DRL-PERFORMANCE AND TIMING BEHAVIOR OF PIGEONS WITH ARCHISTRIATAL LESIONS

Pigeons with bilateral archistriatal lesions show on a DRL-10 sec schedule a positive shift in peak and range of distribution of long inter-response times (IRT) (interval of 2 sec or more). The distribution of shorter IRT's and the overall locomotor activity are not affected. Control lesions in the adjacent neostriatum have only negligible effects. The characteristic timing behavior on an FI-30 sec schedule is not interrupted either by archistriatal or by neostriatal lesions. The more efficient adaptation of pigeons with archistriatal lesions to the DRL-schedule is interpreted as a disinhibition of the error evaluating process caused by a deterioration of the reward sensitive limbic component, the archistriatum. © 1969.