Psychological Study of the Amnesic Syndrome: Effects of Interference on Recall

Abstract

The effect of a visual interference task on the ability to memorize orally presented serial digits was tested in a sample of 22 chronic Korsakoff patients, and in a control group consisting primarily of relatives of hospitalized psychiatric patients. The general performance of the controls was significantly better than that of the patients. There was no significant sex differences in either group. Neither practice nor fatigue seemed to play a part in affecting the Korsakoff patients’ performance; however, the control group scored more errors in the latter half of the experiment, presumably due to lessening of their concentration. In neither group was there a significant increase in errors as recall times were increased over the interval 40 to 120 seconds. Likewise, increased rehearsal time prior to interference did not improve performance in either group. In both the Korsakoff and control groups the interfering task and a detrimental effect on the recall of the digits. The Korsakoff patients, but not the controls, had a significantly poorer performance with early interference. An analysis of the types of errors of digit recall revealed that a significant amount of perseveration occurred in both groups.