International Behavioral Neuroscience Society 12th Annual Meeting (23-27 April 2003; San Juan, Puerto Rico)

Fronto-executive functions in rodents: neural and neurochemical substrates
Cardinal, R.N.; Dalley, J.W.; Passetti F.; Theobald, D.E.; Winstanley, C.A.; Robbins, T.W.
Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, UK.

The prefrontal cortex (PFC) and associated cortico-striatal circuitry, including interconnections with sensory neocortical and motor systems has been widely implicated in the control and execution of goal-directed behaviour, particularly in executive aspects of attentional processing. Such control mechanisms serve to optimize performance when complex sequences of behaviour are required or when pre-potent responses need to be inhibited in order to achieve a later goal. This paper examines the nature of the cognitive control processes that contribute to executive functioning, the neural circuitry underpinning such processes and the distinct and separable contributions of the monoamine and cholinergic transmitter systems that modulate PFC function. Data will be presented from two rodent paradigms; namely the 5-choice serial reaction time task, which assesses executive aspects of visuo-spatial attention and a delay-of-reward paradigm, which assesses aspects of impulsivity. The results reveal dissociable functions of distinct fronto-striatal subregions and serotonergic receptor subtypes in attention, impulsivity and inhibitory response control as well as important differences in the behavioural contingencies that specifically affect noradrenaline, dopamine, serotonin and acetylcholine release in the PFC. The relevance of these findings to the pathophysiology and treatment of schizophrenia and attention-deficit hyperactivity disorder will be discussed. This work was supported by the Wellcome Trust and an MRC Center Grant in Clinical and Behavioral Neuroscience.