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Abstract: Gaze direction is known to be an important factor in regulating social interaction. Recent evidence suggests that direct and averted gaze can signal the sender''s motivational tendencies of approach and avoidance, respectively. We aimed at determining whether seeing another person''s direct vs. averted gaze has an influence on the observer''s neural approach–avoidance responses. We also examined whether it would make a difference if the participants were looking at the face of a real person or a picture. Measurements of hemispheric asymmetry in the frontal electroencephalographic activity indicated that another person''s direct gaze elicited a relative left-sided frontal EEG activation (indicative of a tendency to approach), whereas averted gaze activated right-sided asymmetry (indicative of avoidance). Skin conductance responses were larger to faces than to control objects and to direct relative to averted gaze, indicating that faces, in general, and faces with direct gaze, in particular, elicited more intense autonomic activation and strength of the motivational tendencies than did control stimuli. Gaze direction also influenced subjective ratings of emotional arousal and valence. However, all these effects were observed only when participants were facing a real person, not when looking at a picture of a face. This finding was suggested to be due to the motivational responses to gaze direction being activated in the context of enhanced self-awareness by the presence of another person. The present results, thus, provide direct evidence that eye contact and gaze aversion between two persons influence the neural mechanisms regulating basic motivational–emotional responses and differentially activate the motivational approach–avoidance brain systems. [Copyright &y& Elsevier]

Abstract: Orienting of visual attention can be automatically triggered not only by illumination changes occurring in the visual periphery but also by centrally presented gaze and arrow cues. We investigated whether the automatic shifts of visuospatial attention triggered by centrally displayed gaze and arrow cues rely on the same neural systems. To this end we measured event-related potentials (ERPs) time-locked to the cue and target onsets while the participants (n =17) performed a spatial cuing task. In the task, the participants detected and responded to laterally presented targets preceded by centrally presented, non-predictive, gaze or arrow cues. Manual reaction times and target-triggered ERP data showed that both gaze and arrow cues automatically oriented attention and facilitated subsequent processing of target stimuli. However, the cue-triggered electrophysiological data indicated that the ERPs elicited by the gaze and arrow cues were different at lateral parietal and fronto-central electrode sites. Most notably, for the arrows, we found a typical early attention direction negativity (EDAN) effect occurring 220–260 ms after the cue onset. The ERPs were shifted in the negative direction when the arrows pointed to a direction which was contralateral to the recorded hemisphere as compared to arrows with ipsilateral direction. This effect was not observed for the gaze stimuli. These results provide further support for earlier behavioral and neuroimaging studies indicating that automatic orienting of attention by arrow cues and gaze cues are based on different neural mechanisms. [Copyright &y& Elsevier]

Abstract: Previous studies have shown differential event-related potentials (ERPs) to fearful and happy/neutral facial expressions. To investigate whether the brain systems underlying these ERP differences are sensitive to the intensity of fear and happiness, behavioral recognition accuracy and reaction times as well as ERPs were measured while observers categorized low-intensity (50%), prototypical (100%), and caricatured (150%) fearful and happy facial expressions. The speed and accuracy of emotion categorization improved with increasing levels of expression intensity, and 100% and 150% expressions were consistently classified as expressions of the intended emotions. Comparison of ERPs to 100% and 150% expressions revealed a differential pattern of ERPs to 100% and 150% fear expressions over occipital–temporal electrodes 190–290 ms post-stimulus (a negative shift in ERP activity for high-intensity fearful expressions). Similar ERP differences were not observed for 100% and 150% happy expressions, ruling out the possibility that the ERPs to high-intensity fear reflected a response to increased expression intensity per se. Together, these results suggest that differential electrocortical responses to fearful facial expressions over posterior electrodes are generated by a neural system that responds to the intensity of negative but not positive emotional expressions. [Copyright &y& Elsevier]

Functional abnormalities in emotion-related brain systems have been implicated in depression, and depressed patients may therefore attribute emotional valence to stimuli that are normally interpreted as emotionally neutral. The present study examined this hypothesis by comparing recognition of different facial expressions in patients with moderate to severe depression. Eighteen depressed patients and 18 matched healthy controls made a forced-choice response to briefly presented neutral, happy, and sad faces. Recognition accuracy and response time were measured. Twelve patients were retested after showing signs of symptom remission. Depressed patients and controls were equally accurate at recognizing happy and sad faces. Controls also recognized neutral faces as accurately as happy and sad faces, but depressed patients recognized neutral faces less accurately than either happy or sad faces. Depressed patients were also particularly slow to recognize neutral faces. The impairment in processing of neutral faces was still evident after symptom remission. Error analyses showed that depressed patients attributed not only sadness, but also happiness (in remission), to neutral faces. These results suggest that, unlike healthy subjects, depression-prone individuals do not seem to perceive neutral faces as unambiguous signals of emotional neutrality. [Copyright &y& Elsevier]

• After 5 months of age, infants begin to prioritize attention to fearful over other facial expressions. • Amygdala and related early-maturing subcortical network, is important for emergence of this attentional bias. • Left amygdala volume associates positively with the emerging perceptual vigilance for fearful faces during infancy. • possible link from the prenatally defined variability in the amygdala size to social traits After 5 months of age, infants begin to prioritize attention to fearful over other facial expressions. One key proposition is that amygdala and related early-maturing subcortical network, is important for emergence of this attentional bias – however, empirical data to support these assertions are lacking. In this prospective longitudinal study, we measured amygdala volumes from MR images in 65 healthy neonates at 2–5 weeks of gestation corrected age and attention disengagement from fearful vs. non-fearful facial expressions at 8 months with eye tracking. Overall, infants were less likely to disengage from fearful than happy/neutral faces, demonstrating an age-typical bias for fear. Left, but not right, amygdala volume (corrected for intracranial volume) was positively associated with the likelihood of disengaging attention from fearful faces to a salient lateral distractor (r =.302, p =.014). No association was observed with the disengagement from neutral or happy faces in equivalent conditions (r =.166 and.125, p =.186 and.320, respectively). These results are the first to link the amygdala volume with the emerging perceptual vigilance for fearful faces during infancy. They suggest a link from the prenatally defined variability in the amygdala size to early postnatal emotional and social traits. [ABSTRACT FROM AUTHOR]

TPH2, the rate-limiting enzyme in the synthesis of serotonin, has been connected to several psychiatric outcomes. Its allelic variant, rs4570625, has been found to relate to individual differences in cognitive and emotion regulation during infancy with T-carriers of rs4570625 showing a relatively heightened attention bias for fearful faces. A significant gene-environment interaction was also reported with the T-carriers of mothers with depressive symptoms showing the highest fear bias. We investigated these associations in a sample of 8-month old infants (N = 330), whose mothers were prescreened for low/high levels of prenatal depressive and/or anxiety symptoms. Attention disengagement from emotional faces (neutral, happy, fearful, and phase-scrambled control faces) to distractors was assessed with eye tracking and an overlap paradigm. Maternal depressive symptoms were assessed at several time points during pregnancy and postpartum. The mean levels of symptoms at six months postpartum and the trajectories of symptoms from early pregnancy until six months postpartum were used in the analyses (N = 274). No main effect of the rs4570625 genotype on attention disengagement was found. The difference in fear bias between the genotypes was significant but in an opposite direction compared to a previous study. The results regarding the interaction of the genotype and maternal depression were not in accordance with the previous studies. These results show inconsistencies in the effects of the rs4570625 genotype on attention biases in separate samples of infants from the same population with only slight differences in age. [ABSTRACT FROM AUTHOR]