Decision making related activity in the dorsal striatum for the timely execution of actions

MARTÍNEZ, MARÍA CECILIA; MURER, MARIO GUSTAVO; BELLUSCIO, MARIANO

Córdoba

Congreso; XXXIII Congreso Anual SAN; 2018

Sociedad Argentina de Neurociencias

Corticostriatal circuits are involved in the selection and execution of sequences of movements in order to maximize the profit derived from them. With the aim of studying how actions are triggered at the right time in a self-initiated rewarded task, we used tetrodes to record the striatal activity. Briefly, after a minimum inter-trial interval (ITI), water-deprived rats must enter a nosepoke and, following a visual cue, emit an eight-licks sequence onto a tube to receive water. First, we found a modulation of the striatal activity that peaks right before the beginning of the trials. This activity is related to the waiting time and it differs between timely and premature nosepoke entries. Interestingly, such activity profile was also observed when the ITI was duplicated. In a third series of experiments, subjects had to enter the nosepoke in a restricted time window: if they entered prematurely or late, they received no reward. In this version of the task we found that the anticipatory activity was maximum when the animal entered the nosepoke within the rewarded time window. Considering that subjects must estimate the right time to perform a sequence of actions to obtain the reward, we hypothesize that this anticipatory neuronal activity codes for the reward expectancy associated to the time chosen for the initiation of the learned action and it is involved in its timely execution.