Learning and cognitive flexibility: frontostriatal function and monoaminergic modulation.
Learning in a constant environment, and adapting flexibly to a changing one, through changes in reinforcement contingencies or valence-free cues, depends on overlapping circuitry that interconnects the prefrontal cortex (PFC) with the striatum and is subject to several forms of neurochemical modulation. We present evidence from recent studies in animals employing electrophysiological, pharmacological and lesion techniques, and neuroimaging, neuropsychological and pharmacological investigations of healthy humans and clinical patients. Dopamine (DA) neurotransmission in the medial striatum and PFC is critical for basic reinforcement learning and the integration of negative feedback during reversal learning, whilst orbitofrontal 5-hydroxytryptamine (5-HT) likely mediates this type of low level flexibility, perhaps by reducing interference from salient stimuli. The role of prefrontal noradrenaline (NA) in higher order flexibility indexed through attentional set-shifting has recently received significant empirical support, and similar avenues appear promising in the field of task switching.
Kehagia
Angie A
AA
Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing Street, Cambridge CB2 3EB, UK. ak423@cam.ac.uk
Murray
Graham K
GK
Robbins
Trevor W
TW
D000818:Animals; D001288:Attention / Q000502:physiology; D015306:Biogenic Monoamines / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D003342:Corpus Striatum / Q000033:anatomy & histology / Q000502:physiology*; D056344:Executive Function / Q000502:physiology; D006801:Humans; D007858:Learning / Q000502:physiology*; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology
D015306:Biogenic Monoamines