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Faces and bodies provide critical cues for social interaction and communication. Their structural encoding depends on configural processing, as suggested by the detrimental effect of stimulus inversion for both faces (i.e., face inversion effect - FIE) and bodies (body inversion effect - BIE). An occipito-temporal negative event-related potential (ERP) component peaking around 170 ms after stimulus onset (N170) is consistently elicited by human faces and bodies and is affected by the inversion of these stimuli. Albeit it is known that emotional expressions can boost structural encoding (resulting in larger N170 components for emotional than for neutral faces), little is known about body emotional expressions. Thus, the current study investigated the effects of different emotional expressions on structural encoding in combination with FIE and BIE. Three ERP components (P1, N170, P2) were recorded using a 128-channel electroencephalogram (EEG) when participants were presented with (upright and inverted) faces and bodies conveying four possible emotions (happiness, sadness, anger, fear) or no emotion (neutral). Results demonstrated that inversion and emotional expressions independently affected the Accuracy and amplitude of all ERP components (P1, N170, P2). In particular, faces showed specific effects of emotional expressions during the structural encoding stage (N170), while P2 amplitude (representing top-down conceptualisation) was modified by emotional body perception. Moreover, the task performed by participants (i.e., implicit vs. explicit processing of emotional information) differently influenced Accuracy and ERP components. These results support integrated theories of visual perception, thus speaking in favour of the functional independence of the two neurocognitive pathways (one for structural encoding and one for emotional expression analysis) involved in social stimuli processing. Results are discussed highlighting the neurocognitive and computational advan

Viaggiare in ambienti sconosciuti è un'abilità essenziale. Durante la navigazione, siamo esposti a una grande quantità di informazioni, ma alcuni stimoli possono essere più rilevanti di altri. Mentre esiste una comprensione consolidata dei meccanismi alla base delle capacità di orientamento e un ampio consenso sull'effetto dell'elaborazione delle emozioni facciali sulla maggior parte dei processi cognitivi, poco si sa sull'interazione tra l'elaborazione delle emozioni altrui e le abilità di navigazione spaziale. La presente ricerca consiste in cinque esperimenti con circa 1.000 partecipanti per indagare come l'elaborazione delle emozioni negative altrui influenzi il wayfinding, i domini di navigazione spaziale e le abilità visuospaziali. In tutti gli esperimenti sono state prese in considerazione le differenze di genere. Nell'Esperimento 1, i partecipanti hanno navigato due volte in tre ambienti virtuali. La prima volta dovevano trovare un oggetto e la seconda dovevano ricordare il percorso per raggiungerlo. Tra le due fasi, i partecipanti hanno eseguito un compito di categorizzazione di genere di volti con espressioni neutre, paurose o arrabbiate. I risultati hanno mostrato che l'esposizione a facce paurose, ma non a facce arrabbiate o neutre, comprometteva le prestazioni di navigazione dei maschi, mentre le femmine non ne erano influenzate. Negli esperimenti 2 e 3 abbiamo esteso questa ricerca a stimoli emotivi diversi (cioè corpi o contesti) e non abbiamo riscontrato un impatto significativo sulla navigazione. Nell'Esperimento 4 abbiamo esplorato ulteriormente il modo in cui le emozioni negative del volto influenzano i domini di navigazione con sei compiti, dimostrando che l'elaborazione di volti spaventati (e in misura minore di volti arrabbiati) comprometteva le prestazioni dei maschi e migliorava quelle delle femmine, ma solo nei compiti che coinvolgevano le strategie di localizzazione e la conoscenza del percorso. L'esperimento 5 ha esteso la ricerca, Travelling unfamiliar environments is an essential ability. When navigating, we are exposed to a vast amount of information, but some cues might be more relevant than others. While there is a well-established understanding of mechanisms underlying orientational skills and a wide consensus on the effect of facial emotional processing on most cognitive processes, little is known about the interplay between processing others’ emotions and spatial navigation abilities. The present research consists of five experiments with approximately 1,000 participants to investigate how processing other’s negative emotions influences wayfinding, spatial navigation domains, and visuospatial skills. Gender differences were considered in all experiments. In Experiment 1, participants navigated three virtual environments twice. The first time was to find an object, and the second time was to recall the path to reach it. Between the two phases, participants performed a gender categorisation task of faces showing neutral, fearful, or angry expressions. Results showed that exposure to fearful faces, but not angry or neutral faces, impaired males' navigation performance, whereas females were unaffected. In Experiments 2 and 3 we extended this research to different emotional stimuli (i.e. bodies or contexts) and found no significant impact on wayfinding. In Experiment 4, we further explored how facial negative emotions affect navigation domains with six tasks, showing that processing fearful faces (and to a lesser extent angry faces) impaired males' and enhanced females' performance, but only in tasks involving location strategies and path survey knowledge. Experiment 5 extended the research to visuospatial skills, which are essential for navigation and face processing. The study evaluated whether processing negative emotions during a visuospatial task (Delayed Non-Match to Sample Task, DNMS) affects performance on a subsequent visuospatial task (Backward Corsi Block Tapping Task, CBT). The

Finding one’s way in unfamiliar environments is an essential ability. When navigating, we are overwhelmed with an enormous amount of information, and since we are relatively selective, some might be more relevant than others. Despite the well-established mechanisms underlying orientational skills, and the notable effects of facial emotions on most cognitive processes, little is known about emotions’ effects on spatial navigation. Hereby, this study aimed to explore how exposure to others’ negative emotional facial expressions affects wayfinding performances. Moreover, gender differences that characterise both processes were considered. Participants (N=54, 30 females) entered twice three realistic virtual environments created employing Virtual Reality: first, to encode a route to find an object (T1) and then to recall the learned path to reach the same object again (T2). In between the two phases, participants were asked to undergo a gender categorisation task and were exposed to sixty faces showing either neutral, fearful, or angry expressions. Results showed a significant interaction between emotions, time, and gender. In particular, the exposition to fearful faces, not angry ones, decreased males’ navigational performances, while females were unaffected by either emotional condition. Possible explanations for such gender and emotional dissimilarities are discussed. Keywords: Navigation, Faces, Emotions, Fear, Virtual Reality

I nostri tre studi ci forniscono un progresso nella conoscenza dei diversi meccanismi in gioco nella percezione della direzione dello sguardo, nel comportamento di seguire lo sguardo e nell'attenzione congiunta, sia a livello comportamentale che neurofisiologico. In particolare, la presente tesi porta prove dell'interazione e del corso temporale dei meccanismi cognitivi e neurali (processi bottom-up e top-down) che vengono reclutati quando si vede lo sguardo di altre persone. Questo equilibrio è possibilmente mantenuto al fine di prendere giustamente in considerazione o ignorare le informazioni provenienti dagli occhi di un'altra persona a seconda dei nostri obiettivi, dell'intenzione e del comportamento corrente., our three studies provide us with an advance in knowledge on the different mechanisms at play in the perception of gaze direction, gaze following behavior and joint attention, both at the behavioral and neurophysiological level. Specifically, the present thesis brings evidence of the interplay and time course of the cognitive and neural mechanisms (bottom-up and top-down processes) that are recruited when seeing other people’s gaze. This balance is possibly maintained in order to justifiably take into account or disregard information coming from another person’s eyes depending upon our goals, intention and current behavior.

In this study, we investigated whether the difficulties in body motion (BM) perception may led to deficit in emotion recognition in Autism spectrum disorder (ASD). To this aim, individuals with high-functioning ASD were asked to recognise fearful, happy, and neutral BM depicted as static images or dynamic point-light and full-light displays. Results showed slower response times in participants with ASD only in recognising dynamic stimuli, but no group differences in accuracy. This suggests that i) a deficit in action chaining mechanism in ASD may prevent the recognition of dynamic BM automatically and rapidly, ii) individuals with ASD and high cognitive resources can develop alternative—but equally successful—strategies to recognise emotional body expressions. Implications for treatment are discussed

Boxing athletes code the opponents’ intention to act in advance to plan and perform the most appropriate counterattack responses; in contrast, non-athletes respond with a defence action (Ottoboni, Russo, Tessari, 2015). We investigated whether such difference is limited at elaborating the most appropriate motor response or relies on different visual and attentional strategies during the early visual analysis of the opponent. We recorded saccades as indexes of visual attentional orienting during an implicit paradigm (i.e., a Simon-like task): nine experienced boxers and nine controls observed photographs of boxing attacks (jab and cross) or a neutral position (guard) and judged the colour of body parts either salient or not for elaborating the attack action (gloves vs. shorts, respectively) by shifting their gaze towards one of two lateral response boxes. Release reaction times (i.e., time between the start of the first saccade away from the fixation rectangle toward the response box) were faster toward the arm that seemed about to attack for the jab stance (the most dynamic one as implying motion) when judging the glove colour in both athletes and controls. No effect emerged when focusing on the shorts that provide irrelevant information for elaborating a defence or attack action. Therefore, athletes and controls seem to use the same visual strategies (saccadic movements) when analysing the opponent’s posture before acting. However, if expertise brings better motor response processing as previously found, the difference between athletes and non-athletes must lay in a later cognitive stage (other than the visual one) devoted to plane the most effective motor response.

Secondo il filosofo greco Aristotele "L'uomo è per natura un animale sociale". Dopo 2350 anni, oggi sappiamo che questa affermazione è solo parzialmente vera. Sebbene le evidenze sperimentali abbiano messo in luce una preferenza per gli stimoli e le interazioni sociali negli esseri umani, questa conclusione non sembra applicabile a tutti gli individui e contesti. L'elaborazione degli stimoli sociali può infatti essere influenzata da caratteristiche degli stimoli sociali e non sociali, presentati in competizione, nonché da caratteristiche inter-individuali. Tra quest'ultime, il Disturbo dello Spettro Autistico è sicuramente un esempio prototipico di atipicità nei comportamenti sociali e nella cognizione sociale. Il presente lavoro di tesi era rivolta a: i. indagare se gli stimoli sociali esercitano una priorità di elaborazione negli individui a sviluppo tipico (TD), anche quando presentati in competizione con altri stimoli non sociali fortemente rilevanti (denaro); ii. Indagare se e come gli individui con ASD rispondono a stimoli sociali vs non sociali rispetto agli individui TD, prendendo in esame un duplice livello di elaborazione, cognitivo e fisiologico; iii. Indagare se le differenze tra individui TD e ASD nell'elaborazione degli stimoli sociali e non sociali possano considerarsi l'espressione di un fenotipo familiare allargato; iv. Indagare la possibilità di modificare la salienza degli stimoli sociali negli individui con ASD attraverso una metodologia di apprendimento implicito ABMT (Attention Bias Modification Treatment). La presente tesi presenta tre implicazioni: teorica, metodologica e clinica. Per quanto riguarda le implicazioni teoriche, il presente lavoro supporta solo parzialmente l'affermazione di Aristotele. I risultati infatti hanno evidenziato chiaramente che, sebbene gli stimoli sociali abbiano solitamente un accesso prioritario agli step di elaborazione, la loro valenza può essere influenzata da una varietà di variabili come le differen, According to the Greek philosopher Aristotle “Man is by nature a social animal”. After 2350 years, we know that this statement is partially true. Although experimental evidence has reported a preference for social stimuli and social interactions in human beings, this conclusion does not apply to every individuals and contexts. Social stimuli processing can indeed be affected by stimuli and competitive non-social stimuli features as well as by inter-individual characteristics. Among the clinical conditions characterized by atypicality in social behaviours and social cognition (e.g., schizophrenia, personality disorders etc.), Autism Spectrum Disorder (ASD) is the most prototypical example. The present dissertation was aimed at: i. investigating whether social stimuli are prioritized by typically developed individuals (TD) even when they attentively compete with other relevant non-social stimuli (money); ii. Investigating whether and how individuals with ASD differently respond to social vs non-social stimuli compared to TD individuals, by considering both a cognitive and a physiological level of processing; iii. Investigating whether the differences between TD and ASD individuals in social vs nonsocial stimuli processing are the expression of a familiar phenotype; iv. Investigating whether it is possible to modify the salience of social stimuli in ASD individuals through an Attention Bias Modification Treatment (ABMT) methodology. The present dissertation is expected to provide three main implications: theoretical, methodological and clinical. As concerns the theoretical implications, the present work only partially supports Aristotle statement mentioned in the introduction. Indeed, the reported findings have clearly highlighted that, although social stimuli are usually prioritized, their valence may be affected by a variety of variables such as individual differences (e.g., autistic traits) or characteristics of the non-social stimuli presented in competition with t

Boxing athletes code the opponents' intention to act in advance to plan and perform the most appropriate counterattack responses; in contrast, non-athletes respond with a defence action (Ottoboni, Russo, Tessari, 2015). We investigated whether such difference is limited at elaborating the most appropriate motor response or relies on different visual and attentional strategies during the early visual analysis of the opponent. We recorded saccades as indexes of visual attentional orienting during an implicit paradigm (i.e., a Simon-like task): nine experienced boxers and nine controls observed photographs of boxing attacks (jab and cross) or a neutral position (guard) and judged the colour of body parts either salient or not for elaborating the attack action (gloves vs. shorts, respectively) by shifting their gaze towards one of two lateral response boxes. Release reaction times (i.e., time between the start of the first saccade away from the fixation rectangle toward the response box) were faster toward the arm that seemed about to attack for the jab stance (the most dynamic one as implying motion) when judging the glove colour in both athletes and controls. No effect emerged when focusing on the shorts that provide irrelevant information for elaborating a defence or attack action. Therefore, athletes and controls seem to use the same visual strategies (saccadic movements) when analysing the opponent's posture before acting. However, if expertise brings better motor response processing as previously found, the difference between athletes and non-athletes must lay in a later cognitive stage (other than the visual one) devoted to plane the most effective motor response.

According to the Polyvagal theory, the vagus nerve is the key phylogenetic substrate that supports efficient emotion recognition for promoting safety and survival. Previous studies showed that the vagus nerve affects people’s ability to recognize emotions based on eye regions and whole facial images, but not static bodies. The purpose of this study was to verify whether the previously suggested causal link between vagal activity and emotion recognition can be generalized to situations in which emotions must be inferred from images of whole moving bodies. We employed transcutaneous vagus nerve stimulation (tVNS), a noninvasive brain stimulation technique that stimulates the vagus nerve by a mild electrical stimulation to the auricular branch of the vagus, located in the anterior protuberance of the outer ear. In two sessions, participants received active or sham tVNS before and while performing three emotion recognition tasks, aimed at indexing their ability to recognize emotions from static or moving bodily expressions by actors. Active tVNS, compared to sham stimulation, enhanced the recognition of anger but reduced the ability to recognize sadness, regardless of the type of stimulus (static vs. moving). Convergent with the idea of hierarchical involvement of the vagus in establishing safety, as put forward by the Polyvagal theory, we argue that our findings may be explained by vagus-evoked differential adjustment strategies to emotional expressions. Taken together, our findings fit with an evolutionary perspective on the vagus nerve and its involvement in emotion recognition for the benefit of survival.

The gaze cueing effect involves the rapid orientation of attention to follow the gaze direction of another person. Previous studies reported reciprocal influences between social variables and the gaze cueing effect, with modulation of gaze cueing by social features of face stimuli and modulation of the observer’s social judgements from the validity of the gaze cues themselves. However, it remains unclear which social dimensions can affect—and be affected by—gaze cues. We used computer-averaged prototype face-like images with high and low levels of perceived trustworthiness and dominance to investigate the impact of these two fundamental social impression dimensions on the gaze cueing effect. Moreover, by varying the proportions of valid and invalid gaze cues across three experiments, we assessed whether gaze cueing influences observers’ impressions of dominance and trustworthiness through incidental learning. Bayesian statistical analyses provided clear evidence that the gaze cueing effect was not modulated by facial social trait impressions (Experiments 1–3). However, there was uncertain evidence of incidental learning of social evaluations following the gaze cueing task. A decrease in perceived trustworthiness for non-cooperative low dominance faces (Experiment 2) and an increase in dominance ratings for faces whose gaze behaviour contradicted expectations (Experiment 3) appeared, but further research is needed to clarify these effects. Thus, this study confirms that attentional shifts triggered by gaze direction involve a robust and relatively automatic process, which could nonetheless influence social impressions depending on perceived traits and the gaze behaviour of faces providing the cues.

The recognition of emotional body movement (BM) is impaired in individuals with Autistic Spectrum Disorder ASD, yet it is not clear whether the difficulty is related to the encoding of body motion, emotions, or both. Besides, BM recognition has been traditionally studied using point-light displays stimuli (PLDs) and is still underexplored in individuals with ASD and intellectual disability (ID). In the present study, we investigated the recognition of happy, fearful, and neutral BM in children with ASD with and without ID. In a non-verbal recognition task, participants were asked to recognize pure-body-motion and visible-body-form stimuli (by means of point-light displays-PLDs and full-light displays-FLDs, respectively). We found that the children with ASD were less accurate than TD children in recognizing both the emotional and neutral BM, either when presented as FLDs or PLDs. These results suggest that the difficulty in understanding the observed BM may rely on atypical processing of BM information rather than emotion. Moreover, we found that the accuracy improved with age and IQ only in children with ASD without ID, suggesting that high level of cognitive resources can mediate the acquisition of compensatory mechanisms which develop with age.

Face and body perception is mediated by configural mechanisms, which allow the perception of these stimuli as a whole, rather than the sum of individual parts. Indirect measures of configural processing in visual cognition are the face and body inversion effects (FIE and BIE), which refer to the drop in performance when these stimuli are perceived upside-down. Albeit FIE and BIE have been well characterized at the behavioral level, much still needs to be understood in terms of the neurophysiological correlates of these effects. Thus, in the current study, the brain's electrical activity has been recorded by a 128 channel electroencephalogram (EEG) in 24 healthy participants while perceiving (upright and inverted) faces, bodies and houses. EEG data were analyzed in both the time domain (i.e., event-related potentials-ERPs) and the frequency domain [i.e., induced theta (5-7 Hz) and gamma (28-45 Hz) oscillations]. ERPs amplitude results showed increased N170 amplitude for inverted faces and bodies (compared to the same stimuli presented in canonical position) but not for houses. ERPs latency results showed delayed N170 components for inverted (vs. upright) faces, houses, but not bodies. Spectral analysis of induced oscillations indicated physiological FIE and BIE; that is decreased gamma-band synchronization over right occipito-temporal electrodes for inverted (vs. upright) faces, and increased bilateral frontoparietal theta-band synchronization for inverted (vs. upright) faces. Furthermore, increased left occipito-temporal and right frontal theta-band synchronization for upright (vs. inverted) bodies was found. Our findings, thus, demonstrate clear differences in the neurophysiological correlates of face and body perception. The neurophysiological FIE suggests disruption of feature binding processes (decrease in occipital gamma oscillations for inverted faces), together with enhanced feature-based attention (increase in frontoparietal theta oscillations for inverted f