Amnesia is a Deficit in Relational Memory

TLDR

Scene memory contains relational information that may be inaccessible to verbal report. Eye movements were tracked to indirectly assess scene memory. Controls exhibited a relational manipulation effect without explicit awareness, whereas amnesic patients failed to show this effect, indicating a core deficit in relational memory.

Abstract

Eye movements were monitored to assess memory for scenes indirectly (implicitly). Two eye movement—based memory phenomena were observed: (a) the repetition effect, a decrease in sampling of previously viewed scenes compared with new scenes, reflecting memory for those scenes, and (b) the relational manipulation effect, an increase in viewing of the regions where manipulations of relations among scene elements had occurred. In normal control subjects, the relational manipulation effect was expressed only in the absence of explicit awareness of the scene manipulations. Thus, memory representations of scenes contain information about relations among elements of the scenes, at least some of which is not accessible to verbal report. But amnesic patients with severe memory impairment failed to show the relational manipulation effect. Their failure to show any demonstrable memory for relations among the constituent elements of scenes suggests that amnesia involves a fundamental deficit in relational (declarative) memory processing.