity during uncontrollable stress (with increased cortisol blood levels), whereby these acts of hyperactivity at the same time measurably serve to reduce stress (reduction of stress levels).1011
In adults, hyperactivity is primarily perceptible as constantly repeating micro-movements: foot tapping, finger tapping, etc. These constantly repeated movements have a certain similarity to stereotypies or tics, which also have a stress-relieving effect as skip actions.1211
4.1.1. Fine motor problems as a stress benefit consequence
From the perspective of movement optimization, a deterioration of gross and fine motor skills is not plausible. Especially in combat situations, at least gross motor skills are important.
Under stress, reaction speed is increased. This is at the expense of the accuracy of motor actions. In this respect, the deterioration of fine motor skills is not a stress benefit, but a (detrimental) consequence of another stress benefit, namely the increase in reaction speed.
4.2. Stress benefits of inhibition problems / impulse control problems
Spontaneous, ill-considered decisions do not initially appear to be an expedient response to a stressor. The less time spent on decision-making, the greater the risk of wrong decisions.
Norepinephrine is the primary stress hormone of the central nervous system (the brain). A slightly increased norepinephrine level, as occurs during controllable stress, stimulates the PFC to increased activity. Only a very high level of norepinephrine, as occurs with uncontrollable stress, shuts down the PFC and activates the stress axis (HPA axis), at the end of which cortisol is released. To ensure that the deactivation of the PFC does not remain a permanent state, cortisol causes norepinephrine to be cut back again at the end.
In ADHD-HI, the stress systems are permanently overactivated because too low an endocrine stress response does not shut down the PFC and HPA axis. The particular high endocrine stress response could explain the subtype ADHD-I (and possibly SCT given the symptomatology) with too frequent shutdown of the PFC and HPA axis.
In contrast, under extreme stress - in fight or flight - it is sometimes simply necessary for survival to make decisions very quickly.We are the descendants of those who were at least not the slowest in hitting or running away. We have inherited from the winners (the survivors) their stress response that extreme stress turns off the PFC because faster responses are advantageous in fight or flight.
If you suddenly find yourself facing a hungry lion in the savannah, you should decide as quickly as possible in which direction to run. In the race to be at best the second slowest, the younger parts of the brain (especially the PFC), which are optimized for careful analytical consideration of problems but do so very very slowly, are rather a hindrance. Fast, spontaneous (but inaccurate) decisions have always been made by the older (and smaller) brain parts of the limbic system (amygdala, hippocampus).
However, this is probably not due to advantages in energy consumption. The energy consumption of the brain in the resting state as well as in the alarm state is approximately the same. Whether it is therefore a survival advantage to shut down the new brain parts, which are not very helpful in such emergency situations (because they are too slow), in order to save energy is questionable. The brain, which is 2% of the body’s weight and contains less than 1 per thousand of the body’s cells, consumes about 25% of the energy of the entire body, both at rest and in action. Active, focused thinking varies this value by just one percentage point, so normal passivity of the brain probably does not result in a significant energy gain. On the other hand, “shutting down” the PFC caused by massive stress could reduce energy consumption.13
The cooperation between the new and old parts of the brain is presented in a wonderfully understandable and entertaining way by Nobel Prize winner Daniel Kahneman in his extremely readable book “Fast Thinking, Slow Thinking”.14
4.3. Stress benefits of distractibility, task switching problems, and attention problems
ADHD sufferers do not have a disorder of the ability to pay attention per se. They can (in some situations) show very good attention and concentration. Anyone who has experienced an ADHD sufferer in hyperfocus, in which even highly monotonous activities can be carried out in a highly concentrated manner for hours on end, provided that they are highly enough motivating to be able to arouse the personal interests of the sufferer, and in which all stimuli that are irrelevant (in relation to the respective interest) are completely blanked out, can confirm this from their own experience. Against this background, one could assume that in ADHD it is not the ability to pay attention and concentrate per se that is disturbed, but the directing of attention. However, in our opinion, this conclusion also falls short.
According to our understanding, in ADHD there is neither a (technical) impairment of attention, nor a (technical) impairment of attention directing, but the directing of attention is subject to a deviating mode (profile, leitmotif, program, pattern). This mode involves a stronger steering by personal needs compared to the profile of the steering of attention in a relaxed state. This steering profile seems to be advantageous in survival-threatening situations: things of high personal interest are focused even more than usual (task switching more difficult up to hyperfocus), attention is more quickly diverted from things of less interest to the person. Attention is then less focused and more broadly distributed. While the former allows an increased concentration on recognized and to be fought dangers, the latter causes a faster perception of and faster attention changes to hitherto unrecognized dangers during less important occupations.
If there are no such existence-threatening stressors, it is easier to focus attention on things that are not relevant to survival.
In the case of stress, attention must be focused primarily on the stressor that threatens survival. If there are no such existence-threatening stressors, it is understandable that attention can be directed more easily to things that are not relevant to survival. In this context, the concept of survival-relevant is the link to the concept of personal motivation: those who are exposed to a survival-threatening stressor must decide for themselves what this is and how best to counter it.
In ADHD, distractibility per se is not increased, but only the distractibility of tasks that are not considered important for problem solving out of personal interest. This can be seen, for example, in the fact that the attentional performance of ADHD sufferers in tests can correspond to that of nonaffected persons when the rewards are particularly high. See more at ⇒ Motivation shift towards own needs explains regulation problems.
The advantage of increased distractibility can be well understood if one imagines that the camp must be guarded at all times and approaching dangers should be immediately recognized even during a nice conversation with another around the campfire. So, during the evening campfire (or other activities that do not bind the interest much), it is advantageous from the point of view of stress to be distracted by every noise, movement or other “little things”. Those who were less “distractible” in times of danger had disadvantages - they discovered the attack or approaching danger later.
Problems with spontaneously completing one activity in favor of another are not, at first glance, an expedient response to a stressor. From the perspective of stress utility, task switching problems are diametrically opposed to the symptom of distractibility.
What is the advantage of being hard to break away from a task once you get involved with it?
According to this perception, the task switching problem occurs particularly when activities of special interest are performed. It is difficult for the person concerned to detach his attention from things that are of special personal interest - especially if the task switching request refers to something that does not correspond to the personal interest of the person concerned.
The advantage of task switching problems is when a source of danger is just being observed or pursued. At that moment, everything else is unimportant and it is an advantage not to be quickly distracted by this (personally motivated) activity. Those who allowed themselves to be distracted by trivialities during combat were at increased risk of losing the battle.
In the case of distractibility, as in the case of task switching requirements, it is primarily the controllability of attention that is affected. Under stress, attention must be and remain focused primarily on the stressor that threatens existence. This is reflected in the phenomenon of hyperfocus - stress-affected individuals can become completely absorbed in tasks that they inwardly consider important. If the affected person allows himself to be distracted from (survival) important tasks, he is at a disadvantage. With regard to less relevant tasks, however, it is advantageous if the affected person is easily distracted. In terms of increased vigilance against possible dangers, on the other hand, distractibility from unimportant things (things that the affected person assesses as unimportant) is useful and conducive to survival.
From this point of view it becomes clear that in distractibility, as in task switching requirements, attentional control is involved. In ADHD sufferers, it is not the attentional capacity per se that is altered, but its controllability and tractability. The picture drawn here could explain this steering ability impairment in such a way that attention during stress has to be directed primarily to the existence-threatening stressor. If there are no such existence-threatening stressors, it is understandable that attention can be directed more easily to things that are not relevant to survival.
It fits in with this that ADHD sufferers perform almost as well in tests of attention as non-affected persons when they are appropriately interested or rewarded15 This confirms that the ability to concentrate or inhibit is not impaired per se, but that the ability to pay attention and concentrate, as well as the ability to direct attention, depend solely on an existing personal interest. If sufficient motivation is created by appropriately (high) rewards (for which higher rewards are required in ADHD sufferers), the attentional ability of ADHD sufferers can match that of non-affected individuals. This phenomenon can distort the test accuracy of attention tests to such an extent that ADHD sufferers who are highly motivated and interested in the test do not show attention problems.
This confirms that the problem in ADHD is not a restriction of attentional capacity per se, and that the directing of attention also works in principle, although the directing of attention follows a different model, as would be helpful in an emergency condition threatening survival.
4.4. Stress benefits of procrastination aversion (e.g., impatience) and procrastination
The stress benefit of delay aversion is that the individual is less likely to postpone combating the stressor.
Stress conveyed: “See to it that the problem resolves itself immediately. You should not let a danger exist. Take care of your problem. Be active, do not let yourself go. If something stops you on your way to solving your problem, try to work around it.”
The stress benefit of “now is always” is at the heart of what stress seeks to do to protect our survival: defeat the danger, now, immediately, don’t rest until the danger is eliminated. E is no time to wait, it is a matter of survival.
At first, the coexistence of delay aversion and procrastination seems contradictory. However, both are typical and frequently described symptoms of stress and ADHD.
Here, too, the meaning of the symptoms becomes apparent when the motivability through personal interest is taken into account.
Things that are interesting enough to motivate trigger procrastination aversion and impatience, while things that cannot arouse the necessary personal interest are procrastinated.
Personally motivating means not only intrinsic interesting things, but all things that they pursue as their own interests. This can also be not wanting to be late for work, which would be an extrinsic incentive. Personally motivating means all things that do not belong to the intrinsically desired goals. This often includes annoying chores such as cleaning up, doing laundry, filing tax returns, or the like - things that are not necessary for survival.
From the perspective of stress assuming a situation that threatens survival, this division makes sense. Someone who is currently fighting for survival would do well to focus on this and to do everything that helps to combat the stressor as quickly as possible. Anything that gets in the way triggers unwillingness and discomfort. Impatience, not being able to wait, and doing things in a kind of inner rush are the logical result of this. Things, however, that do not help combat the stressor not only can wait, they are supposed to. Gathering nuts for the winter is quite rightly a lower priority in the face of a survival-threatening danger.
Not only unpleasant things are affected by this. Pleasant things are also procrastinated by ADHD and stress sufferers: the inability to enjoy, which sometimes extends to the inability to recover, arises from the same root.
This explains the frequently observed and studied phenomenon of devaluing distant rewards: Rewards that are more distant are valued less by ADHD sufferers than by nonaffected individuals. Rewards that can be expected immediately, on the other hand, are valued by ADHD sufferers in quite the same way as by non-affected people as well. Under the guiding principle of an acute existentially threatening stress situation, this differentiation makes sense: Survival is now. Everything else can wait.
4.5. Stress benefits of dysphoria during inactivity
Dysphoria with inactivity is an original and functional symptom of stress and ADHD and should not be confused with depression, in which this symptom has become extreme and dysfunctional. Treatment of dysphoria with inactivity with antidepressants is counterproductive.
⇒ Depression and dysphoria in ADHD
Dysphoria with inactivity means that (only) in the state of rest the mood of the affected person deteriorates. Examples are bad moods after coming home or during the first days of vacation (until recovery has lowered the stress level to such an extent that the stress symptom of dysphoria with inactivity disappears). A number of sufferers therefore prefer active vacations, although these do not always cover the increased need for recovery.
Mood is one of the strongest controlling elements of the psyche. Every individual unconsciously and spontaneously tries to do what is necessary to maintain a good mood.
If bad mood always comes with inactivity, the individual will try to stay active.
Staying active, not sitting back and not letting pleasurable pleasures distract you from fighting the stressor and thus continuing the fight against the stressor is the stress benefit of dysphoria in inactivity.
Persistent brooding can result from the same mechanism. Increased brooding is functional as long as constructive solution possibilities are sought in the process. Brooding also becomes dysfunctional above a certain level, e.g. when only thinking in circles and thereby missing the necessary sleep.
The purpose of dysphoria in inactivity seems to be to encourage the person to become active, to actively resist the stressor (“fight”) or to have energy ready for escape (“flight”).
If a person’s mood worsens whenever he becomes passive, this will (usually unconsciously, but very effectively) induce him to become and remain active. Increased activity usually increases the probability of survival.
The purpose is not to burden the person with a bad mood even during his struggle. A bad mood during the activity would rather reduce the performance of the activities and would have no control effect in favor of the survival probability (away from passivity, towards activity). Therefore, dysphoria is only present during inactivity.
4.6. Stress benefits of listlessness
A stress benefit of listlessness would not be plausible if one assumed a complete listlessness. However, this is usually not the case. Listlessness could be explained as a stress benefit if stress does not cause a general listlessness, but reduces the drive for things that are less suitable to combat the stressor and increases it for things that are suitable to combat the stressor (which depends on personal interests).
Listlessness is useful in dangerous situations when it relates to things that are not necessary to combat the stressor. Giving in to the spontaneous thought of going for a swim while the camp is being circled by enemies is not really conducive to survival.
In stress, as in ADHD, the drive is not completely absent. From the point of view of non-affected persons, however, the drive to start things that are meaningful for everyday life is missing. Especially for unpleasant irrelevant things like cleaning or tidying up the drive is actually missing. For personally sufficiently motivating things, however, the drive is still there.
Insofar as depression is seen as a reaction to even more severe and unmanageable stress, the all-encompassing listlessness that then occurs could be seen as a way of ending the struggle, of surrendering to the enemy.16
There are a number of studies on learned helplessness or hopelessness that even showed in animal experiments on dogs how they gave up trying to escape an electric shock (even if they had the opportunity again).17
As an evolutionary biological point of view, it could be argued in a very simplified way that if the opponent won and the individual was captured, it might have made sense to stop fighting in order to avoid being killed. This would fit with the fact that listlessness is directly coupled to depression and that in ADHD both symptoms come and go very quickly in parallel.
However, depression is far more often a consequence of inflammatory reactions than of an immune response, so this evolutionary biological view may be dubious.
More sophisticated theories describe depression in evolutionary biological terms as a useful strategy for guiding behavior. According to the Social Navigation Hypothesis (SNH), depression evolved to serve two complementary social problem-solving functions. First, depression induces cognitive changes that focus and enhance capacities for accurately analyzing and solving important social problems, suggesting a social rumination function. Second, the costs associated with the anhedonia and psychomotor disruption of depression may persuade reluctant social partners to provide help or make concessions through two possible mechanisms, honest signaling and passive, unintentional fitness extortion. Thus, depression may also serve a social motivational function.18
In contrast, the neurophysiological mechanisms of action that trigger depression (these are immunologically triggered inflammatory responses) can be explicitly viewed as the result of a functional stress coping response.19
4.7. Stress benefits of devaluing later rewards
The stress benefit is: Survival is now. Everything else, everything that comes later, is only relevant once the present challenge has been successfully mastered. Stress therefore promotes a focus on the here and now, on the immediate. This weakens interest in things that are not immediately important to the current problem solving. From the perspective of maximizing problem-solving competence for the (potentially survival-threatening) challenge that exists right now, weakening interest in things that will only provide an advantage later is logical and correct. It is evolutionary-biologically the logical consequence of a very correctly functioning attentional control: attention is preferentially directed to things necessary for survival, while interest in things irrelevant for this is attenuated. It follows that, from an evolutionary biological point of view, acute and massive stress causes neither an attentional nor a distractibility disordernor an attentional control disorder. On the contrary, all these systems function perfectly - they merely follow a different guiding pattern under severe stress. They correctly and functionally follow the guiding principle that is correct and conducive to survival under severe stress: survival first now and putting everything else on the back burner.
4.8. Stress benefits of aversion to inactivity
The evolutionary-biological stress benefit is likely to be that the individual develops increased activity to eliminate the stressor, or that pleasurable activities (enjoyment) distract from it.
“Make sure that the problem is solved immediately. A danger should not be allowed to exist.
Take care of your problem. Stay active, don’t get distracted.
If something is stopping you in your tracks to solve your problem, try to work around it.”
4.9. Stress benefits of inability to enjoy
The stress benefit of inability to enjoy lies in a focus on the stressor. Strong stress “says”: survival is important now - you can enjoy and recover later. In a healthy (short-term) stress response, this is correct and helpful. If, on the other hand, the stress response systems are permanently activated (as in ADHD-HI), this causes an inadequate ability to recover and can lead to a vicious circle.
Inability to enjoy and self-worth
Conceivably, this stress benefit would also be mediated by decreased self-worth. The intrusion (the inner (unconscious) guiding principle) for this would be “It is not my place to enjoy”. This would be completely correct from the point of view of a healthy stress system: Enjoying is only allowed again without danger when the acute threat has been overcome. Such a self-esteem reaction as an immediate stress consequence would then not be a cognitive conclusion. Self-esteem problems are a common symptom of stress overload. At the same time, the symptom of Rejection Sensitivity, which is often considered a cognitive consequence of a self-esteem problem, is, in this side’s experience, a directly neurophysiologically mediated ADHD symptom (see Rejection Sensitivity).
4.10. Stress benefits of high sensitivity
An increased ability to perceive can be helpful in stressful situations. Being able to see, hear or smell better increases the probability of survival in evolutionary biology.
In contrast, it is detrimental in the case of a permanently heightened stress reaction that is not based on any actual danger, because it additionally intensifies the stress.
4.11. The stress benefits of inner turmoil
4.11.1. Stress benefits of being internally driven
It is helpful to be active and on the go until the stressor is fought or passed. Being internally driven is at the core of what makes stress: it drives you to expend energy to confront the stressor.
Resting, relaxing does not make sense in the face of acute imminent danger (not even for the ADHD-I subtype). Only when survival is assured, only when the acute danger has been eliminated and the individual is safe again, is it possible, from an evolutionary-biological point of view, to relax without danger.
Constantly having to do something is another form of expression of being internally driven. It keeps the person constantly active in order to drive him or her to do something about the (supposed) stressor. From this point of view, this is a promising stress management strategy.
Why do ADHD-I sufferers react differently if hyperactivity is supposed to be a survival advantage?
ADHD-I sufferers, who like all other ADHD sufferers also suffer from chronic overactivation of the stress response systems, have different stress management patterns than the hyperactive-impulsive ADHD-HI type. ADHD-I sufferers are more likely to respond to stress by fleeing or playing dead than by hyperactivity. Deer, which remain quiet for a long time when danger approaches to avoid detection, use a similar strategy (which they do not actively choose any more than humans choose their stress phenotype). But deer are also extremely tense internally when they do this. This is because if they do get spotted, they have to flee quickly. This explains why ADHD-I sufferers are not internally relaxed even when they “dream away.”
Why are there different stress response patterns?
For the survival of a species, it is helpful if a group has members with as different stress reaction phenotypes as possible. If all of them were to hit it immediately, the group would be extremely weakened, if waiting and keeping still would have been the better reaction in this case - and vice versa. A group can compensate the loss of individual members better than the loss of a large part of its members. It fits to this explanatory model that the stress phenotype is not strictly passed on by parents to their children, but is subject to a high variance. This high variability helps the group to survive.
4.11.2. The stress benefit of dealing with the stressor / thought circling / rumination
Stress “wants” us to deal with the stressor. It often makes sense to worry about the stressor for so long, to deal with it until we come up with a solution or the stressor settles in some other way. This can lead to an intense inner preoccupation with the stressor, to the point of “not being able to think of anything else.”
Sometimes the constant “using thoughts on the stressor” turns into a permanent rumination, which is characterized by a recurring sequence of the same thoughts (in the absence of creative variations of the thoughts). Such circling of thoughts is usually not solution-constructive. It is therefore at best a fruitless consequence of the stress benefit “preoccupation with the stressor”.
If the partner complains “he/she is actually never there, never with me, in thoughts always somewhere else”, this can be the external view of a permanent preoccupation with the stressor or a circle of thoughts.
4.11.3. The stress benefits of “doing what you’re doing right now, mostly in a rush”
If stress had an interest of its own (which it doesn’t, it is - from an evolutionary biological point of view - only the collection of survival strategies that were so successful that their bearer was able to reproduce considerably more often and therefore inherit their success strategies more often), it would want us to take care of the existing problems in a very concentrated way. Evolutionary biology is not about enjoying problem solving, it is about surviving.
Only when the struggle for survival has been won, only when the stressor has disappeared, is there room for relaxation, enjoyment and the resulting recovery. Until then, a loan is taken out - one lives at the expense of enjoyment and recreation. Whether this loan can ever be repaid is not relevant at the moment of the struggle for survival. If the person does not survive, he does not need to recover.
4.11.4. Stress utility of “difficulty in quietly pursuing a leisure activity”
Just as stress serves to cause the individual to actively engage with the stressor, it serves to prevent relaxed indulgence in a pleasurable activity while there are potentially survival-threatening dangers.
4.12. Mood swings as stress benefit consequences
Mood swings are, in our view and from an evolutionary biological perspective, an expression of the shift in perception to the here and now that is triggered by stress in order to focus attention on the stressor. When perception focuses on the here and now, it stands to reason that mood will also follow the here and now more.
It is true that a negative self-image (you are not good enough, do more so that you survive, do not be satisfied with what you have done so far, stay active to become better) could also be a drive to change previous life habits and to master the acute challenge. However, the concepts of self-esteem understand it as a consequence of cognitive processes. It is therefore rather unlikely that negative self-worth is a direct consequence of stress.
4.12.1. Stress benefits of aggression
Aggressiveness increases the willingness to fight, just as fearfulness increases the willingness to flee.
Combat was much more important and beneficial at the time our stress systems were created than it is today.
The two stress benefits of aggressiveness and anxiousness seem contradictory at first glance. If aggressiveness is a stress benefit, how can anxiousness be equally useful?
Stress symptoms are not a uniform response to any stressor, but vary depending on which stressor occurs. It is obvious that neither an aggressive nor a fearful reaction is appropriate to the stressor hunger. In contrast, to some other stressors, an aggressive response (fight) or a fearful response (flight) is more appropriate.
However, it can be seen that people differ according to the extent to which aggressive or fearful forms of behavior predominate in them.
The apparent contradiction is resolved if one considers not only the stress benefit for the individual, but the stress benefit for the whole group or genus. See below under 13. individual variance of stress symptoms as survival benefit for group and genus.
4.13. Frustration intolerance as a stress benefit consequence
Frustration intolerance could be a consequence of the massively increased striving to eliminate the stressor. A stressor that threatens the existence of a person must be eliminated as quickly as possible. If individual solution approaches do not lead to the goal, it would be advantageous to then expend increased energy again to try other solution strategies.
Mind you, a simultaneous parameter is extreme time pressure, which is why the “smart” solutions of slow thinking are not helpful.
4.14. Stress Benefits of Rejection Sensitivity
A stress benefit of rejection sensitivity is not clear. It could lie in not spending one’s resources in difficult times on people for whom it is not certain that the investment will be reciprocated. However, this does not explain why rejection is so aversive and not just a selector of whom to turn to.
The increased risk of being expelled from the group as a result of rejection represents a particularly intense stressor of its own.
4.15. Stress benefits of Tend and Befriend
Tend and Befriend has the stress benefit of increasing bonding in dangerous situations.
Similar to aggression and fearfulness, which are preferentially trained depending on the stressor, and which have different stress benefits (fight versus flight), Rejection Sensitivity and Tend and Befriend simultaneously make sense side by side in an individual. The translation could be: Bond more strongly with those who reciprocate the affection and accept the bond, and stay away from those group members where you cannot be sure of a return on your investment in bonding.
In the case of borderline, this dualism is particularly extreme (whereby borderline patients are often unable to accept an attachment because they do not feel worthy of it and because the fear of losing an attachment is much greater than the benefit of the attachment itself).
In the times when the stress benefits of our stress systems were created, exclusion from a group was almost tantamount to a death sentence. At the same time, men still had a somewhat greater chance of surviving for a time as lone fighters and hunters, which could explain why tend-and-friend occurs more pronouncedly in women than in men.
4.16. Stress benefits of self-esteem problems
Anxiety as a symptom of stress aims at the saving escape.20
The feeling of constantly having to do something (above under hyperactivity / restlessness / being internally driven) is strongly associated with a subjective impression of the affected person of getting far too little done, of not getting anything done, of being an underperformer and insufficient.
This perception is the way in which stress ensures that the person remains active. The feeling of having achieved enough would pave the way for a certain satisfaction and thus for a permitted relaxation. But this would be dangerous in the case of an acute threat, as the stressor underlying the stress reaction, because it would weaken the drive to fight the threat.
Stress tells its bearer that his previous problem-solving strategies are not sufficient. Stress immediately conveys: “the way you are (so far), you are not okay - because you are in an extremely dangerous situation. Move, change, so that you survive. Furthermore, your previous stress management strategies have put us in this position. Therefore, you should not feel good with the way you are.”
That this is very directly to the detriment of self-esteem is natural. A high self-esteem would cause one to be satisfied with oneself as one is. Then there would be no reason to change anything about oneself. But stress alarms us precisely because something has to be changed.
Therefore, severe stress also loosens the neuronal circuitry in the brain in order to be able to dissolve the previous, dysfunctional problem-solving patterns that are mapped in the neuronal circuitry and to replace them more easily with new circuitry. Conversely, when stress is successfully managed, it strengthens and reinforces neural circuitry to anchor the most recently successful coping strategy more deeply in the brain and promote its automation.
4.17. Stress benefits of anxiety
Increased anxiety causes increased caution. When life-threatening circumstances (presence of predators) increase caution, this increases the probability of survival.
If the anxiety becomes so great that it no longer merely increases caution but inappropriately impairs the ability to act, the functional stress symptom of anxiety has become dysfunctional and crosses the threshold into anxiety disorder.
4.18. Stress benefits of inner emptiness and alexithymia
Inner emptiness is the logical consequence of focusing on the stressor (see above under Thought Circles). It is conducive to survival if fighting the stressor is the only thing that really counts. Nothing should distract from this, not even any perception of inner state, other desires or (even good) feelings. Feeling good might tempt you to just go on with it and be fine - instead of worrying about the threat.
4.19. Stress benefits of reduced/increased empathy
The stress benefit of reduced empathy could be greater selfishness in problem solving, resulting in an increased likelihood of survival. In the physical struggle for survival with an enemy, empathy for the enemy’s suffering is a hindrance.
Within a group, increased compassion for others is a bonding tool that counteracts exclusion from the group, which would be even more detrimental in dangerous times.
These opposing stress benefits might make it plausible that people who externalize their stress (ADHD-HI: fight) benefit from decreased empathy, whereas for people who tend to internalize their stress (ADHD-I: flight, play dead), increased empathy is beneficial (tend and be friend).
4.20. Stress benefits of Novelty Seeking
One conceivable stress benefit of novelty seeking would be the search for new ways and means of coping with challenges. From the individual’s point of view, however, this appears to be rather disadvantageous, since the expenditure of resources for this is likely to be too high and resources tend to be conserved during an extreme stress. Possibly the stress benefit lies in an advantage for the species.
Preference for high-risk sports has already been described as a possible consequence of stress.
4.21. Stress benefits of increased risk taking
A stress benefit from the affinity for risk and risky sports could result from the fact that their stimulus intensity is so great that those affected can (must) finally fully engage with something. A kind of hyperfocus could be induced.
It is also conceivable that risk-taking, which is a stressor in its own right, can mask the latent undefined stressor that exists in ADHD better than other activities that do not offer stressful stimuli and can therefore more easily fall into the category of “now not allowed pleasures”.
4.22. Stress benefits of communication problems
4.22.1. Stress benefits of “small talk is perceived as boring”
The purpose of stress is to focus the person’s interest on issues that will help him solve his problem. All other things are unimportant. Stress is therefore more successful when things that do not arouse the person’s interest seem unimportant and irrelevant.
This phenomenon becomes more understandable if one takes into account that the deviating control of attention during stress occurs primarily via the factor of motivability (which is reduced in ADHD). Things that the affected person himself personally considers interesting (in the case of stress, those things that can solve his problem) attract attention. When personal motivation is high, ADHD sufferers can also very well block out all other things (low distractibility). On the other hand, what others want the affected person to be interested in, without really doing it, is considered unimportant. Affected persons are very easily distracted from these things.
Even if someone has fully understood cognitively that it is good for him to be interested in something now (e.g. the binomial formulas or the grammar of the infinitive in order to get good grades and no trouble at home) and he also has the will to achieve good grades and not to annoy anyone at home, this still does not arouse any personal interest. Apart from that, good grades are not important here and now, and home is equally very far away in the classroom - and therefore uninteresting.
4.22.2. Stress benefits of “interlocutors barely get a word in edgewise”
The same explanation applies here as for the fact that small talk is perceived as boring. The hyperfocusing of affected persons on topics of interest to them causes a shift from personally less interesting to personally more interesting topics that are more suitable to motivate the affected person….
Since the acute problem of the person concerned is greater than the needs of others who are not currently under severe stress, this is even socially legitimate to a certain extent. It would be interesting to observe whether stress sufferers select according to this.
With the symptoms
- Speech diarrhea, eagerness to talk, word glut (Logorrheapolyphrasia)
- Speech fast and slurred
- Impulsive disregard for social rules
- Interferes in conversations / activities of others without being asked to do so
no stress benefit could be defined so far.
4.23. Organizational difficulties as a stress benefit consequence
Problems of organizing tasks and activities have no stress benefit of their own, because organizational ability is, after all, advantageous in solving serious problems. However, if you look at the examples that are given for this, they can be seen as a consequence of other stress benefits.
Stress shifts the person’s focus to the stressor, for example, to ensure acute survival. Someone who is in the process of putting out a fire in his bedroom very healthily has a diminished interest in a tidy living room than others for whom nothing is burning at the moment.
Stress centrally aims at a priority shift: “Take care of the stressor, now - everything else is unimportant at the moment and can wait.”
When such stress is a permanent condition (as it is in ADHD due to the shift in thresholds at which the stress systems kick in for uncontrollable stress), and as a result the priority shift is a permanent condition, it inevitably leads to many things not being able to be dealt with today, tomorrow, or actually anytime soon with the same priority and calmness that those around you bring to the table.
4.23.1. Not (being able to) keep promises or commitments to others as a stress benefit consequence
Again, there is no immediate stress benefit, but the impaired ability to keep promises or commitments to others is the result of the stress benefit of focusing on the stressor that is being fought at the moment. This is (also) achieved by making things that are not immediately useful for one’s survival at the moment seem less important. It is plausible that things of everyday life become relatively less important when the focus is shifted to the struggle for survival.
If an appointment is made, the focus of perception (at the moment of the appointment) is on this meeting. If the person would then have to go on the way, while he is busy with something else, the other thing is always more important, because it is just “now and here”. All things further away are less important from the point of view of the stress response. Stress is always a focus on the problem to be solved here and now and puts all other problems that are not immediately relevant at the moment on the back burner.
This explanation seems to us more immediate and comprehensible than the sources of time estimation errors and outline deficits mentioned in the literature so far.
4.23.2. Problems doing things in the right order as a stress benefit sequence
This symptom is also a consequence of the stress benefit of valuing the here and now more highly and taking everything else less seriously. Stress changes priorities. Things considered personally important are prioritized higher. From a stress perspective, this is highly expedient.
If a person is under acute severe stress (understandable to others), e.g. because a loved one is currently in hospital undergoing a serious operation, no one would expect him to assemble an Ikea cabinet in the right order at the first attempt. However, if the person concerned can contribute something to save the loved one, he will be able to concentrate on this much better, since this will arouse his personal interest sufficiently to motivate him.
In addition, greatly elevated norepinephrine (as is common in ADHD-I) impairs the PFC and thus working memory. The stress benefit here lies in the shift of behavioral control from slow precise brain areas (PFC) to fast imprecise planning brain regions, as this is more advantageous in fight or flight.
4.24. Stress benefits of impaired performance
See stress benefits of listlessness.
4.25. Stress benefits from feeling overwhelmed
Not the overload itself, but the feeling of being overloaded could be helpful from the point of view of stress to activate the person to make even more and greater efforts.
Against it speaks that a special joy in an activity would be even more effective for this.
The feeling of being overwhelmed could be aimed at thinking about how to solve the problem in another way or motivating to seek support and help.
4.26. Time estimation error as a stress benefit sequence
Time estimation errors have no direct stress benefit. However, they could be related to the fact that stress causes waiting and inactivity to be perceived as unpleasant in order to encourage the individual to become active right now.
Stress further wants the stressor to be fought immediately. Stress causes a deviant experience of time: now is important, everything else does not count. Stress-affected people have an altered perception to the effect that only what is right now is true and valid forever. This is reminiscent of a kind of temporal black-and-white thinking.
4.27. Stress benefits of sleep problems
The stress benefit of sleep problems could be (or be the consequence of) the promotion of ruminations and thought circles (rumination), the stress benefit of which is the intensive examination of the stressor and the search for ways out and solutions. Since stress is not designed as a long-term resolution strategy, the aspect that less recovery impairs resolution skills is less relevant. Poorer sleep might also promote easier awakening to approaching dangers.
5. Stress symptoms that are not typical ADHD symptoms
There are a number of stress symptoms that are not mentioned as ADHD symptoms in the ADHD literature. These are primarily physical stress symptoms.
For many, the differentiation within the explanatory model advocated on this side could be explained by the fact that they are secondary stress symptoms that are not directly mediated by the HPA axis - e.g., psychosomatic complaints such as abdominal pain or back pain.
Somatic complaints (with the exception of sleep problems) could be another type of stress that occurs significantly less in ADHD sufferers than in non-affected persons (under stress).21 This circumstance could be explained according to the model described in the introduction under 13.
However, the studies on this side (at low n) also indicate - earlier to our own astonishment - that somatic stress symptoms are clearly underrepresented in adult ADHD sufferers. Exceptions exist only for sleep disturbances (very clearly) as well as exhaustion states and muscle tension (still clearly). In contrast, all other somatic stress symptoms are less frequent than in non-affected persons.
5.1. Sexual problems / listlessness
Sexual problem with decreased libido is a symptom of stress.222324
Libido suppression is a direct effect of the stress hormone CRH.2526
Sexual problems or listlessness are not specific ADHD symptoms, but nevertheless occur frequently. In ADHD, disturbed sexuality is mentioned as a frequent comorbidity.27 Sexuality is further mentioned as an addictive object and means of tension relief in ADHD28
The number of sexual partners in ADHD is typically increased, and first sex occurs earlier on average than in non-affected individuals. A decrease in libido is mentioned in connection with medication in ADHD.29
5.2. Increasing muscle tension
Increased muscle tone (which usually occurs at night) can lead in the medium term, for example, to considerable back pain and even vertebral blockages. Back pain, from this point of view, is often a consequence of stress.
Against this background, it is correct not to understand these as immediate ADHD symptoms. This does not change the fact that they are common stress symptoms that can also occur in ADHD.
5.3. Exhaustion states
Exhaustion is mentioned as a symptom of stress.23
5.4. Cardiovascular complaints
5.5. Loss of appetite / ravenous hunger
Eating problems are not immediate ADHD symptoms, but often occur comorbidly.
Obesity is at least twice as common in ADHD as in the unaffected.
Eating disorders are up to 8 times more common in ADHD sufferers than in non-affected people
More on this in the article ⇒ ADHD, obesity and eating disorders.
At least in adults, there is a strong correlation between obesity and ADHD.31
ADHD sufferers with obesity show high impulsivity more often than ADHD sufferers with normal weight. Impulsivity could be the linking element between obesity and ADHD.32
Some people react to stress with changes in weight. Weight loss is just as possible as weight gain.
Weight gain as a stress response could be interpreted evolutionary-biologically as increased storage of energy in emergency situations. Since the stress systems are activated more frequently in ADHD (ADHD-I) or do not switch off cleanly and are therefore permanently activated (ADHD-HI), the obesity, which is more frequent than average in ADHD, could be understood as a symptom of stress in those affected.
Headache and migraine are not typical ADHD symptoms, but often occur comorbidly.
5.7. Abdominal pain
Abdominal pain appears to be more common in children with ADHD but not in adults with ADHD.
5.8. Immune system problems / frequent colds
Stress hormones (adrenaline, CRH, cortisol) are able to artificially boost the immune system for a certain time. For the species of Homo sapiens, it was simply conducive to survival, if in situations of hardship, in which survival had to be fought for, not exactly simple (avoidable) diseases were added. The stress hormones adrenaline and CRH therefore cause a (temporary) pro-inflammatory increase in the activity of the immune system.
However, on the one hand, this increase is energy-sapping, and on the other hand, during the first stress pause, it leads to the body now taking the necessary regeneration and actively combating illness - e.g. through fever and other mechanisms with which the body protects itself against pathogens.
This is the reason why professionally stressed people often get sick during the first week of vacation.
In addition to its stress symptom-mediating effects, cortisol also has the task of terminating the stress response (by inhibiting the hormones secreted at the beginning of the stress chain and thus limiting its own secretion over time). Cortisol simultaneously reduces the pro-inflammatory effects of adrenaline and CRH and instead promotes other immune responses directed primarily against bacteria and parasites. Depending on the direction in which the stress systems are out of balance, excessive inflammation (e.g. of the intestinal mucosa in crohn’s disease or of the skin in neurodermatitis) or excessive immune reactions against external pathogens (e.g. allergies) can occur.
5.9. Increasing respiratory rate
6. Individual variance in stress symptoms as a survival advantage for group and genus
The parallel occurrence of aggression and fearfulness in similar situations in different individuals is sometimes advantageous for some and sometimes for others. The parallel distribution among individuals is a survival advantage for the species. If members of a group have different stress responses, this ensures the survival of the group better than if all individuals had the same response.
If a particular stress response (e.g., impulsive-aggressive) is less well suited to successfully combat the stressor, only those individuals carrying that stress response phenotype are disadvantaged or at risk of extinction. If, on the other hand, the wait-and-flee or play-dead variant is less suitable, these individuals do not survive as well - while the more aggressive individuals have advantages.
In a group, it is also the case that, depending on personal aptitude, some individuals take charge of problem solving and others do not, thus providing advantages for the group as a whole.
Different stress response patterns increase the likelihood that at least some individuals in the group will survive.
7. Stress benefits explain difference ADHD / other mental disorders
Many symptoms of ADHD are functional stress symptoms. Functional means that they have a use for the individual in struggling with a stressor - assuming that there is an acute and massive threat to the individual’s existence.
The symptoms of most other mental disorders (anxiety, depression, compulsion) can be distinguished by the fact that they are usually stress symptoms that have become dysfunctional rather than functional. Dysfunctional means that there is no immediate stress benefit of the core symptom(s).
The level of listlessness and hopelessness that characterizes depression is not conducive to combating the stressor.
One could perhaps see a stress benefit in the fact that the active fight against the stressor is now lost, and that it is more conducive to survival to come to terms with this than to continue to fight against the stressor, since this could involve further loss of energy and above all the risk of being killed. This would recognizably be a different state of fighting against a stressor. However, this idea potentially overstretches the stress benefit picture.
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