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Chiuffa Tunes, G.

Publications and source records attributed to Chiuffa Tunes, G..

3 recordsLinked to original sources

Time-Encoding Migrates from Prefrontal Cortex to Dorsal Striatum During Learning of a Self-Timed Response Duration Task

Although time is a fundamental dimension of life, we do not know how the brain encodes the temporal information. Several brain areas underlie the temporal information, such as the hippocampus, prefrontal cortex, and striatum, but evidence of how they cooperate to process temporal information is scarce. Notably, the analysis of neural activity during learning are rare, mainly because timing tasks usually take a long time to train. Here we investigated how the time encoding evolves when animals learn to time a 1.5 s interval. We designed a novel training protocol where rats go from naive- to proficient-level timing performance within a single session, allowing us to investigate neuronal activity from very early learning stages. We used pharmacological experiments and machine-learning algorithms to evaluate the level of time encoding in the medial prefrontal cortex and the dorsal striatum. Our results show a double dissociation between the roles of the medial prefrontal cortex and the dorsal striatum during temporal learning, where the former commits to early learning stages while the latter become more engaged as animals become more proficient in the task.

neuroscience↗

Temporal learning among prefrontal and striatal ensembles

Behavioral flexibility requires the prefrontal cortex and striatum. Here, we investigate neuronal ensembles in the medial frontal cortex (MFC) and the dorsomedial striatum (DMS) during one form of behavioral flexibility: learning a new temporal interval. We studied corticostriatal neuronal activity as rodents trained to respond after a 12-second fixed interval (FI12) learned to respond at a shorter 3-second fixed interval (FI3). On FI12 trials, we discovered time-related ramping was reduced in the MFC but not in the DMS in two-interval vs. one-interval sessions. We also found that more DMS neurons than MFC neurons exhibited differential interval-related activity on the first day of two-interval performance. Finally, MFC and DMS ramping was similar with successive days of two-interval performance but DMS temporal decoding increased on FI3 trials. These data suggest that the MFC and DMS play distinct roles during temporal learning and provide insight into corticostriatal circuits.

neuroscience↗

Rats can learn a temporal task in a single session

Fixed interval, peak interval, and temporal bisection procedures have been used to assess cognitive functions and address questions such as how animals perceive, represent, and reproduce time intervals. They have also been extensively used to test the effects of drugs on behavior, and to describe the neural correlates of interval timing. However, those procedures usually require several weeks of training for behavior to stabilize. Here, we compared three types of training protocols and reported a procedure in which performance by the end of the very first session nearly matches the performance of long-term training. We also discuss this fast-learning protocol in terms of an information-theory approach. This one-day training protocol can be used to investigate temporal learning and may be especially useful to electrophysiological and neuropharmacological studies.

neuroscience↗