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 is thought to contribute to the development and/or maintenance of a variety of psychological disorders, comparisons between clinical and non-clinical 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 multi-level random effects models. These models revealed a significant difference in the magnitude of directed forgetting between clinical and control populations such that clinical populations 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.