Emotional dysregulation - neurophysiological correlates

Emotional dysregulation in ADHD (and autism) has been linked to specific dopaminergic gene variants in one study.¹ Neurophysiological correlates have not yet been found.²

• 1. Neurophysiological elements of the regulation of emotion and mood
• 2. Emotional dysregulation in ADHD: sympathetic and parasympathetic nervous system
• 3. Reduced ability to induce and regulate emotions
• 4. Working memory and emotional dysregulation
• 5. Correlation of emotional dysregulation with hyperactivity and inattention
• 6. Correlation of emotional dysregulation with fractional anisotropy of the white matter of the brain
• 7. Empathy
• 8. Emotional reactions as an early indicator of ADHD in infants
• E. Excursus: Treatment of emotional dysregulation
  • E.1 Medication of emotional dysregulation
  • E.2 Psychotherapeutic treatment of emotional dysregulation

1. Neurophysiological elements of the regulation of emotion and mood¶

Emotions are processed in the PFC primarily in Brodman area 9 (BA9, including dlPFC).³ Motor functions are controlled by BA 8, memory by BA 10 and emotion-related sensory functions by BA 11.

Emotion and mood are controlled by limbic-cortical-striatal-pallidal-thalamic circuits, consisting of connections between⁴⁵

• PFC
  • Orbitalmedial
    • Decision making
    • Emotional behavior
    • Reward-oriented behavior
    • Inhibition of impulsive behavior
      • Reduced dopaminergic excitation of the omPFC reduces its ability to inhibit impulsive behavior⁶
  • Orbital
    • Nutrition-related information
    • Expectation of rewards
    • Linking stimuli with a reward, in particular with the reward value of the stimulus
  • Medial
    • Decision-making, emotional and reward-oriented behavior
    • Projected onto control centers of the internal organs in the hypothalamus and periaqueductal gray
    • Modulation of the activity of the internal organs in response to affective stimuli
      • Breathing rate
      • Heart rate
      • Blood pressure
      • Digestion
    • Increased activity of the mPFC correlates with increased skin conductance, which in turn correlates with increased activity of the sympathetic nervous system, which is associated with increased emotional arousal
  • Dorsolateral
    • Selection of where attention should be focused
• Striatum
  • Dorsal
    • Caudate nucleus
      • Its size correlates negatively with anhedonia
  • Ventromedial
    • Nucleus accumbens
    • Olfactory bulb
    • Globe Pallidum
      • Its size correlates negatively with anhedonia
    • Ventral pallidum
      • Its size correlates negatively with anhedonia
• Hippocampus⁷
  • Ventral
    • Subiculum
  • Putting fear into context
  • Increase or decrease anxiety response based on past experiences and memories
  • A connection is assumed between stress-related impaired hippocampus and emotional dysregulation, especially anxiety⁷
• Thalamus
  ⇒ Thalamus
  • Mediodorsal
  • Midline
• Amygdala
  ⇒ The amygdala - the stress conductor
  • Crucial for
    • Emotional learning
    • Fear conditioning
  • Conveys emotional reactions to stress

This network uses reciprocal connections with

• Cortical regions that control higher cognitive functions
• Regions that control autonomic functions, including
  • Periaqueductal gray
  • Hypothalamus

to balance higher cognitive functions with information from the body organs and external environmental conditions to influence mood and emotional states.⁸

Connections between oPFC / mPFC and the dlPFC mediate neurophysiological correlations in mood disorders between⁹¹⁰¹¹

• Mood dysregulation
• Working memory problems
• Impairment of cognitive flexibility

Injuries to the right orbitofrontal PFC caused disinhibited emotional responses and inappropriate social behavior, including a blunted response to punishment, as well as (possibly only early in life) social and moral judgment problems.¹²

The impairment in the processing of negative emotional stimuli was associated with increased activity in the left anterior insula up to the inferior frontal gyrus.¹³

One study found evidence that emotional dysregulation was the symptom linking ADHD and gambling addiction.¹⁴

2. Emotional dysregulation in ADHD: sympathetic and parasympathetic nervous system¶

Several studies found deviations in the sympathetic and parasympathetic nervous system response in persons with ADHD that correlated with the emotional dysregulation of the people with ADHD.

According to this, healthy children show systematic variations in parasympathetic activity (RSA) depending on emotion valence (stronger activation for negative emotions, lower activation for positive emotions) and task demand (stronger activation for suppression than for induction). In contrast, children with ADHD showed a stable pattern of increased parasympathetic activity (RSA) in all task conditions compared to baseline.¹⁵

A more comprehensive replication study confirmed this and found that in ADHD, emotional negative and positive stimulation tasks correlated with significantly increased parasympathetic and sympathetic reactivity.¹⁶

Vagally mediated high-frequency heart rate variability correlates with deficits in emotional self-regulation across the lifespan in ADHD.¹⁷

3. Reduced ability to induce and regulate emotions¶

In an imaging study, compared to healthy control subjects¹⁸

• deviating activation and deactivation patterns during emotion regulation
• a lower volume of gray matter in limbic and paralimbic areas
• a larger volume of gray matter in visual and cerebellar areas

The behavioral and functional deficits of emotion induction and regulation in ADHD were not normalized by stimulants.¹⁸

4. Working memory and emotional dysregulation¶

Deficits in working memory can contribute to emotional dysregulation.¹⁹ Working memory is linked to emotion regulation.
A study of children with ADHD aged 6 to 16 years examined the interplay between identified working memory/emotion regulation patterns, demographic characteristics, and the role of comorbid diagnoses. Two different, unchanging, non-restricted classes of working memory/emotion regulation were found:²⁰

• Class 1 (62 %):
  • Impaired working memory
    • significantly lower values in the digit span test
  • Emotion regulation consistently functional
• Class 2 (emotionally dysregulated):
  • average working memory scores
  • increased emotion regulation problems.

Working memory indicators and emotion regulation scores measured by parents (not teachers) correlated only slightly.
There was no correlation between class and comorbid diagnoses, age, gender or verbal IQ.

5. Correlation of emotional dysregulation with hyperactivity and inattention¶

One study found a link between hyperactivity/impulsivity and emotional dysregulation, but not between inattention and emotional dysregulation.¹⁹

In contrast, another study found that emotional dysregulation seems to correlate more with inattention than with hyperactivity/impulsivity.²¹ Higher inattention correlated here with

• Reduced emotional clarity, which increased difficulties in interpersonal relationships
• Less access to emotion regulation strategies, which increased the symptom burden
• Impairments at school and at work.

6. Correlation of emotional dysregulation with fractional anisotropy of the white matter of the brain¶

The fractional anisotropy of 19 white matter lanes labeled with

• Affective-processing
• Sensory-processing
• Integrating
• Cognitive

Control circuits were positively correlated with the severity of emotional dysregulation in non-affected people, while they were negatively correlated with emotional dysregulation in people with ADHD.
The severity of ADHD symptoms and diagnosis correlated negatively with fractional anisotropy of these white matter tract bundles, whereas intelligence correlated positively.²²

7. Empathy¶

Empathy is divided into emotional (affective) empathy and cognitive empathy. Emotional empathy develops earlier than cognitive empathy. Emotional empathy uses limbic and paralimbic regions of the brain. Cognitive empathy requires a finely tuned maturation of prefrontal and temporal networks. Injuries to the ofPFC, the vmPFC or right parietal brain regions impair both types of empathy.²³
Emotional empathy is thought to be influenced by the oxytocinergic system, whereas²⁴ cognitive empathy is thought to be influenced by the dopaminergic system.²⁵
Although emotional and cognitive empathy work independently of each other, they appear to influence each other. Emotional empathy is seen as an automatic bottom-up process, while cognitive empathy is described as a top-down modulator.²³

8. Emotional reactions as an early indicator of ADHD in infants¶

Specific emotional reactions occur in children of parents with ADHD as early as 6 months of age.²⁶

E. Excursus: Treatment of emotional dysregulation¶

E.1 Medication of emotional dysregulation¶

In our opinion, emotional dysregulation benefits somewhat less from drug treatment than other symptoms of ADHD. Particularly sensitive medication adjustment is required here.
In our experience, medications such as atomoxetine or guanfacine are particularly helpful for emotional dysregulation.

Experience has shown that stimulants (e.g. methylphenidate) not only improve attention and reduce hyperactivity and impulsivity, but also improve emotional self-regulation, which may be at least partly a consequence of reduced impulsivity ^{27 28 2930}
In contrast, another study found that behavioral and functional deficits in emotion induction and regulation in ADHD were not normalized by stimulants.¹⁸

Barkley explained in a lecture,³¹³² that stimulants can dampen emotions by inhibiting the limbic system, which is not affected in ADHD per se. The higher the dosage, the more the limbic system (including the amygdala) is inhibited. This naturally reduces affect. An individually excessive stimulant dosage can therefore lead to a restricted emotional experience, which occurs in around 20 % of patients treated with stimulants.
In this context, Barkley refers to the increasingly frequent use of combination medication (stimulants and atomoxetine or stimulants and guanfacine) in order to cumulate the positive effects and spread the side effects, which are usually located in different areas, and thus reduce them. In contrast to stimulants, atomoxetine does not affect the limbic system and therefore does not impair emotional perception. Atomoxetine activates the ACC and the frontal lobe and thus directly influences executive functions. Stimulants improve attention, cognition, executive functions and working memory. They are less suitable for improving emotion regulation.
In our opinion, a dampening effect of stimulants on the limbic system would be particularly helpful in cases of excessive impulsivity or anxiety, while people with ADHD who are more emotionally balanced should dose stimulants rather carefully and reduce stimulants at the latest when their emotional perception is impaired and, if necessary, augment them with other substances or switch completely to other active ingredients.

A strikingly high number of people with ADHD reported that their rejection sensitivity decreased significantly when taking stimulants. Individual people with ADHD (about 10 %) reported that MPH increased RS, whereby even switching to another MPH preparation showed differences.

Comorbid anxiety disorders, depression and aggression can be exacerbated by stimulants, as anxiety and moods are regulated by the dopaminergic activity of the ventromedial prefrontal cortex in conjunction with the limbic system. In these cases, noradrenaline reuptake inhibitors or α2A adrenergic agonists are recommended instead.³³
One (quite small) study found no short-term change in state anxiety with a single dose of MPH, but did find evidence of a possible long-term worsening.³⁴
Amphetamine medications have been shown to have better effects on mood in ADHD.

According to a (very small, n = 26) study, memantine (given in addition to stimulants) is said to further improve emotional executive functions and self-regulatory functions.³⁵

E.2 Psychotherapeutic treatment of emotional dysregulation¶

Mindfulness training is able to improve the balance between thinking and feeling, which is shifted towards thinking in ADHD-typical alexithymia (lack of emotion).

Exercises such as those done with trauma patients, who also often suffer from a lack of emotion, can improve the perception of emotion.

The 5-4-3-2-1 exercise³⁶

1. Sit quietly and breathe consciously.
2. Look around you and name 5 things you see.
3. Now name 5 things that you hear. If there are fewer, name them several times.
4. Now close your eyes. Name 5 things that you feel.
5. Repeat the exercise with 4 things instead of 5, then with 3, then with 2 and again with 1 thing.

Further sources:

Smart but Stuck: Emotions in Teens and Adults with ADHD; Thomas E. Brown (Jossey-Bass/Wiley, 2014).