No abstract

Social-evaluative threat (SET) – a situation in which one could be negatively evaluated by others – elicits profound (psycho)physiological reactivity which, if chronically present and not adaptively regulated, has deleterious effects on mental and physical health. Decreased self-awareness and increased other-awareness are understood to be an adaptive response to SET. Attentional deployment – the process of selectively attending to certain aspects of emotional stimuli to modulate emotional reactivity – is supported by fronto-parietal and fronto-limbic networks, with the dorsolateral prefrontal cortex being a central hub. The primary aim of the current study was to investigate the effects of active (versus sham) prefrontal transcranial direct current stimulation (tDCS) on self and other-attentional deployment during the exposure to a SET context. Seventy-four female participants received active or sham tDCS and were subsequently exposed to a rigged social feedback paradigm. In this paradigm a series of social evaluations were presented together with a photograph of the supposed evaluator and a self- photograph of the participant, while gaze behavior (time to first fixation, total fixation time) and skin conductance responses (SCRs; a marker of emotional reactivity) were measured. For half of the evaluations, participants could anticipate the valence (negative or positive) of the evaluation a priori. Analyses showed that participants receiving active tDCS were (a) slower to fixate on their self-photograph, (b) spent less time fixating on their self-photograph, and (c) spent more time fixating on the evaluator photograph. During unanticipated evaluations, active tDCS was associated with less time spent fixating on the evaluation. Furthermore, among those receiving active tDCS, SCRs were attenuated as a function of slower times to fixate on the self-photograph. Taken together, these results suggest that in a context of SET, prefrontal tDCS decreases self-attention while increasing other-attention, and that attenuated self-referential attention specifically may be a neurocognitive mechanism through which tDCS reduces emotional reactivity. Moreover, the results suggest that tDCS reduces vigilance toward stimuli that possibly convey threatening information, corroborating past research in this area.

English-speaking autistic children use the hesitation marker “um” less often than non-autistic children while they use “uh” at a similar rate. It is unclear why this is the case. We examined hesitation marker usage of Dutch-speaking autistic and non-autistic preschoolers with the aim to 1) make a crosslinguistic comparison of hesitation marker usage and 2) examine two hypotheses regarding the underlying linguistic mechanisms of hesitation markers: the symptom hypothesis and the signal hypothesis. We replicated group differences in “um” usage and showed significant effects of age and biological sex in the selection of hesitation marker (“uh” versus “um”). We found that “uh” usage is correlated with structural language abilities while “um” is not. “Um” may be related to pragmatic language abilities, which were not examined here. The findings support the notion that hesitation markers are not involuntary utterances but deliberate language features, which is in line with the signal hypothesis.