Thinking blocks and decision-making problems in ADHD - neurophysiological correlates
Thinking blocks occur equally in ADHD-HI and ADHD-I. Contrary to a view previously expressed here, they are not subtype-specific. Decision-making problems, on the other hand, appear to occur significantly more frequently in ADHD-I than in ADHD.
This suggests that the two manifestations have different neurophysiological correlates.
ADHD is associated with impaired learning behavior in response to changing rewards, which leads to impaired decision-making behavior. A neurophysiological correlate was found to be a reduced representation of choice probability in the left posterior parietal cortex in ADHD. The impairment of flexible behavior in ADHD was due to excessive choice switching (“hyperflexibility”), which can be detrimental (when environmental conditions remain constant) or beneficial (when environmental conditions change), depending on the learning environment 12
An improved response to changing environmental conditions can be beneficial in stressful situations. We see a correlation here with functional stress symptoms.
The extremely high levels of noradrenaline during severe stress impair the functionality of the PFC. While slightly elevated noradrenaline levels increase the ability to think, very high noradrenaline levels reduce this ability and behavioral control is transferred from the PFC to the posterior cortex.3456
The details can be found in the article ⇒ Neurotransmitters during stress In the section ⇒ Severe stress = strong increase in NE/DA and cortisol = reduced cognitive performance.
Aster HC, Waltmann M, Busch A, Romanos M, Gamer M, Maria van Noort B, Beck A, Kappel V, Deserno L (2024): Impaired flexible reward learning in ADHD patients is associated with blunted reinforcement sensitivity and neural signals in ventral striatum and parietal cortex. Neuroimage Clin. 2024 Mar 1;42:103588. doi: 10.1016/j.nicl.2024.103588. PMID: 38471434. ↥
Hauser TU, Iannaccone R, Ball J, Mathys C, Brandeis D, Walitza S, Brem S (2014): Role of the medial prefrontal cortex in impaired decision making in juvenile attention-deficit/hyperactivity disorder. JAMA Psychiatry. 2014 Oct;71(10):1165-73. doi: 10.1001/jamapsychiatry.2014.1093. PMID: 25142296. ↥
Ramos, Arnsten (2007): Adrenergic pharmacology and cognition: focus on the prefrontal cortex. Pharmacol Ther. 2007 Mar; 113(3):523-36., Kapitel 6 ↥
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Ramos, Colgan, Nou, Ovadia, Wilson, Arnsten (2005). The beta-1 adrenergic antagonist, betaxolol, improves working memory performance in rats and monkeys. Biol. Psychiatry 58, 894–900. ↥
ähnlich: Arnsten (2000): Stress impairs prefrontal cortical function in rats and monkeys: role of dopamine D1 and norepinephrine alpha-1 receptor mechanisms. Prog Brain Res. 2000;126:183-92. ↥