The effect of self-initiated weight-loss dieting on working memory: the role of preoccupying cognitions

This study investigated the effects of weight loss dieting on the components of working memory and the extent to which these effects were mediated by preoccupying cognitions concerning food, diet and body shape. A dual task paradigm was used in which dieters (n=20) and non-dieters (n=20) completed mental arithmetic problems concurrently with suppression tasks designed to engage the central executive, phonological loop, and visuo-spatial sketchpad components of working memory. In addition, tasks reflecting the articulatory control process and phonological store sub-components of the phonological loop were also completed. Results showed that dieters performed more poorly on measures of the central executive and the phonological loop compared with non-dieters. Dieters reported higher levels of preoccupying cognitions which mediated the relationship between dieting status and functioning of the central executive and phonological loop, and the phonological store in particular.