Item-Method Directed Forgetting Is (Usually) Impaired in Clinical Populations: A Meta-Analysis

The item-method directed forgetting paradigm is a common laboratory task used to measure memory control. While impaired memory control may contribute to the development and/or maintenance of a variety of psychological disorders, comparisons between clinical and nonclinical groups using this paradigm have been inconsistent-even within the same disorder. A systematic search for related articles utilizing clinical populations was conducted revealing 823 articles of which 36 met inclusion criteria. Raw mean differences were calculated and aggregated using Bayesian multilevel random-effects models. These models revealed a significant difference in the magnitude of directed forgetting between clinical and control populations, such that clinical populations (collapsing across all disorders or combining only the critical anxiety and depression clusters) exhibited a reduced directed forgetting effect. This difference tended to be larger in clinical (as opposed to clinical-analog) populations and in older samples. These results support the notion that item-method directed forgetting provides a suitable measure of memory control sensitive to real-world control deficits and further implies that memory control deficits may contribute to mental illness (although causality remains to be determined).