CONICET | Buscador de Institutos y Recursos Humanos

Temporal processing in the seconds-to-minutes range, known as interval timing, is a crucial cognitive function that requires activation of cortico-striatal circuits via dopaminergic/glutamatergic pathways. Interval timing is altered in disorders associated with pathological dopaminergic function, including schizophrenia, Parkinson's disease, and Huntington's disease. It has been reported that children and adults with autism spectrum disorders(ASD) are impaired in their ability to accurately perceive time. In the present study, a mouse model of autism - which involves prenatal exposure to valproic acid (VPA) at gestational day 12.5 - was evaluated for its ability to acquire timing responses in simultaneously trained 15-s and 45-s peak-interval (PI) procedures. In the PI procedure, subjects are first trained on a fixed-interval (FI) schedule of reinforcement and then transitioned to the PI protocol in which unreinforced probe trials are introduced. With repeated experience on probe trials, subjects learn to respond at a time closer to the expected time of reinforcement, producing a Gaussian-shaped response function. Our results indicate that both male and female VPA-mice showed significant impairments in timing accuracy and precision compared to control (saline) groups. These deficits in temporal processing in a mouse model of autism are consistent with previous results in humans, and provide a useful tool for further behavioral and pharmacological studies.

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