Recognition memory in mentally retarded persons

The continuous recognition memory of retarded and normal subjects was assessed. The stimuli were magazine pictures, arranged so that lags of up to 250 pictures occured. The overall performance of the retarded subjects was poorer, in terms of hit rate or d′. However, the differences were present at 0 lag and the slopes of the forgetting curves were similar in both groups. It was concluded that differences between these subjects were due to a perception related process and not to memory.