“…This resulted in 29 studies in the analysis, using the following task types: (a) n-back tasks, (b) item recognition tasks (e.g., Sternberg tasks), (c) complex CPT tasks, (d) a heterogeneous group of delayed match-to-sample tasks, and (e) a single mental arithmetic task (Hugdahl et al, 2004). One doctoral dissertation (Mendrek, 2000) reported data for two independent samples of patient and control participants and so was included as two separate studies, resulting in a total of 30 studies in the…”