Posterior parietal cortex (PPC) may contribute to visual selection by exerting top-down influences on visual processing. To seek direct evidence for this, we used 10 Hz repetitive transcranial magnetic stimulation (rTMS) over right or left PPC in nine healthy volunteers during a partial (selective) report task that allows quantitative assessment of top-down control and other parameters. Participants reported digits in a relevant color ("targets") but not those in an irrelevant color ("nontargets") from a brief masked display, in which a target could appear alone or together with an accompanying item (nontarget or target) in the same or opposite hemifield. Generally, a given target is identified better when presented with a nontarget than with another target, indicating top-down selection of task-relevant targets; this applied here with no rTMS or left PPC rTMS. However, rTMS over the right PPC changed the performance pattern. A left target no longer impeded report of a right target more strongly than did a left nontarget, whereas the greater impact of a right target than a right nontarget in disrupting report of a left target was increased. Formal analysis in terms of Bundesen's (1990) theory of visual attention indicated that right PPC rTMS diminished top-down control for the left hemifield while enhancing this for the right hemifield, particularly for bilateral two-item displays. These findings indicate a role for right PPC in top-down spatial selection, which applies even when the target is defined by a nonspatial property (here color).

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Intermittent theta burst stimulation (iTBS), a patterned repetitive transcranial magnetic stimulation, was applied over the posterior superior temporal sulcus (pSTS) or dorsolateral prefrontal cortex (DLPFC) to explore its impact in adults with autism spectrum disorder (ASD). Among 25 adults with ASD, 19 (mean age: 20.8 years) completed the randomized, sham-controlled, crossover trial. Every participant received iTBS over the bilateral DLPFC, bilateral pSTS and inion (as a sham control stimulation) in a randomized order with a 1-week interval. Neuropsychological functions were assessed using the Conners' Continuous Performance Test (CCPT) and the Wisconsin Card Sorting Test (WCST). Behavioral outcomes were measured using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and the Social Responsiveness Scale (SRS). In comparison to that in the sham stimulation, the reaction time in the CCPT significantly decreased following single DLPFC session (p = 0.04, effect size = 0.71) while there were no significant differences in the CCPT and WCST following single pSTS session. Besides, the results in behavioral outcomes were inconsistent and had discrepancy between reports of parents and patients. In conclusion, a single session of iTBS over the bilateral DLPFC may alter the neuropsychological function in adults with ASD. The impacts of multiple-sessions iTBS over the DLPFC or pSTS deserve further investigations.