Hyperstriatal Lesions in Pigeons Disrupt Recognition Memory at Long, but not at Short, Inter-Trial Intervals

Two series of experiments investigated short-term visual recognition memory in pigeons following lesions of the hyperstriatal complex; the first series used a choice technique, the second, a single-key go/no go technique. The results of the two series agreed, first, in finding impaired performance in hyperstriatal birds at long but not at short inter-trial intervals, and, second, in obtaining no evidence of differential rates of decay of traces in hyperstriatal and control subjects. A final experiment confirmed that the hyperstriatal birds were, as expected from previous work, impaired on reversals of colour and position discriminations. It is tentatively suggested that deficits following hyperstriatal damage in both recognition and reversal performance may be understood as being the consequence of an increased susceptibility to frustrating events in hyperstriatal subjects.