The authors regret that the below mentioned were missed in the published article. , it came to our attention that when calculating variance in effect sizes, we had inadvertently used a formula designed for independent samples while our study only examined within subject designs. Consequently, we have re-analyzed the data using an equation for paired samples. , Vd = [1/n + (d2/2n)] ∗ [2(1 − r)], where Vd is variance in the effect size as measured by Cohen's d, n is the number of pairs and r is the estimated correlation between pairs. We estimated r as being 0.85 based on literature examining the test re-test reliability coefficients between performances on tests similar to those used in the studies examined [3–6]. The re-analyzed pooled effect size as measured by Hedges’ g and the 95% confidence intervals (CI) of g (g = −0.26, SE = 0.06, CI −0.37 to −0.13, p <.001) only differ marginally from those presented in the article (g = −0.27, SE = 0.12, CI −0.49 to −0.04, p <.05). Similarly, the re-analyzed measures of heterogeneity (Q(10) = 10.45, p >.10, T2 < 0.01, I2 = 0.04) also do not differ much from those presented in the article (Q(10) = 2.78, p >.10. T2 < 0.01, I2 < 0.01). The authors apologize for this mistake but the re-analysis does not affect the scientific discussion and conclusions of the article in any way.