Neural Circuits and Systems Neuroscience
Author: Maria Cecilia Martinez | email: ceciliamartinez256@gmail.com
Maria Cecilia Martinez 1°, Camila Zold 1°, Marcos Coletti 1°, Gustavo Murer 1°, Mariano Belluscio 1°
1° Laboratorio de Fisiología de Circuitos Neuronales, Grupo Neurociencia de Sistemas, IFIBIO-Houssay, Facultad de Medicina, Universidad de Buenos Aires-CONICET
2° Dto. Fisiología y Biología Molecular y Celular, FCEN, UBA.
The automatic initiation of actions can be highly functional. But occasionally these actions cannot be withheld and are released at inappropriate times, impulsively. Striatal activity has been shown to participate in the timing of action sequence initiation and it has been linked to impulsivity. Using a self-initiated task, we trained adult male rats to withhold a rewarded action sequence until a waiting time interval has elapsed. By analyzing neuronal activity we show that the striatal response preceding the initiation of the learned sequence is strongly modulated by the time subjects wait before eliciting the sequence. Interestingly, the modulation is steeper in adolescent rats, which show a strong prevalence of impulsive 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 waiting modulation in adolescence reflects age-related differences in temporal discounting, internal urgency states or, explore-exploit balance.