Short-term memory, inhibition, and attention in developmental stuttering: A meta-analysis

Abstract

Purpose: This study presents a meta-analytic review of differences in verbal short-term memory, inhibition, and attention between children who stutter (CWS) and children who do not stutter (CWNS). Method: Electronic databases and reference sections of articles were searched for candidate studies that examined verbal short-term memory, inhibition, and attention using behavioral and/or parent report measures. Twenty-nine studies met the eligibility criteria, which included, among other things, children between the ages of 3 and 18 years and the availability of quantitative data for effect size calculations. Data were extracted, coded, and analyzed, with the magnitude of the difference between the 2 groups of children being estimated using Hedge's g (Hedges & Olkin, 1985). Results: Based on the random-effects model (Hunter & Schmidt, 2004), findings revealed that CWS scored lower than CWNS on measures of nonword repetition (Hedges' g = −0.62), particularly at lengths of 2 and 3 syllables (Hedges' g = −0.62 and − 0.50, respectively), and forward span (Hedges' g = −0.40). Analyses further revealed that the parents of CWS rated their children as having weaker inhibition (Hedges' g = −0.44) and attentional focus/persistence (Hedges' g = −0.36) skills than the parents of CWNS, but there were no significant differences between CWS and CWNS in behavioral measures of inhibition and attention. Conclusion: The present findings were taken to suggest that cognitive processes are important variables associated with developmental stuttering.