Transcranial magnetic stimulation over right intraparietal sulcus improves selective attention for feature discriminating

Previous studies have confirmed the coordinated control of attentional processes by the frontal and parietal lobes. However, the function of the intraparietal sulcus (IPS) in the attention system remains unclear. In this study, we measured transcranial magnetic stimulation (TMS)-evoked event-related potentials (ERPs) to determine the extent to which the right intraparietal sulcus (rIPS) is involved in attentional processing. We hypothesized that TMS potentiates the activation of the rIPS during attentional processing. We enrolled 26 healthy participants who received single-pulse real and sham TMS at the rIPS while performing a dual-feature delayed matching task with sequential pairs of visual stimuli (S1 followed by S2). Participants were asked to discriminate whether the relevant feature of S2 was identical to S1 while ignoring the irrelevant feature. The results showed a shorter response time for real TMS to the rIPS compared to sham TMS in the color task. N270 amplitudes decreased during selective attentional processing. Single-pulse TMS to the rIPS decreases the amplitude of the N270, improving selective attention and enhancing task performance. Our results show that TMS can activate the IPS to facilitate attentional processing for feature discrimination.