Implicit and explicit memory bias in a sample of tertiary students screening low, medium and high in bulimic psychopathology: are their memories word specific?

Abstract

Stroop task research findings have suggested that eating disorder patients may have similar cognitive structures to those of depressed and anxious patients. Specifically, that they have disorder focussed cognitive schemas that result in implicit or, explicit memory biases for words that are emotionally salient to them. Five previous studies have investigated implicit and explicit memory biases in anorexia nervosa patients. However, to date, no study has investigated whether sub-clinical bulimia nervosa samples demonstrate explicit or implicit memory biases for eating disorder related words (EDRW) in relation to non eating disorder related words (NEDRW). This study aimed to investigate such an effect. Sixty-five subjects completed the Bulimia Test Revised (BULIT-R) and on the basis of their scores on this measure they were grouped into either low, medium, or high bulimia nervosa symptom groups. A procedure similar to MacLeod and Mclaughlins (1995) study on implicit and explicit memory bias in anxiety patients was employed utilising both a tachistoscopic identification task and a recognition task respectively. A MANOVA revealed no significant differences between the three subject groups in terms of their implicit and explicit processing of both new and old (i.e. previously seen words), EDRW and NEDRW. Surprisingly, all three groups remembered more EDRW than NEDRW on both the implicit and explicit memory tests. Furthermore, although an explicit memory bias for previously encoded words was observed no similar implicit memory bias was observed. As a result of an overall lack of implicit primming consequential interpretations of significant implicit test findings are problematic. Findings are discussed in light of the current cultural climate and the sample population employed.