Procedural learning is impaired in dyslexia: Evidence from a meta-analysis of serial reaction time studies

•A systematic review and meta-analysis was used to investigate whether procedural learning is impaired in dyslexia.•The review confirms dyslexia is associated with a procedural learning impairment.•Differences in study findings may reflect compensatory mechanisms associated with the declarative memory system. A number of studies have investigated procedural learning in dyslexia using serial reaction time (SRT) tasks. Overall, the results have been mixed, with evidence of both impaired and intact learning reported. We undertook a systematic search of studies that examined procedural learning using SRT tasks, and synthesized the data using meta-analysis. A total of 14 studies were identified, representing data from 314 individuals with dyslexia and 317 typically developing control participants. The results indicate that, on average, individuals with dyslexia have worse procedural learning abilities than controls, as indexed by sequence learning on the SRT task. The average weighted standardized mean difference (the effect size) was found to be 0.449 (CI95: .204, .693), and was significant (p