Prefrontal dopamine levels determine the balance between cognitive stability and flexibility
S J Fallon1, C H Williams-Gray, R A Barker
1Medical Research Council Cognition and Brain Sciences Unit, Cambridge CB2 2EF, UK. s.fallon@donders.ru.nl
Cerebral Cortex (New York, N.Y. : 1991)
|February 22, 2012
Summary
The COMT val158met polymorphism influences attentional set formation, crucial for goal-oriented behavior. Dopamine levels in the prefrontal cortex, modulated by this gene, impact cognitive control differently in Parkinson's patients versus healthy older adults.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Genetics
Background:
- Attentional set formation, a prefrontal cortex (PFC) mechanism, supports goal-directed behaviors by creating attentional biases.
- The catechol O-methyltransferase (COMT) val158met polymorphism is hypothesized to modulate PFC dopamine (DA) levels, potentially affecting attentional set formation.
Purpose of the Study:
- To investigate the effect of the COMT val158met polymorphism on attentional set formation in older adults.
- To compare these findings with existing data from Parkinson's Disease (PD) patients.
Main Methods:
- Functional magnetic resonance imaging (fMRI) study.
- Analysis of COMT val158met polymorphism's impact on set-like behavior and right dorsolateral PFC (DLPFC) activation.
- Comparison with preexisting data from PD patients.
Main Results:
- PFC DA levels predict attentional set formation and DLPFC activation.
- In PD patients, val homozygotes exhibited increased DLPFC activation and set-like behavior.
- In healthy older adults, the opposite pattern was observed, with met homozygotes showing greater set-like behavior.
Conclusions:
- The interaction between COMT genotype and PD status supports an inverted-U shaped relationship between PFC DA levels and attentional set formation.
- Findings align with studies showing altered PFC DA in early PD.
- Modulation of PFC DA by COMT genotype plays a significant role in cognitive control mechanisms like attentional set formation.
Related Concept Videos
01:14Role of Cerebellum and Prefrontal Cortex in Memory
The cerebellum, while traditionally associated with motor control, also plays a crucial role in memory, particularly in procedural memory, which involves learning motor tasks that become automatic through repetition. For example, studies have shown that when the cerebellum is damaged, individuals or animals lose the ability to learn conditioned motor responses, such as the conditioned eye-blink response in classical conditioning experiments with rabbits. This study demonstrates the cerebellum's...
01:30Cognitive Development During Adulthood
Cognitive development continues throughout adulthood, undergoing significant shifts across early, middle, and late stages. Individual transition occurs from adolescent idealism to pragmatic and adaptable thinking in early adulthood. During this period, individuals learn to integrate personal beliefs with the recognition that other perspectives are equally valid. Exposure to the complexities of modern society, diverse experiences, and higher education contribute to this adaptive thought process,...
01:30Attention-Deficit/Hyperactivity Disorder
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by persistent inattention, hyperactivity, and impulsivity. It affects approximately 5-8% of children globally, with around 60-70% of cases persisting into adulthood. ADHD has significant implications for educational attainment, social interactions, and occupational success.
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.
01:23Role of Neurotransmitters in Memory
Neurotransmitters are integral to the brain's communication system, enabling neurons to transmit signals across synapses. This chemical exchange underpins various cognitive functions, including memory processes. The role of neurotransmitters in memory is multifaceted, influencing the encoding, consolidation, and retrieval of memories through their action on different neural circuits.
Glutamate and Synaptic Plasticity
Glutamate, the brain's main excitatory neurotransmitter, is critical for...
Glutamate and Synaptic Plasticity
Glutamate, the brain's main excitatory neurotransmitter, is critical for...
01:19High-Level and Low-Level Awareness
Controlled processes in human consciousness represent high-alert mental states where individuals deliberately focus their attention on achieving specific goals. Controlled processes can be seen in situations like mastering new technology, where a person might become so absorbed that they ignore surrounding distractions. Such processes involve selective attention, requiring one to concentrate on particular elements of experience while disregarding others. These are governed by executive...
01:30Organization of the Brain
The brain is an integral component of the nervous system and serves as the center for processing sensory inputs, making decisions, and directing bodily actions. This complex organ is organized into three primary sections: the hindbrain, midbrain, and forebrain, each responsible for a range of vital functions.
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...