Contextual Updating in Attentional Orienting Relies on the Right Temporoparietal Junction: Evidence From rTMS

The right temporoparietal junction (rTPJ) has been associated with multiple cognitive functions. Particularly, its involvement in attentional processes has been proposed, representing a key node in shifting and reorienting visuospatial attention toward unexpected stimuli. However, more recent evidence has demonstrated a more postperceptual function, suggesting a crucial engagement of rTPJ in contextual updating mechanisms. Therefore, considering the lack of consensus, the aim of the current study was to elucidate rTPJ contribution to attentional processes by applying repetitive transcranial magnetic stimulation (rTMS) throughout the administration of a location-cueing paradigm. Importantly, the latter was built in order to permit the disentangling of two critical attentional mechanisms: visuospatial reorienting and contextual updating. Data were collected from young healthy participants performing a discrimination task in a Posner-like paradigm while online rTMS interfered with rTPJ activity starting from 250 ms after the target onset (three pulses at 20 Hz per trial). Comparing behavioral outcomes of the active rTMS condition with a Sham condition (i.e., no stimulation), allowed us to directly observe rTMS effects on the neural processes at hand. Our findings showed an intact advantage of being attentionally focused on the attended location along with the cost of rearranging attentional resources to the unattended location in both rTMS and Sham condition, thus supporting that rTPJ should not be involved in triggering the reorienting of attention toward unexpected locations. Rather, rTMS selectively affected participants' ability to update the predictive attentional context, letting us conclude that rTPJ could be engaged in postperceptual and contextual updating mechanisms.