Role of the medial prefrontal cortex in contextual memories acquisition that depend on temporal processing between discontinuous stimuli

Abstract

Timing is a universal component of sensory and motor processing, cognition and learning. Spatial and temporal processing in establishing relations between events is an intrinsic part on our day by day perceptions, being essential for normal and adapted behavior. Auditory trace fear conditioning is a model that has been successfully used to experimentally reproduce aspects of learning that depends on the association of stimuli temporally discontinuous. Similarly to unimodal stimulus like a tone, the context may also be associated with an aversive stimulus present after it and in a temporal discontinuous manner. This has been assessed through a phenomenon called context pre-exposure facilitation effect, in which a context pre-exposure is followed by a time interval between a new exposure with the present of an aversive stimulus. However, how and if the time interval affects the neural circuits that underlie learning, and whether this would occur in a gradient-dependent manner, remains to be further investigated. Since prefrontal cortex (PFC) has been related as an essential structure for temporal integration of sensory information, the association of events temporally separated and the regulating of selection, representation and interpretation of multimodal stimuli, the effects of pre-limbic medial PFC reversible inactivation in contextual memories acquisition that depend on processing time between discontinuous stimuli will be investigated. For a better understanding of the neurobiological mechanisms involved and the interaction of pre-limbic medial PFC with other structures that have been implicated in the associative learning, the effect of reversible inactivation in the induction of synaptic plasticity in the hippocampus and amygdala will also be investigated.