[Distribution of behaviorally specialized neurons and expression of the c-fos transcription factor in the rat...

In order to investigate the relation between the immediate early gene induction in neurons and neuronal specialization in respect to functional systems of newly formed behavior, the neuronal expression of Fos transcription factor in rat brain was studied in animals of learning group and home cage control group. Animals of the learning group acquired a new behavior of pressing a pedal. Fos-positive neurons were counted in the retrosplenial area of cingulate cortex and anterolateral area of motor cortex, i.e., the two brain regions that differ in the number of neurons showing specific activity during this behavior. In the home cage control animals the number of Fos-positive neurons was low and no difference was found between the two brain regions. In the animals of the learning group the number of Fos-positive neurons was significantly higher in the cingulate cortex characterized by the greater number of neurons specialized in relation to the system of new behavior. These findings suggest that the c-Fox expression can indicate the processes of neuronal specialization.