FIGURE 3.

Spatial bias in perceptual line bisection (PSE during landmark task performance) over time (six blocks) in three experimental sessions varying in terms of the tES protocol used (experiment 1). tES was applied with a right parietal – left frontal montage for 10 min using either α-tACS, c-tDCS or sham tES during blocks 3–4 (B3–4, shaded area). (A) Overall group mean PSE values (19 participants, within-subject design) as a function of blocks (B1–6) and tES (line plots). During the second block of tES (block 4), α-tACS significantly differed from sham and c-tDCS. The asterisk indicates a significant difference between Sham and α-tACS (p < 0.05). (B) Performance split according to “rightward shifters” (upper main graph, 14/19 participants) and “leftward shifters” (lower inset, 5/19 participants) during α-tACS (as compared to sham in block 4). The pattern of results is consistent with α-tACS having shifted spatial bias rightward (reduced pseudoneglect) in the majority of participants. (C) Performance split according to “rightward shifters” (upper main graph, 12/19 participants) and “leftward shifters” (lower inset, 7/19 participants) during c-tDCS (as compared to sham in block 4). No effects of active stimulation (c-tDCS vs. sham) are discernible in this condition and population. The error bars represent 95% confidence interval corrected for a within subjects design (Cousineau, 2005).