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Abstract: Using measurements of event-related potentials (ERPs) during a facial recognition task, we aimed to investigate the facial inversion effect and the role of time-based attention in processing upright and inverted faces. We presented upright and inverted faces at the T2 (target 2) position using a rapid serial visual presentation paradigm. Our results indicate that the N170 component shows the usual face inversion effect (FIE), in which inverted faces elicit larger N170 amplitudes and a longer elicit N170 latency. We also found that upright faces elicit larger P1 amplitudes than inverted faces over the left hemisphere. This study indicates that the N170 and P3, but not the P1, components are modulated by time-based attention. In addition, we found that the N170 amplitude was modulated by an attentional blink (AB) based on behavioral data. These results suggest that the disruption of facial configuration processing caused by inverted faces is relatively independent of attentional resources. [Copyright &y& Elsevier]

Abstract: The attentional blink (AB) refers to an impairment in the report of a second target (T2) if it closely follows the presentation of a first target (T1) in a rapid serial visual presentation (RSVP), when both targets must be reported. In the present study, a modified AB paradigm was used in which targets could appear in any of four simultaneous RSVP streams, one in each quadrant of the visual field. In half of the trials, T1 and T2 were displayed in the same visual hemifield (either left or right) and, in the other half, T1 and T2 were displayed in different visual hemifields. Using this paradigm with both neurologically intact individuals and a split-brain patient, we sought to investigate (1) possible hemispheric asymmetries in attentional processes, and (2) whether the AB would be reduced when targets are displayed in different visual hemifields. A comparable AB was found for both neurologically intact individuals and the split-brain patient, with no significant variations due to whether targets were displayed in the same or in different hemifields. A left hemisphere advantage in the processing of same and different hemifield targets was observed only in the split-brain patient. [Copyright &y& Elsevier]

Abstract: An attentional blink (AB) paradigm was used to directly compare semantic and repetition priming for reported words versus missed words. Three target words (T1, T2, T3) were embedded in a rapidly presented stream of non-word distractors for report at the end of each trial. Whereas T1 was not related to either T2 or T3, T2 and T3 could be unrelated words, semantically related words, or identical. Semantic and repetition priming effects were evident in both behavioral and electrophysiological measures on T3, whether T2 was accurately reported or ‘blinked’. These results suggest that semantic and repetition priming effects, under rapid serial visual presentation conditions, are modulated by at least partially overlapping neural mechanisms. [Copyright &y& Elsevier]

• Effects of vagus nerve stimulation on noradrenergic activity is tested in three studies. • Vagus nerve stimulation does not affect attentional control in high trait worriers. • Vagus nerve stimulation does not affect noradrenergically driven pupil dilation. Transcutaneous stimulation of the auricular branch of the vagus nerve (tVNS) has been proposed as a treatment for a spectrum of physical and psychological disorders. One of the proposed working mechanisms of tVNS is a modulatory effect on the locus coeruleus – noradrenaline (LC-NA) network. We tested this hypothesis in humans in a series of three studies: one focusing on high trait worriers, and two in healthy populations. In all three studies, we tested whether tVNS increases resting pupil diameter – as an index of LC-NA network activity. Additionally, we tested whether tVNS affects task performance and task-related pupil dilation during an Attentional Blink task. We found no evidence that tVNS increases pupil diameter or task-related pupil dilation in any of the tasks. No consistent effects of tVNS on performance on the attentional blink task were found. Overall, the results of these studies indicate that tVNS does not affect these behavioral and physiological indices of noradrenergic activity. [ABSTRACT FROM AUTHOR]