A., Perry, Rubinsten Orly., Peled Leehe., and Shamay-Tsoory S.G.Don't stand so close to me: A behavioral and ERP study of preferred interpersonal distance.” NeuroImage 83 (2013): 761 - 769. Publisher's VersionAbstract

The space between people, or interpersonal distance, creates and defines the dynamics of social interactions. Given that invasion of one's interpersonal space may trigger threat and anxiety, a critical question is if high vulnerability to social anxiety (SA) is associated with avoidance and attentional biases when anticipating invasion to one's interpersonal space. Therefore, the current study sought to examine the behavioral mechanisms, time course and neural correlates underlying the threat of interpersonal distance invasion with a focus on different SA levels, using both a behavioral and an ERP experiment. Preferred interpersonal distance was assessed using a paradigm that involves responding to different virtual protagonists (friend or stranger) approaching the participant by indicating where one would like the protagonist to stop. In addition, participants' level of social anxiety was measured. The behavioral experiment indicated that levels of SA predicted one's preferred interp

A., Perry, Aviezer H., Goldstein P., Palgi S., Klein E., and Shamay-Tsoory S.G.Face or body? Oxytocin improves perception of emotions from facial expressions in incongruent emotional body context.” Psychoneuroendocrinology 38, no. 11 (2013): 2820-2825. Publisher's VersionAbstract

The neuropeptide oxytocin (OT) has been repeatedly reported to play an essential role in the regulation of social cognition in humans in general, and specifically in enhancing the recognition of emotions from facial expressions. The later was assessed in different paradigms that rely primarily on isolated and decontextualized emotional faces. However, recent evidence has indicated that the perception of basic facial expressions is not context invariant and can be categorically altered by context, especially body context, at early perceptual levels. Body context has a strong effect on our perception of emotional expressions, especially when the actual target face and the contextually expected face are perceptually similar. To examine whether and how OT affects emotion recognition, we investigated the role of OT in categorizing facial expressions in incongruent body contexts. Our results show that in the combined process of deciphering emotions from facial expressions and from context,

H., Aviezer, Hassin R., Perry A., Dudarev V., and Bentin S.The right place at the right time: Priming facial expressions with emotional face components in developmental visual agnosia.” Neuropsychologia 50, no. 5 (2012): 949 - 957. Publisher's VersionAbstract

The current study examined the nature of deficits in emotion recognition from facial expressions in case LG, an individual with a rare form of developmental visual agnosia (DVA). LG presents with profoundly impaired recognition of facial expressions, yet the underlying nature of his deficit remains unknown. During typical face processing, normal sighted individuals extract information about expressed emotions from face regions with activity diagnostic for specific emotion categories. Given LG's impairment, we sought to shed light on his emotion perception by examining if priming facial expressions with diagnostic emotional face components would facilitate his recognition of the emotion expressed by the face. LG and control participants matched isolated face components with components appearing in a subsequently presented full-face and then categorized the face's emotion. Critically, the matched components were from regions which were diagnostic or non-diagnostic of the emotion portray

A., Perry, Stein L., and Bentin S.Motor and attentional mechanisms involved in social interaction—Evidence from mu and alpha EEG suppression.” NeuroImage 58, no. 3 (2011): 895 - 904. Publisher's VersionAbstract

Mu rhythms are EEG oscillations in the 8–13Hz recorded at sites located roughly over the sensory-motor cortex. There is reliable evidence that the amplitude of mu rhythms is reduced when the participant performs a motor act (mu suppression). Recent studies found mu suppression not only in response to actual movements but also while the participant observes actions executed by someone else. This finding putatively associates the mu suppression to the activity of a mirror neurons system which, in humans, has been suggested to contribute to social skills. In the present study we explored the effects of different levels of social interaction on mu suppression. Participants observed dynamic displays of hand gestures performing actions used in the Rock–Scissors–Paper game. In different blocks, participants passively viewed identical video clips with no game context and in the context of a game, or while being actually engaged in the game either by imagining actions or by actual playing. As

A., Perry, and Bentin S.Does focusing on hand-grasping intentions modulate electroencephalogram mu and alpha suppressions?.” Neuroreport 21, no. 16 (2010): 1050 - 1054. Publisher's VersionAbstract

Understanding the intentions of others presumably involves a human analog of the mirror neuron system. A putative marker of such mirror activity is the suppression of electroencephalographic oscillations in the 8-12 Hz range, which, when recorded over somatosensory areas, is associated with motor activity and labeled mu rhythms. We investigated whether mu-suppression can be modulated by attention to another person's intention as expressed by her hand movement toward an object and whether this suppression is distinguished from the suppression of alpha waves that oscillate in the same frequency range and are modulated by attention and cognitive load. Both mu and alpha suppressions were modulated by task difficulty, and not distinctively by intention, reflecting the recruitment of resources needed for task performance. NeuroReport 21:1050-1054 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

A., Perry, Troje N.F., and Bentin S.Exploring motor system contributions to the perception of social information: Evidence from EEG activity in the mu/alpha frequency range.” Social Neuroscience 5, no. 3 (2010): 272 - 284. Publisher's VersionAbstract

Putative contributions of a human mirror neuron system (hMNS) to the perception of social information have been assessed by measuring the suppression of EEG oscillations in the mu/alpha (8-12 Hz), beta (15-25 Hz) and low-gamma (25-25 Hz) ranges while participants processed social information revealed by point-light displays of human motion. Identical dynamic displays were presented and participants were instructed to distinguish the intention, the emotion, or the gender of a moving image of a person, while they performed an adapted odd-ball task. Relative to a baseline presenting a nonbiological but meaningful motion display, all three biological motion conditions reduced the EEG amplitude in the mu/alpha and beta ranges, but not in the low-gamma range. Suppression was larger in the intention than in the emotion and gender conditions, with no difference between the latter two. Moreover, the suppression in the intention condition was negatively correlated with an accepted measure of em

A., Perry, Bentin S., Shalev I., Israel S., Uzefovsky F., Bar-On D., and Ebstein R.Intranasal oxytocin modulates EEG mu/alpha and beta rhythms during perception of biological motion.” Psychoneuroendocrinology 35 (2010): 1446 - 1453. Publisher's VersionAbstract

Oxytocin (OT) plays a determining role in social and pair bonding in many vertebrates and increasing evidence suggests it is a social hormone also in humans. Indeed, intranasal administration of OT modulates several social cognitive processes in humans. Electrophysiological studies in humans associated the suppression of EEG in the mu/alpha and beta bands with perception of biological motion and social stimuli. It has been suggested that mu and beta suppression over sensory-motor regions reflects a resonance system in the human brain analogous to mirror neurons in the monkey. We therefore hypothesized that OT, a social hormone, would enhance this suppression, hence, for the first time, link the action of this neuropeptide with a human correlate of mirror neuron activity. Twenty-four students were administered 24IU of OT or placebo intranasally in a robust, double-blind within-subject design. 45min later participants were shown a point-light display of continuous biological motion of a

A., Perry, Bentin S., Ben-Ami Bartal I., Lamm C., and Decety J.“Feeling” the pain of those who are different from us: Modulation of EEG in the mu/alpha range.” Cognitive, Affective and Behavioral Neuroscience 10 (2010): 493-504. Publisher's VersionAbstract

We explored how apparently painful stimuli and the ability to identify with the person on whom the pain is inflicted modulate EEG suppression in the mu/alpha range (8-12 Hz). In a 2 × 2 design, we presented pictures of hands either experiencing needle pricks or being touched by a Q-tip. In the dissimilar-other condition, the hand was assigned to a patient suffering from a neurological disease in which Q-tips inflicted pain, whereas needle pricks did not. In the similar-other condition, the hand was assigned to a patient who responded to stimulation in the same way as the healthy participant. Participants [...]

A., Perry, and Bentin S.Mirror activity in the human brain while observing hand movements: Equivalence between EEG desynchronization in the µ-range and fMRI.” Brain Research 1282 (2009): 126 - 132. Publisher's VersionAbstract

Mu (?) rhythms are EEG oscillations between 8–13 Hz distinguished from alpha by having more anterior distribution and being desynchronized by motor rather than visual activity. Evidence accumulating during the last decade suggests that the desynchronization of ? rhythms (? suppression) might be also a manifestation of a human Mirror Neuron System (MNS). To further explore this hypothesis we used a paradigm that, in a previous fMRI study, successfully activated this putative MNS in humans. Our direct goal was to provide further support for a link between modulation of ? rhythms and the MNS, by finding parallels between the reported patterns of fMRI activations and patterns of ? suppression. The EEG power in the ? range has been recorded while participants passively observed either a left or a right hand, reaching to and grasping objects, and compared it with that recorded while participants observed the movement of a ball, and while observing static grasping scenes or still objects. Mi

S., Gilaie-Dotan, Perry A., Bonneh Y., Malach R., and Bentin S.Seeing with Profoundly Deactivated Mid-level Visual Areas: Non-hierarchical Functioning in the Human Visual Cortex.” Cerebral Cortex 19, no. 7 (2009): 1687-1703. Publisher's VersionAbstract

A fundamental concept in visual processing is that activity in high-order object-category distinctive regions (e.g., lateral occipital complex, fusiform face area, middle temporal+) is dependent on bottom-up flow of activity in earlier retinotopic areas (V2, V3, V4) whose main input originates from primary visual cortex (V1). Thus, activity in down stream areas should reflect lower-level inputs. Here we qualify this notion reporting case LG, a rare case of developmental object agnosia and prosopagnosia. In this person, V1 was robustly activated by visual stimuli, yet intermediate areas (V2–V4) were strongly deactivated. Despite this intermediate deactivation, activity in down stream visual areas [...]