The effects of divided attention during encoding and retrieval on amnesic patients' memory performance

This study examined the effect of divided attention during encoding or retr ieval on primary (recall) or secondary (button-pressing) task performance b y amnesic patients and control subjects. Experiment 1 demonstrated that con trol subjects' recall was affected by divided attention during encoding but not during retrieval, while the amnesic patients' recall remained at the s ame low level for all conditions. Both groups showed a reduction in rate of button-pressing during encoding relative to their baseline levels and a fu rther reduction during the retrieval interval. In Experiment 2, five learni ng trials, instead of just one, were presented. This acted to increase all subjects' recall and also had the effect of producing superior recall follo wing free encoding relative to encoding during divided attention for the am nesic patients as well as for the control subjects. Button-pressing perform ance during the encoding interval increased to baseline for both groups dur ing the five presentation trials, but there was no increase in the rate of button-pressing during the retrieval interval. Amnesic patients' normal att ention to the primary task during encoding and retrieval was felt to have s everal implications for future neuroimaging tasks with these patients.