Spatial Cueing Effects on Visual Perception

Subjects were removed from analysis if their asymptotic level of performance ( $s$ ) for at least one of their SOA/location conditions was three or more standard deviations lower than the mean across all conditions (12.5% subjects in total). Trials in which fixation deviated by more than a distance of $3{}^{\circ }$ from the fixation cross during target/flanker presentation were also removed from analysis ( $2.8\%$ of trials). Mean RT and critical spacing were analyzed with a repeated-measures analysis of variance with SOA (40 or 600 ms) and stimulus location (cue or opposite side) entered as within-subject factors. We additionally conducted a number of planned comparisons to assess the effects of the cue on RT and critical spacing. Specifically, for each SOA we defined the cueing effects as a pairwise difference between values when the stimulus appeared on the cue side and values when the stimulus appeared on the opposite side. We used two-tailed Student’s t tests to assess if the means of the cueing effects were significantly different than zero. Additionally, we computed Cohen’s $d$ effect sizes for the paired differences. For the correlation analyses, Pearson’s $r$ values were calculated and tested against the null hypothesis of a correlation coefficient value of zero.