Dorsal striatum coding for the timely execution of action sequences

MARTINEZ MC; ZOLD CL; COLETTI MARCOS; MURER MG; BELLUSCIO MA

eLife

eLife Sciences Publications Ltd

Año: 2022

The automatic initiation of actions can be highly functional. But occasionally these actions cannotbe withheld and are released at inappropriate times, impulsively. Striatal activity has been shown toparticipate in the timing of action sequence initiation and it has been linked to impulsivity. Using a selfinitiatedtask, we trained adult male rats to withhold a rewarded action sequence until a waiting timeinterval has elapsed. By analyzing neuronal activity we show that the striatal response preceding theinitiation of the learned sequence is strongly modulated by the time subjects wait before eliciting thesequence. Interestingly, the modulation is steeper in adolescent rats, which show a strong prevalence ofimpulsive responses compared to adults. We hypothesize this anticipatory striatal activity reflects the animals´ subjective reward expectation, based on the elapsed waiting time, while the steeper waitingmodulation in adolescence reflects age-related differences in temporal discounting, internal urgency statesor explore-exploit balance.