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Non-invasive brain stimulation (NIBS) techniques, such as transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES), are widely employed in cognitive neuroscience to identify causal links between specific brain structures supporting sensory, motor, cognitive and affective functions. During the last decade, NIBS techniques have been increasingly applied to the study of the neural basis of creative thinking and aesthetic perception and appreciation. The present chapter offers an overview of mechanisms of actions of TMS and different types of tES and considers recent studies applying these techniques to shed light on the neural underpinning mediating creativity and the emergence of aesthetic experience. Available findings suggest the existence of some areas of overlap between the neural correlates of creativity and aesthetic experience mainly within prefrontal and parietal cortices (core nodes of the executive control and default mode networks); however, sensorimotor regions and low-level visual areas seem to be selectively dedicated to aesthetic experience of visual stimuli. In the concluding part, we consider current limitations and challenges in using NIBS and suggest future avenues for scientific exploration within these fields to fully exploit the great potential of brain stimulation to the study of the neural bases of creativity and aesthetic experiences.

Humans are the only species capable of experiencing pleasure from esthetic stimuli, such as art and music. Neuroimaging evidence suggests that the left dorsolateral prefrontal cortex (DLPFC) plays a critical role in esthetic judgments, both in music and in visual art. In the last decade, non-invasive brain stimulation (NIBS) has been increasingly employed to shed light on the causal role of different brain regions contributing to esthetic appreciation. In Experiment #1, musician (N = 20) and non-musician (N = 20) participants were required to judge musical stimuli in terms of “liking” and “emotions”. No significant differences between groups were found, although musicians were slower than non-musicians in both tasks, likely indicating a more analytic judgment, due to musical expertise. Experiment #2 investigated the putative causal role of the left dorsolateral pre-frontal cortex (DLPFC) in the esthetic appreciation of music, by means of transcranial direct current stimulation (tDCS). Unlike previous findings in visual art, no significant effects of tDCS were found, suggesting that stimulating the left DLPFC is not enough to affect the esthetic appreciation of music, although this conclusion is based on negative evidence.

The lateral occipital cortex (LO) has been shown to code the presence of both vertical and horizontal visual symmetry in dot patterns. However, the specific time window at which LO is causally involved in symmetry encoding has not been investigated. This was assessed using a chronometric transcranial magnetic stimulation (TMS) approach. Participants were presented with a series of dot configurations and instructed to judge whether they were symmetric along the vertical axis or not while receiving a double pulse of TMS over either the right LO (rLO) or the vertex (baseline) at different time windows (ranging from 50 ms to 290 ms from stimulus onset). We found that TMS delivered over the rLO significantly decreased participants’ accuracy in discriminating symmetric from non-symmetric patterns when TMS was applied between 130 ms and 250 ms from stimulus onset, suggesting that LO is causally involved in symmetry perception within this time window. These findings confirm and extend prior neuroimaging and ERP evidence by demonstrating not only that LO is causally involved in symmetry encoding but also that its contribution occurs in a relatively large temporal window, at least in tasks requiring fast discrimination of mirror symmetry in briefly (75 ms) presented patterns as in our study.

Prolonged periods of restrictions on people's freedom of movement during the first massive wave of the COVID-19 pandemic meant that most people engaged in all their daily activities at home. This suggested the need for the spatial features of the home and its occupants' perception of them to be investigated in terms of people's wellbeing. The present study was conducted on a large sample (N = 1354) drawn from different Italian regions. It examined the relationship between the “objective” and “subjective” dimensions of the home, measured in terms of objective home crowding and satisfaction with the space at home, in relation to perceived stress and the perceived risk of COVID-19 infection during the lockdown. The results showed that perceived stress is influenced by objective home crowding through the mediation of satisfaction with the space at home. These associations were more pronounced in younger generations. The negative association between satisfaction with the space at home and perceived stress was higher, the lower the perceived COVID-19 risk.

Deaf individuals may report difficulties in social interactions. However, whether these difficulties depend on deafness affecting social brain circuits is controversial. Here, we report the first meta-analysis comparing brain activations of hearing and (prelingually) deaf individuals during social perception. Our findings showed that deafness does not impact on the functional mechanisms supporting social perception. Indeed, both deaf and hearing control participants recruited regions of the action observation network during performance of different social tasks employing visual stimuli, and including biological motion perception, face identification, action observation, viewing, identification and memory for signs and lip reading. Moreover, we found increased recruitment of the superior-middle temporal cortex in deaf individuals compared with hearing participants, suggesting a preserved and augmented function during social communication based on signs and lip movements. Overall, our meta-analysis suggests that social difficulties experienced by deaf individuals are unlikely to be associated with brain alterations but may rather depend on non-supportive environments.

Interpersonal space (IPS) is the area surrounding our own bodies in which we interact comfortably with other individuals. During the COVID-19 pandemic, keeping larger IPS than usual, along with wearing a face mask, is one of the most effective measures to slow down the COVID-19 outbreak. Here, we explore the contribution of actual and perceived risk of contagion and anxiety levels in regulating our preferred social distance from other people during the first wave of the COVID-19 pandemic in Italy. In this study, 1293 individuals from six Italian regions with different levels of actual risk of infection participated in an online survey assessing their perceived risk to be infected, level of anxiety and IPS. Two tasks were adopted as measures of interpersonal distance: the Interpersonal Visual Analogue Scale and a questionnaire evaluating interpersonal distance with and without face mask. The results showed that the IPS regulation was affected by how people subjectively perceived COVID-19 risk and the related level of anxiety, not by actual objective risk. This clarifies that the role of threat in prompting avoidant behaviors expressed in increased IPS does not merely reflect environmental events but rather how they are subjectively experienced and represented.

Social cognition skills are typically acquired on the basis of visual information (e.g., the observation of gaze, facial expressions, gestures). In light of this, a critical issue is whether and how the lack of visual experience affects neurocognitive mechanisms underlying social skills. This issue has been largely neglected in the literature on blindness, despite difficulties in social interactions may be particular salient in the life of blind individuals (especially children). Here we provide a meta-analysis of neuroimaging studies reporting brain activations associated to the representation of self and others' in early blind individuals and in sighted controls. Our results indicate that early blindness does not critically impact on the development of the “social brain,” with social tasks performed on the basis of auditory or tactile information driving consistent activations in nodes of the action observation network, typically active during actual observation of others in sighted individuals. Interestingly though, activations along this network appeared more left-lateralized in the blind than in sighted participants. These results may have important implications for the development of specific training programs to improve social skills in blind children and young adults.

Evidence suggests that the posterior cerebellum is involved in emotional processing. Specific mechanisms by which the cerebellum contributes to the perception of and reaction to the emotional state of others are not well-known. It is likely that perceived emotions trigger anticipatory/preparatory motor changes. However, the extent to which the cerebellum modulates the activity of the motor cortex to contribute to emotional processing has not been directly investigated. In this study, we assessed whether the activity of the posterior cerebellum influences the modulation of motor cortical excitability in response to emotional stimuli. To this end, we transiently disrupted the neural activity of the left posterior cerebellum using 1 Hz repetitive transcranial magnetic stimulation (rTMS) and examined its effect on motor cortical excitability witnessed during emotional face processing (in comparison to the effects of sham rTMS). Motor excitability was measured as TMS-based motor evoked potentials (MEPs) recorded from bilateral first dorsal interosseous (FDI) muscles during the viewing of negative emotional (i.e. fearful) and neutral facial expressions. In line with previous evidence, we found that MEP amplitude was increased during the viewing of fearful compared to neutral faces. Critically, when left posterior cerebellar activity was transiently inhibited with 1 Hz rTMS, we observed a reduction in amplitude of MEPs recorded from the contralateral (right) motor cortex during the viewing of emotional (but not neutral) faces. In turn, inhibition of the left posterior cerebellum did not affect the amplitude of MEPs recorded from the ipsilateral motor cortex. Our findings suggest that the posterolateral (left) cerebellum modulates motor cortical response to negative emotional stimuli and may serve as an interface between limbic, cognitive, and motor systems.

Neurologically intact individuals usually show a leftward bias in spatial attention, known as pseudoneglect, likely reflecting a right-hemisphere dominance in the control of spatial attention. A leftward bias also seems to manifest when individuals are asked to provide aesthetic judgments about visual stimuli, like artworks. However, whether artwork perception affects the allocation of spatial attention has never been directly investigated. Here, we assessed whether viewing figurative paintings affects hemispheric imbalance in the control of spatial attention by asking participants to bisect a series of lines presented on a grey background, on figurative paintings or on non-artistic photographs of real-world scenes, while either simply observing or explicitly evaluating each image. In line with previous evidence, participants showed a leftward bisection bias in the baseline condition, reflecting pseudoneglect. Critically, the presence of a painting in the background (irrespective of whether an aesthetic evaluation was required or not) significantly shifted the bias further to the left compared to when lines were bisected over a grey background (baseline) or a photographed scene. This finding suggests that perception of visual art may affect the control of spatial attention, possibly tapping on right-hemisphere resources related to visuospatial exploration, regardless of reward apprehension mechanisms (at least when images do not evoke strong emotional reactions leading to polarized like/dislike judgements).

The human cerebral cortex is asymmetrically organized with hemispheric lateralization pervading nearly all neural systems of the brain. Whether the lack of normal visual development affects hemispheric specialization subserving the deployment of visuospatial attention asymmetries is controversial. In principle, indeed, the lack of early visual experience may affect the lateralization of spatial functions, and the blind may rely on a different sensory input compared to the sighted. In this review article, we thus present a current state-of-the-art synthesis of empirical evidence concerning the effects of visual deprivation on the lateralization of various spatial processes (i.e., including line bisection, mirror symmetry, and localization tasks). Overall, the evidence reviewed indicates that spatial processes are supported by a right hemispheric network in the blind, hence, analogously to the sighted. Such a right-hemisphere dominance, however, seems more accentuated in the blind as compared to the sighted as indexed by the greater leftward bias shown in different spatial tasks. This is possibly the result of the more pronounced involvement of the right parietal cortex during spatial tasks in blind individuals compared to the sighted, as well as of the additional recruitment of the right occipital cortex, which would reflect the cross-modal plastic phenomena that largely characterize the blind brain.

It has been hypothesized that embodied mechanisms encompassing the simulation of actions, emotions and corporeal sensations contribute to aesthetic appreciation of art. In line with this, in this study we assessed whether there is a relationship between the extent to which an artwork triggers motor resonance mechanisms and liking for the artwork. To this aim, we measured motor evoked potentials (MEPs) induced by TMS over M1 whilst participants viewed a series of paintings depicting either humans in static postures or performing dynamic actions, and paintings depicting static or dynamic non-human scenes. Following recording of MEPs, participants indicated how much they liked each painting and found the painting to be dynamic. Viewing of paintings depicting dynamic human actions was associated with a significant increase in MEPs size compared to baseline and to viewing of the other paintings. The more the painting conveyed the impression of a dynamic human action, the higher the MEPs amplitude and the more the artwork was liked. However, liking per se was not related to MEPs size. In fact, the positive relationship between MEPs size and preference for paintings depicting humans was entirely mediated by the perceived dynamism of the portrayed actions, and no positive relationship was observed between subjective preference for paintings depicting landscapes/objects and MEPs size. Overall, our data contribute to shed light on the possible role of embodied resonance mechanisms in aesthetic appreciation of visual art, and show that characterization of motor cortical excitability may serve as a promising approach in neuroaesthetics.

Humans tend to prefer order to disorder. Orderly environments may provide individuals with comfort due to predictability, allowing a more efficient interaction with objects. Accordingly, a disorderly environment may elicit a tendency to restore order. This order restoration tendency may be observed physiologically as modulation within corticospinal excitability; the latter has been previously associated with motor preparation. To test these hypothesized physiological indices of order restoration, we measured possible changes in corticospinal excitability, as reflected by the amplitude of motor-evoked potentials (MEPs) elicited by single-pulse transcranial magnetic stimulation (TMS) over the primary motor cortex while participants viewed ordered and disordered rooms. We found that images depicting disorderly environments suppressed excitability within the corticospinal tract, in line with prior findings that motor preparation is typically associated with decreased corticospinal excitability. Interestingly, this pattern was particularly evident in individuals that displayed subclinical levels of obsessive-compulsive traits. Thus, a disorderly environment may move the motor system to restore a disorderly environment into a more orderly and predictable environment, and preparation for “order” may be observed on a sensorimotor basis.

The cerebellum is increasingly attracting scientists interested in basic and clinical research of neuromodulation. Here, we review available studies that used either transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) to examine the role of the posterior cerebellum in different aspects of social and affective cognition, from mood regulation to emotion discrimination, and from the ability to identify biological motion to higher-level social inferences (mentalizing). We discuss how at the functional level the role of the posterior cerebellum in these different processes may be explained by a generic prediction mechanism and how the posterior cerebellum may exert this function within different cortico-cerebellar and cerebellar limbic networks involved in social cognition. Furthermore, we suggest to deepen our understanding of the cerebro-cerebellar circuits involved in different aspects of social cognition by employing promising stimulation approaches that have so far been primarily used to study cortical functions and networks, such as paired-pulse TMS, frequency-tuned stimulation, state-dependent protocols, and chronometric TMS. The ability to modulate cerebro-cerebellar connectivity opens up possible clinical applications for improving impairments in social and affective skills associated with cerebellar abnormalities.

Visual processing of human movements is critical for adaptive social behavior. Cerebellar activations have been observed during biological motion discrimination in prior neuroimaging studies, and cerebellar lesions may be detrimental for this task. However, whether the cerebellum plays a causal role in biological motion discrimination has never been tested. Here, we addressed this issue in three different experiments by interfering with the posterior cerebellar lobe using transcranial magnetic stimulation (TMS) during a biological discrimination task. In Experiments 1 and 2, we found that TMS delivered at onset of the visual stimuli over the vermis (vermal lobule VI), but not over the left cerebellar hemisphere (left lobule VI/Crus I), interfered with participants' ability to distinguish biological from scrambled motion compared to stimulation of a control site (vertex). Interestingly, when stimulation was delivered at a later time point (300 ms after stimulus onset), participants performed worse when TMS was delivered over the left cerebellar hemisphere compared to the vermis and the vertex (Experiment 3). Our data show that the posterior cerebellum is causally involved in biological motion discrimination and suggest that different sectors of the posterior cerebellar lobe may contribute to the task at different time points.

Consistent evidence suggests that the cerebellum contributes to the processing of emotional facial expressions. However, it is not yet known whether the cerebellum is recruited when emotions are expressed by body postures or movements, or whether it is recruited differently for positive and negative emotions. In this study, we asked healthy participants to discriminate between body postures (with masked face) expressing emotions of opposite valence (happiness vs anger, Experiment 1), or of the same valence (negative: anger vs sadness; positive: happiness vs surprise, Experiment 2). While performing the task, participants received online transcranial magnetic stimulation (TMS) over a region of the posterior left cerebellum and over two control sites (early visual cortex and vertex). We found that TMS over the cerebellum affected participants' ability to discriminate emotional body postures, but only when one of the emotions was negatively valenced (i.e. anger). These findings suggest that the cerebellar region we stimulated is involved in processing the emotional content conveyed by body postures and gestures. Our findings complement prior evidence on the role of the cerebellum in emotional face processing and have important implications from a clinical perspective, where non-invasive cerebellar stimulation is a promising tool for the treatment of motor, cognitive and affective deficits.

Patients with Parkinson disease (PD) may show impairments in the social perception. Whether these deficits have been consistently reported, it remains to be clarified which brain alterations subtend them. To this aim, we conducted a neuroimaging meta-analysis to compare the brain activity during social perception in patients with PD versus healthy controls. Our results show that PD patients exhibit a significantly decreased response in the basal ganglia (putamen and pallidum) and a trend toward decreased activity in the mirror system, particularly in the left parietal cortex (inferior parietal lobule and intraparietal sulcus). This reduced activation may be tied to a disruption of cognitive resonance mechanisms and may thus constitute the basis of impaired others’ representations underlying action and emotion perception. We also found increased activation in the posterior cerebellum in PD, although only in a within-group analysis and not in comparison with healthy controls. This cerebellar activation may reflect compensatory mechanisms, an aspect that deserves further investigation. We discuss the clinical implications of our findings for the development of novel social skill training programs for PD patients.

While the discussion on the foundations of social understanding mainly revolves around the notions of empathy, affective mentalizing, and cognitive mentalizing, their degree of overlap versus specificity is still unclear. We took a meta-analytic approach to unveil the neural bases of cognitive mentalizing, affective mentalizing, and empathy, both in healthy individuals and pathological conditions characterized by social deficits such as schizophrenia and autism. We observed partially overlapping networks for cognitive and affective mentalizing in the medial prefrontal, posterior cingulate, and lateral temporal cortex, while empathy mainly engaged fronto-insular, somatosensory, and anterior cingulate cortex. Adjacent process-specific regions in the posterior lateral temporal, ventrolateral, and dorsomedial prefrontal cortex might underpin a transition from abstract representations of cognitive mental states detached from sensory facets to emotionally-charged representations of affective mental states. Altered mentalizing-related activity involved distinct sectors of the posterior lateral temporal cortex in schizophrenia and autism, while only the latter group displayed abnormal empathy related activity in the amygdala. These data might inform the design of rehabilitative treatments for social cognitive deficits.

Congenital or acquired cerebellum alterations are associated with a complex pattern of motor, cognitive and social disorders. These disturbances may reflect the involvement of the cerebellum in generating and updating the internal models that sub-serve-the prediction of sensory events. Here, we tested whether the cerebellar involvement in using contextual expectations to interpret ambiguous sensory sceneries is specific for social actions or also extends to physical events. We applied anodic, cathodic and sham cerebellar transcranial Direct Current Stimulation (ctDCS) to modulate the performance of an adult sample in two tasks requiring the prediction of social actions or moving shapes. For both tasks, in an earlier implicit-learning phase (familiarization), we manipulated the probability of co-occurrence between a particular action/shape and contextual elements, which could provide either strongly or moderately informative expectations. The use of these expectations was then tested when participants had to predict the unfolding of temporally occluded videos, in situations of perceptual uncertainty (testing). Results showed that in the testing, but not in the familiarization phase, cathodic as compared to anodic and sham ctDCS hindered participants’ sensitivity in predicting actions embedded in strongly, but not moderately, informative contexts. Conversely, anodic as compared to sham ctDCS boosted the prediction of actions embedded in moderately, but not strongly, informative contexts. We observed no ctDCS effects for the shape prediction task, thus pointing to a specific involvement of the cerebellum in forming expectations related to social events. Our results encourage the exploration of rehabilitative effects of ctDCS in patients with social perception deficits.

The effects of online Transcranial Magnetic Stimulation (TMS) can qualitatively vary as a function of brain state. For example, TMS intensities which normally impair performance can have a facilitatory effect if the targeted neuronal representations are in a suppressed state. These phenomena have been explained in terms of the existence of distinct facilitatory and suppressive ranges as a function of TMS intensity which are shifted by changes in neural excitability. We tested this model by applying TMS at a low (60% of phosphene threshold) or high (120% of phosphene threshold) intensity during a priming paradigm. Our results show that state-dependent TMS effects vary qualitatively as a function of TMS intensity. Whereas the application of TMS at 120% of participants' phosphene threshold impaired performance on fully congruent trials (in effect, reducing the benefit of priming), TMS applied at a lower intensity (60% of phosphene threshold), facilitated performance on congruent trials. These results demonstrate that behavioral effects of TMS reflect a nonlinear interaction between initial activation state and TMS intensity. They also provide support for the existence of facilitatory/suppressive ranges of TMS effects which shift when neural excitability changes.

Growing evidence suggests that the cerebellum is not only involved in motor functions, but it significantly contributes to sensory and cognitive processing as well. In particular, it has been hypothesized that the cerebellum identifies recurrent serial events and recognizes their violations. Here we used transcranial magnetic stimulation (TMS) to shed light on the role of the cerebellum in short-term memory of visual sequences. In two experiments, we found that TMS over the right cerebellar hemisphere impaired participants' ability to recognize the correct order of appearance of geometrical stimuli varying in shape and/or size. In turn, cerebellar TMS did not affect recognition of highly familiar short sequences of letters or numbers. Overall, our data suggest that the cerebellum is involved in memorizing the order in which (concatenated) stimuli appear, this process being important for sequence learning

Growing evidence suggests that the cerebellum plays a critical role in non-motor functions, contributing to cognitive and affective processing. In particular, the cerebellum might represent an important node of the “limbic” network, underlying not only emotion regulation but also emotion perception and recognition. Here, we used transcranial magnetic stimulation (TMS) to shed further light on the role of the cerebellum in emotional perception by specifically testing cerebellar contribution to explicit and incidental emotional processing. In particular, in three different experiments, we found that TMS over the (left) cerebellum impaired participants’ ability to categorize facial emotional expressions (explicit task) and to classify the gender of emotional faces (incidental emotional processing task), but not the gender of neutral faces. Overall, our results indicate that the cerebellum is involved in perceiving the emotional content of facial stimuli, even when this is task irrelevant

The occipital face area (OFA) has been shown to code the presence of symmetry in faces and in vertically symmetric dot patterns. However, it is not clear whether symmetry processing of face and non-face stimuli involve overlapping neural mechanisms in OFA. This was assessed using state-dependent TMS by employing a priming paradigm. Specifically, we examined whether prior presentation of low-level symmetry affects the impact of TMS on discrimination of symmetry in subsequently presented faces – indicating that the same neural mechanisms encode symmetry in both face and non-face stimuli. Participants performed a symmetry discrimination task on a series of faces, each of which was preceded by either a vertically symmetric, a horizontally symmetric or a non-symmetric dot configuration (prime) while receiving stimulation over either the right OFA, the right Lateral Occipital Cortex (rLO) or over a control site (Vertex). Vertically symmetric dot patterns primed symmetry discrimination in faces. The key finding was that the priming effect was not affected by TMS applied over OFA; stimulation of this site (but not of rLO) impaired the discrimination of facial symmetry regardless of prime type. Overall, these results suggest that distinct neural representations in OFA are involved in symmetry detection in face and non-face stimuli.

Noninvasive brain stimulation (NIBS) techniques, such as transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (tES), are largely employed in cognitive neuroscience to investigate the brain-behavior relationship. During the last decade, non-invasive brain stimulation techniques have been increasingly employed in the field of neuroaesthetics research to shed light on the possible causal role of different brain regions contributing to aesthetic appreciation. This chapter provides a synthetic description of mechanisms of actions of TMS and different types of tES, and reviews recent NIBS studies that have shed light on the neural underpinning of aesthetic evaluation of (visual) artworks. The chapter also considers methodological limitations of the reviewed studies and the future potential for non-invasive brain stimulation to significantly contribute to the understanding of the neural bases of visual aesthetic experiences. © Oxford University Press 2022. All rights reserved.

Visual attentive tracking requires a balance of excitation and inhibition across large-scale frontoparietal cortical networks. Using methods borrowed from network science, we characterize the induced changes in network dynamics following low frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) as an inhibitory noninvasive brain stimulation protocol delivered over the intraparietal sulcus. When participants engaged in visual tracking, we observed a highly stable network configuration of six distinct communities, each with characteristic properties in node dynamics. Stimulation to parietal cortex had no significant impact on the dynamics of the parietal community, which already exhibited increased flexibility and promiscuity relative to the other communities. The impact of rTMS, however, was apparent distal from the stimulation site in lateral prefrontal cortex. rTMS temporarily induced stronger allegiance within and between nodal motifs (increased recruitment and integration) in dorsolateral and ventrolateral prefrontal cortex, which returned to baseline levels within 15 min. These findings illustrate the distributed nature by which inhibitory rTMS perturbs network communities and is preliminary evidence for downstream cortical interactions when using noninvasive brain stimulation for behavioral augmentations.

Although converging evidence suggests that the posterior cerebellum is involved in visuospatial functions and in the orienting of attention, a clear topography of cerebellar regions causally involved in the control of spatial attention is still missing. In this study, we aimed to shed light on this issue by using online neuronavigated transcranial magnetic stimulation (TMS) to temporarily interfere with posterior medial (Vermis lobule VII) and left lateral (Crus I/II) cerebellar activity during a task measuring visuospatial (landmark task, Experiment 1 and 2) and representational (number bisection task, Experiment 2) asymmetries in the orienting of attention. At baseline, participants showed attentional biases consistent with the literature, that is a leftward and upward bias with horizontal and vertical lines, respectively, and a leftward bias in number bisection. Critically, TMS over the left cerebellar hemisphere significantly counteracted pseudoneglect in the number bisection task, whilst not affecting attentional biases in the landmark task. In turn, TMS over the posterior vermis did not affect performance in either task. Taken together, our findings suggest that the left posterior cerebellar hemisphere (but not the posterior vermis) is a critical node of an extended brain network subtending the control of spatial attention, at least when attention needs to be allocated to an internal representational space and a certain degree of mental manipulation is required (as in the number bisection task).

The traditional view on the cerebellum is that it controls motor behavior. Although recent work has revealed that the cerebellum supports also nonmotor functions such as cognition and affect, only during the last 5 years it has become evident that the cerebellum also plays an important social role. This role is evident in social cognition based on interpreting goal-directed actions through the movements of individuals (social “mirroring”) which is very close to its original role in motor learning, as well as in social understanding of other individuals’ mental state, such as their intentions, beliefs, past behaviors, future aspirations, and personality traits (social “mentalizing”). Most of this mentalizing role is supported by the posterior cerebellum (e.g., Crus I and II). The most dominant hypothesis is that the cerebellum assists in learning and understanding social action sequences, and so facilitates social cognition by supporting optimal predictions about imminent or future social interaction and cooperation. This consensus paper brings together experts from different fields to discuss recent efforts in understanding the role of the cerebellum in social cognition, and the understanding of social behaviors and mental states by others, its effect on clinical impairments such as cerebellar ataxia and autism spectrum disorder, and how the cerebellum can become a potential target for noninvasive brain stimulation as a therapeutic intervention. We report on the most recent empirical findings and techniques for understanding and manipulating cerebellar circuits in humans. Cerebellar circuitry appears now as a key structure to elucidate social interactions.

Humans show a tendency to represent pitch in a spatial format. A classical finding supporting this spatial representation is the Spatial–Musical Association of Response Codes (SMARC) effect, reflecting faster responses to low tones when pressing a left/bottom-side key and to high tones when pressing a right/top-side key. Despite available evidence suggesting that the horizontal and vertical SMARC effect may be differently modulated by instrumental expertise and musical timbre, no study has so far directly explored this hypothesis in a unified framework. Here, we investigated this possibility by comparing the performance of professional pianists, professional clarinettists and non-musicians in an implicit timbre judgement task, in both horizontal and vertical response settings. Results showed that instrumental expertise significantly modulates the SMARC effect: whereas in the vertical plane a comparable SMARC effect was observed in all groups, in the horizontal plane the SMARC effect was significantly modulated by the specific instrumental expertise, with pianists showing a stronger pitch–space association compared to clarinettists and non-musicians. Moreover, the influence of pitch along the horizontal dimension was stronger in those pianists who started the instrumental training at a younger age. Results also showed an influence of musical timbre in driving the horizontal, but not the vertical, SMARC effect, with only piano notes inducing a pitch–space association. Taken together, these findings suggest that sensorimotor experience due to instrumental training and musical timbre affect the mental representation of pitch on the horizontal space, whereas the one on the vertical space would be mainly independent from musical practice.

During the last decade, non-invasive brain stimulation techniques have been increasingly employed in the field of neuroaesthetics research to shed light on the possible causal role of different brain regions contributing to aesthetic appreciation. Here, I review studies that have employed transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) to investigate neurocognitive mechanisms mediating visual aesthetic appreciation for different stimuli categories (faces, bodies, paintings). The review first considers studies that have assessed the possible causal contribution of cortical regions in mediating aesthetic appreciation along the visual ventral and dorsal pathways (i.e., the extrastriate body area, the motion-sensitive region V5/MT+ , the lateral occipital complex and the posterior parietal cortex). It then considers TMS and tDCS studies that have targeted premotor and motor regions, as well as other areas involved in body and facial expression processing (such as the superior temporal sulcus and the somatosensory cortex) to assess their role in aesthetic evaluation. Finally, it discusses studies that have targeted medial and dorsolateral prefrontal regions leading to significant changes in aesthetic appreciation for both biological stimuli (faces and bodies) and artworks. Possible mechanisms mediating stimulation effects on aesthetic judgments are discussed. A final section considers both methodological limitations of the reviewed studies (including levels of statistical power and the need for further replication) and the future potential for non-invasive brain stimulation to significantly contribute to the understanding of the neural bases of visual aesthetic experiences.

Among the brain regions involved in the aesthetic evaluation of paintings, the prefrontal cortex seems to play a pivotal role. In particular, consistent neuroimaging evidence indicates that activity in the dorsolateral prefrontal cortex (mainly in the left hemisphere) and in medial and orbital sectors of the prefrontal cortex is linked to viewing aesthetically pleasing images. In this study, we focused on the contribution of the medial prefrontal cortex (mPFC) in mediating aesthetic decisions about paintings. We found that enhancing excitability in this region via anodal tDCS led participants to judge paintings as more beautiful. Although significant, the effects were moderate, possibly due to the neutral affective value of the artworks we used, suggesting that activity in mPFC may be critically dependent on the affective impact of the paintings.

Prior studies have shown that strabismic amblyopes do not exhibit pseudoneglect in visual line bisection, suggesting that the right-hemisphere dominance in the control of spatial attention may depend on a normally developing binocular vision. In this study, we aimed to investigate whether an abnormal binocular childhood experience also affects spatial attention in the haptic modality, thus reflecting a supramodal effect. To this aim, we compared the performance of normally sighted, strabismic and early monocular blind participants in a visual and a haptic line bisection task. In visual line bisection, strabismic individuals tended to err to the right of the veridical midpoint, in contrast with normally sighted participants who showed pseudoneglect. Monocular blind participants exhibited high variability in their visual performance, with a tendency to bisect toward the direction of the functioning eye. In turn, in haptic bisection, all participants consistently erred towards the left of the veridical midpoint. Taken together, our findings support the view that pseudoneglect in the visual and haptic modality relies on different functional and neural mechanisms

Item does not contain fulltext, Infant signals, including infant sounds and facial expressions, play a critical role in eliciting parental proximity and care. Processing of infant signals in the adulthood brain is likely to recruit emotional empathy neural circuits, including the inferior frontal gyrus (IFG). Here, we used transcranial magnetic stimulation (TMS) to test the role of right IFG (rIFG) in behavioral responses to infant signals. Specifically, a group of nulliparous women were asked to perform a handgrip dynamometer task and an Approach-Avoidance Task (AAT) after receiving TMS over the right IFG or over a control site (vertex). Suppressing activity in the rIFG affected the modulation of handgrip force in response to infant crying. Moreover, the AAT showed that participants tend to avoid the sad infant face after Vertex stimulation, and this bias was counteracted by rIFG stimulation. Our results suggest a causal role of rIFG in sensitive responding towards sad infants and point to the rIFG as a critical node in the neural network underlying the innate releasing mechanism for feelings of love, affection and caring of sad infants.

Deaf individuals may compensate for the lack of the auditory input by showing enhanced capacities in certain visual tasks. Here we assessed whether this also applies to recognition of emotions expressed by bodily and facial cues. In Experiment 1, we compared deaf participants and hearing controls in a task measuring recognition of the six basic emotions expressed by actors in a series of video-clips in which either the face, the body, or both the face and body were visible. In Experiment 2, we measured the weight of body and face cues in conveying emotional information when intense genuine emotions are expressed, a situation in which face expressions alone may have ambiguous valence. We found that deaf individuals were better at identifying disgust and fear from body cues (Experiment 1) and in integrating face and body cues in case of intense negative genuine emotions (Experiment 2). Our findings support the capacity of deaf individuals to compensate for the lack of the auditory input enhancing perceptual and attentional capacities in the spared modalities, showing that this capacity extends to the affective domain.

Noninvasive brain stimulation methods, like transcranial magnetic stimulation and transcranial electrical stimulation, are largely employed in cognitive neuroscience to investigate brain–behavior relationships. This review offers an overview of mechanisms of actions of transcranial magnetic stimulation and different types of transcranial electrical stimulation and considers recent studies that have shed light on the neural underpinning of aesthetic evaluation of (visual) artworks by means of noninvasive brain stimulation. Possible future applications of noninvasive brain stimulation for research in neuroaesthetics are also discussed

Infant signals, including infant sounds and facial expressions, play a critical role in eliciting parental proximity and care. Processing of infant signals in the adulthood brain is likely to recruit emotional empathy neural circuits, including the inferior frontal gyrus (IFG). Here, we used transcranial magnetic stimulation (TMS) to test the role of right IFG (rIFG) in behavioral responses to infant signals. Specifically, a group of nulliparous women were asked to perform a handgrip dynamometer task and an Approach-Avoidance Task (AAT) after receiving TMS over the right IFG or over a control site (vertex). Suppressing activity in the rIFG affected the modulation of handgrip force in response to infant crying. Moreover, the AAT showed that participants tend to avoid the sad infant face after Vertex stimulation, and this bias was counteracted by rIFG stimulation. Our results suggest a causal role of rIFG in sensitive responding towards sad infants and point to the rIFG as a critical node in the neural network underlying the innate releasing mechanism for feelings of love, affection and caring of sad infants.

When viewing a portrait, we are often captured by its expressivity, even if the emotion depicted is not immediately identifiable. If the neural mechanisms underlying emotion processing of real faces have been largely clarified, we still know little about the neural basis of evaluation of (emotional) expressivity in portraits. In this study, we aimed at assessing—by means of transcranial magnetic stimulation (TMS)—whether the right superior temporal sulcus (STS) and the right somatosensory cortex (SC), that are important in discriminating facial emotion expressions, are also causally involved in the evaluation of expressivity of portraits. We found that interfering via TMS with activity in (the face region of) right STS significantly reduced the extent to which portraits (but not other paintings depicting human figures with faces only in the background) were perceived as expressive, without, though, affecting their liking. In turn, interfering with activity of the right SC had no impact on evaluating either expressivity or liking of either paintings’ category. Our findings suggest that evaluation of emotional cues in artworks recruit (at least partially) the same neural mechanisms involved in processing genuine biological others. Moreover, they shed light on the neural basis of liking decisions in art by art-naïve people, supporting the view that aesthetic appreciation relies on a multitude of factors beyond emotional evaluation

Converging evidence suggests that the perception of auditory pitch exhibits a characteristic spatial organization. This pitch–space association can be demonstrated experimentally by the Spatial Musical Association of Response Codes (SMARC) effect. This is characterized by faster response times when a low-positioned key is pressed in response to a low-pitched tone, and a high-positioned key is pressed in response to a high-pitched tone. To investigate whether the development of this pitch–space association is mediated by normal visual experience, we tested a group of early blind individuals on a task that required them to discriminate the timbre of different instrument sounds with varying pitch. Results revealed a comparable pattern in the SMARC effect in both blind participants and sighted controls, suggesting that the lack of prior visual experience does not prevent the development of an association between pitch height and vertical space