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Goal contagion, the tendency to adopt others' goals, significantly impacts cognitive processes, which gains particular importance in the emerging field of human-robot interactions. The present study explored how observing human versus robotic actions affects preference and memory. Series of objects undergoing either human or robotic grasping actions together with static (no action) objects were presented, while participants indicated their preference for each object. After a short delay, their memory for grasped, static and new (unstudied) stimuli was tested. Human actions enhanced preference and subsequent recollection of objects, more than robotic actions. In the context of human action, static objects were also perceived as more familiar at recognition. The goal contagion's influence on memory was found to be independent from its impact on preference. These findings highlight the critical role of human interaction in eliciting the impact of goal contagion on cognitive evaluations, memory engagement and the creation of detailed associative memories., (© 2024. The Author(s).)

The aesthetic values that individuals place on visual images are formed and shaped over a lifetime. However, whether the formation of visual aesthetic value is solely influenced by environmental exposure is still a matter of debate. Here, we considered differences in aesthetic value emerging across three visual domains: abstract images, scenes, and faces. We examined variability in two major dimensions of ordinary aesthetic experiences: taste-typicality and evaluation-bias. We build on two samples from the Australian Twin Registry where 1547 and 1231 monozygotic and dizygotic twins originally rated visual images belonging to the three domains. Genetic influences explained 26% to 41% of the variance in taste-typicality and evaluation-bias. Multivariate analyses showed that genetic effects were partially shared across visual domains. Results indicate that the heritability of major dimensions of aesthetic evaluations is comparable to that of other complex social traits, albeit lower than for other complex cognitive traits. The exception was taste-typicality for abstract images, for which we found only shared and unique environmental influences. Our study reveals that diverse sources of genetic and environmental variation influence the formation of aesthetic value across distinct visual domains and provides improved metrics to assess inter-individual differences in aesthetic value., (© 2024. The Author(s).)

Perceiving art is known to elicit motor cortex activation in an observer's brain. This motor activation has often been attributed to a covert approach response associated with the emotional valence of an art piece (emotional reaction hypothesis). However, recent accounts have proposed that aesthetic experiences could be grounded in the motor simulation of actions required to produce an art piece and of the sensorimotor states embedded in its subject (embodied aesthetic hypothesis). Here, we aimed to test these two hypotheses by assessing whether motor facilitation during artwork perception mirrors emotional or motor simulation processes. To this aim, we capitalized on single pulse transcranial magnetic stimulation revealing a two-stage motor coding of emotional body postures: an early, non-specific activation related to emotion processing and a later action-specific activation reflecting motor simulation. We asked art-naïve individuals to rate how much they liked a series of pointillist and brushstroke canvases; photographs of artistic gardens served as control natural stimuli. After an early (150 ms) or a later (300 ms) post-stimulus delay, motor evoked potentials were recorded from wrist-extensor and finger muscles that were more involved in brushstroke- and pointillist-like painting, respectively. Results showed that observing the two canvas styles did not elicit differential motor activation in the early time window for either muscle, not supporting the emotional reaction hypothesis. However, in support of the embodied aesthetic hypothesis, we found in the later time window greater motor activation responses to brushstroke than pointillist canvases for the wrist-extensor, but not for the finger muscle. Furthermore, this muscle-selective facilitation was associated with lower liking ratings of brushstroke canvases and with greater empathy dispositions. These findings support the claim that simulation of the painter's movements is crucial for aesthetic experience, by documenting a link between motor simulation, dispositional empathy, and subjective appreciation in artwork perception., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Numerous studies corroborated the idea that the sound of familiar motor acts triggers a muscle-specific replica of the perceived actions in the listener's brain. We recently contradicted this conclusion by demonstrating that the representation of newly-learned action-related sounds is not somatotopically organised but rather it corresponds to the goal a particular action aims to achieve. In the present study, we aimed at reconciling these results. We measured MEPs to TMS as an index of the functional correspondence between the sensory stimulation and the activity in the listener's motor cortex. Participants heard two tones of different pitch, void of previous motor meaning, before and after an acquisition phase in which they generated them by performing 400 free-choice button presses. We then disentangled the representation of the action goal (button-tone association) from the somatotopic (muscle-tone) association by reversing the muscle-button contingencies. Our result supports the hypothesis that the neuronal representations of action-related sounds depends on motor familiarity: perceptuomotor representations of newly-learned actions are muscle-independent and correspond to the button-tone contingencies, whilst longer-term practice results in representations that rely on lower-level intrinsic parameters associated with the kinematics of specific movements.

The conscious experience of being the author of our own actions is thought to be grounded in pre-reflective and low-level sensorimotor representations of the self as different from the other. It has been suggested that the inferior parietal lobe (IPL) is generally involved in self-other differentiation processes and in providing an explicit sense of action authorship. However, direct evidence for its causal and functional role in distinguishing self-related and other-related sensorimotor representations is lacking. The current study employed theta-burst stimulation (TBS) to condition left IPL's activity before a social version of the rubber hand illusion led participants to illusorily attribute observed finger movements to their own body. We recorded motor evoked potentials to single-pulse transcranial magnetic stimulation over the primary motor cortex (M1) as proxies of action authorship during action observation. The results showed that in a control condition (intermediate TBS over the left IPL) others' actions facilitated whereas self-attributed movements inhibited the motor system. Critically, continuous TBS disrupted this mismatch between self and other representations. This outcome provides direct evidence for the IPL's role in providing fundamental authorship signals for social differentiation in the human action system.

We like an object more when we see someone else reaching for it. To what extent is action observation causally linked to object valuation? In this study, we set out to answer to this question by applying continuous theta burst stimulation (cTBS) over the left inferior parietal lobule (IPL). Previous studies pointed to this region as critical in the representation of others' actions and in tool manipulation. However, it is unclear to what extent IPL's involvement simply reflects action observation, rather than a casual role in objects' valuation. To clarify this issue, we measured cTBS-dependent modulations of participants' "mimetic preference ratings", i.e., the difference between the ratings of pairs of familiar objects that were (vs. were not) reached out for by other individuals. Our result shows that cTBS increased mimetic preference ratings for tools, when compared to a control condition without stimulation. This effect was selective for items that were reached for or manipulated by another individual, whilst it was not detected in non-tool objects. Although preliminary, this finding suggests that the automatic and covert simulation of an observed action, even when there is no intention to act on an object, influences explicit affective judgments for objects. This work supports embodied cognition theories by substantiating that our subjective preference is grounded in action.

To what extent is the mirror neuron mechanism malleable to experience? The answer to this question can help characterising its ontogeny and its role in social cognition. Some suggest that it develops through sensorimotor associations congruent with our own actions. Others argue for its extreme volatility that will encode any sensorimotor association in the environment. Here, we added to this debate by exploring the effects of short goal-directed 'mirror' and 'counter-mirror' trainings (a 'mirror' training is defined as the first type of training encountered by the participants) on human auditory mirror motor-evoked potentials (MEPs). We recorded MEPs in response to two tones void of previous motor meaning, before and after mirror and counter-mirror trainings in which participants generated two tones of different pitch by performing free-choice button presses. The results showed that mirror MEPs, once established, were protected against an equivalent counter-mirror experience: they became manifest very rapidly and the same number of training trials that lead to the initial association did not suffice to reverse the MEP pattern. This steadiness of the association argues that, by serving direct-matching purposes, the mirror mechanism is a good solution for social cognition., (© The Author (2017). Published by Oxford University Press.)

The search for the underlying neural activation that occurs during subjective aesthetic experiences of artwork has been enhanced through neuroimaging techniques. Recently, the dorsolateral prefrontal cortex, alongside the orbitofrontal cortex, have been implicated in aesthetic appreciation, and this is the focus of the present paper. Here, the validity of this conclusion is examined through the discussion of its neuroanatomical connections and functional properties. It is proposed that the experimental evidence challenges the view that this area could hold a privileged position in a brain network involved in aesthetic preference.

Action observation activates the observer's motor system. These motor resonance responses are automatic and triggered even when the action is only implied in static snapshots. However, it is largely unknown whether an action needs to be consciously perceived to trigger motor resonance. In this study, we used single-pulse TMS to study the facilitation of corticospinal excitability (a measure of motor resonance) during supraliminal and subliminal presentations of implied action images. We used a forward and backward dynamic masking procedure that successfully prevented the conscious perception of prime stimuli depicting a still hand or an implied abduction movement of the index or little finger. The prime was followed by the supraliminal presentation of a still or implied action probe hand. Our results revealed a muscle-specific increase of motor facilitation following observation of the probe hand actions that were consciously perceived as compared with observation of a still hand. Crucially, unconscious perception of prime hand actions presented before probe still hands did not increase motor facilitation as compared with observation of a still hand, suggesting that motor resonance requires perceptual awareness. However, the presentation of a masked prime depicting an action that was incongruent with the probe hand action suppressed motor resonance to the probe action such that comparable motor facilitation was recorded during observation of implied action and still hand probes. This suppression of motor resonance may reflect the processing of action conflicts in areas upstream of the motor cortex and may subserve a basic mechanism for dealing with the multiple and possibly incongruent actions of other individuals.

Joint actions require the integration of simultaneous self- and other-related behaviour. Here, we investigated whether this function is underpinned by motor simulation, that is the capacity to represent a perceived action in terms of the neural resources required to execute it. This was tested in a music performance experiment wherein on-line brain stimulation (double-pulse transcranial magnetic stimulation, dTMS) was employed to interfere with motor simulation. Pianists played the right-hand part of piano pieces in synchrony with a recording of the left-hand part, which had (Trained) or had not (Untrained) been practiced beforehand. Training was assumed to enhance motor simulation. The task required adaptation to tempo changes in the left-hand part that, in critical conditions, were preceded by dTMS delivered over the right primary motor cortex. Accuracy of tempo adaptation following dTMS or sham stimulations was compared across Trained and Untrained conditions. Results indicate that dTMS impaired tempo adaptation accuracy only during the perception of trained actions. The magnitude of this interference was greater in empathic individuals possessing a strong tendency to adopt others' perspectives. These findings suggest that motor simulation provides a functional resource for the temporal coordination of one's own behaviour with others in dynamic social contexts., (© The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.)

The creation of an artwork requires motor activity. To what extent is art appreciation divorced from that activity and to what extent is it linked to it? That is the question which we set out to answer. We presented participants with pointillist-style paintings featuring discernible brushstrokes and asked them to rate their liking of each canvas when it was preceded by images priming a motor act either compatible or incompatible with the simulation of the artist's movements. We show that action priming, when congruent with the artist's painting style, enhanced aesthetic preference. These results support the hypothesis that involuntary covert painting simulation contributes to aesthetic appreciation during passive observation of artwork.

Much research has been carried out to understand how human brains make sense of another agent in motion. Current views based on human adult and monkey studies assume a matching process in the motor system biased toward actions performed by conspecifics and present in the observer's motor repertoire. However, little is known about the neural correlates of action cognition in early ontogeny. In this study, we examined the processes involved in the observation of full body movements in 4-month-old infants using functional near-infrared spectroscopy to measure localized brain activation. In a 2 × 2 design, infants watched human or robotic figures moving in a smooth, familiar human-like manner, or in a rigid, unfamiliar robot-like manner. We found that infant premotor cortex responded more strongly to observe robot-like motion compared with human-like motion. Contrary to current views, this suggests that the infant motor system is flexibly engaged by novel movement patterns. Moreover, temporal cortex responses indicate that infants integrate information about form and motion during action observation. The response patterns obtained in premotor and temporal cortices during action observation in these young infants are very similar to those reported for adults. These findings thus suggest that the brain processes involved in the analysis of an agent in motion in adults become functionally specialized very early in human development.

The human tendency to imitate gestures performed by conspecifics is automatic in nature. However, whether this automatic imitation can be considered as a true imitative phenomenon or only as a special instance of spatial compatibility is still being debated. New evidence suggests that automatic imitation, otherwise known as 'imitative compatibility', shall be considered as a phenomenon that operates independently from spatial compatibility. So far there are only a few investigations directly aimed at identifying the neural structures dedicated to this process. In the present study, we applied double-pulse transcranial magnetic stimulation (TMS) over the parietal opercula to further investigate the role of these regions in coding imitative compatibility. We found that a temporary disruption of parietal opercula caused the reduction of the imitative compatibility relative to the sham condition. In particular, the TMS interference with the parietal opercula's activity modulated the imitative compatibility but not the spatial compatibility, suggesting that these two processes are likely to be independent., (© 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.)

The capacity to distinguish between one's own and others' behavior is a cognitive prerequisite for successful joint action. We employed a musical joint action task to investigate how the brain achieves this distinction. Pianists performed the right-hand part of piano pieces, previously learned bimanually, while the complementary left-hand part either was not executed or was (believed to be) played by a co-performer. This experimental setting served to induce a co-representation of the left-hand part reflecting either the self or the co-performer. Single-pulse transcranial magnetic stimulation was applied to the right primary motor cortex and motor-evoked potentials (MEPs) were recorded from the resting left forearm. Results show that corticospinal excitability was modulated by whether the representation of the left hand was associated with the self or the other, with the MEP amplitude being low and high, respectively. This result remained unchanged in a separate session where participants could neither see nor hear the other but still infer his presence by means of contextual information. Furthermore, the amplitude of MEPs associated with co-performer presence increased with pianists' self-reported empathy. Thus, the sociality of the context modulates action attribution at the level of the motor control system.

Background: Peripheral homonymous scotomas beyond 30° from fixation are rare. The paucity of publications describing such visual field defects might be attributed to various factors, including the absence of severe symptoms, routine visual field assessment restricted to the central 30° with automated perimetry, and the collateral circulation to the occipital cortex. The aim of this study was to correlate the brain lesions and perimetric findings in 2 unusual cases of peripheral homonymous scotomas, with the anatomic location of the optic radiation and primary visual cortex., Methods: Two patients with circumscribed homonymous scotomas beyond 30° related to infarcts in the intermediate area of the visual cortex are reported. We describe a new strategy, which relies on modern lesion analysis and stereotaxic probabilistic cytoarchitectonic maps, to accurately correlate the brain lesion site with the location of the peripheral homonymous visual field defects., Results: In Case 1, the posterior optic radiation was affected in its termination in the upper intermediate visual cortex. In Case 2, the lesion was located in the upper rostral portion of the primary visual cortex. In both, the most anterior part of the visual cortex and the occipital pole were intact, accounting for preservation of the central and most peripheral visual field. Additionally, correlation of the neuroimaging findings with commonly used maps of the representation of the visual field on the striate cortex suggested that our data were most consistent with the Holmes map., Conclusions: Modern lesion analysis and cytoarchitectonic maps, in combination with the existing retinotopic maps, may provide reliable clues for the localization of cerebral infarction and prognosis of homonymous visual field defects and may lead to a better understanding of the link between neuroanatomical landmarks and functional outcomes.

In the absence of visual information, our brain is able to recognize the actions of others by representing their sounds as a motor event. Previous studies have provided evidence for a somatotopic activation of the listener's motor cortex during perception of the sound of highly familiar motor acts. The present experiments studied (a) how the motor system is activated by action-related sounds that are newly acquired and (b) whether these sounds are represented with reference to extrinsic features related to action goals rather than with respect to lower-level intrinsic parameters related to the specific movements. TMS was used to measure the correspondence between auditory and motor codes in the listener's motor system. We compared the corticomotor excitability in response to the presentation of auditory stimuli void of previous motor meaning before and after a short training period in which these stimuli were associated with voluntary actions. Novel cross-modal representations became manifest very rapidly. By disentangling the representation of the muscle from that of the action's goal, we further showed that passive listening to newly learnt action-related sounds activated a precise motor representation that depended on the variable contexts to which the individual was exposed during testing. Our results suggest that the human brain embodies a higher-order audio-visuo-motor representation of perceived actions, which is muscle-independent and corresponds to the goals of the action.

The field of neuroaesthetics attracts attention from neuroscientists and artists interested in the neural underpinnings of esthetic experience. Though less studied than the neuroaesthetics of visual art, dance neuroaesthetics is a particularly rich subfield to explore, as it is informed not only by research on the neurobiology of aesthetics, but also by an extensive literature on how action experience shapes perception. Moreover, it is ideally suited to explore the embodied simulation account of esthetic experience, which posits that activation within sensorimotor areas of the brain, known as the action observation network (AON), is a critical element of the esthetic response. In the present study, we address how observers' esthetic evaluation of dance is related to their perceived physical ability to reproduce the movements they watch. Participants underwent functional magnetic resonance imaging while evaluating how much they liked and how well they thought they could physically replicate a range of dance movements performed by professional ballet dancers. We used parametric analyses to evaluate brain regions that tracked with degree of liking and perceived physical ability. The findings reveal strongest activation of occipitotemporal and parietal portions of the AON when participants view movements they rate as both esthetically pleasing and difficult to reproduce. As such, these findings begin to illuminate how the embodied simulation account of esthetic experience might apply to watching dance, and provide preliminary evidence as to why some people find enjoyment in an evening at the ballet.

A case of partial recovery after stroke and its associated brain reorganization in a chronic patient after combined brain computer interface (BCI) training and physiotherapy is presented. A multimodal neuroimaging approach based on fMRI and diffusion tensor imaging was used to investigate plasticity of the brain motor system in parallel with longitudinal clinical assessments. A convergent association between functional and structural data in the ipsilesional premotor areas was observed. As a proof of concept investigation, these results encourage further research on a specific role of BCI on brain plasticity and recovery after stroke., (Copyright © 2010 Society for Psychophysiological Research.)

Visual extinction is an intriguing defect of awareness in stroke patients, referring to the unsuccessful perception of contralesional events under conditions of competition. Previous studies have investigated the cortical and subcortical brain structures that, when damaged or inactivated, provoke visual extinction. The present experiment asked how lesions of subcortical structures may contribute to the appearance of visual extinction. We investigated whether lesions centering on right basal ganglia may induce dysfunction in distant, structurally intact cortical structures. Normalized perfusion-weighted MRI was used to identify structurally intact but abnormally perfused brain tissue, that is, zones that are receiving enough blood supply to remain structurally intact but not enough to function normally. We compared patients with right basal ganglia lesions showing versus not showing visual extinction. In the extinction patients, the contrast revealed cortical malperfusion that clustered around the right TPJ. It seems as if malfunction of this area is a critical aspect in visual extinction not only after cortical lesion but also in the case of subcortical basal ganglia damage. Our results support the idea that a normally functioning TPJ area plays a decisive role for the attentional network involved in detecting of visual stimuli under conditions of competition.

Previous statistical voxelwise lesion-behavior mapping (VLBM) studies have demonstrated that spatial neglect is associated with cortical and subcortical gray matter damage. However, it has also been suggested that the disorder may result from white matter injury. Our aim was to investigate the white matter connectivity in a large sample of 140 stroke patients. We combined a VLBM approach with the histological maps of the human white matter fiber tracts provided by the Jülich probabilistic cytoarchitectonic atlas. We found that damage of right perisylvian white matter connections-the superior longitudinal fasciculus, the inferior occipitofrontal fasciculus, and the superior occipitofrontal fasciculus-is a typical finding in patients with spatial neglect. However, the analysis also revealed that the largest portion of the lesion area, namely between 89.1% and 96.6%, affected brain structures other than the perisylvian white matter fiber tracts. Predominantly, these included gray matter structures such as the superior temporal, inferior parietal, inferior frontal, and insular cortices, as well as subcortically the putamen and the caudate nucleus. Damage of gray matter structures thus appears to be a strong predictor of spatial neglect.

Brain damage may induce a dysfunction of upright body position termed "pusher syndrome". Patients with such disorder suffer from an alteration of their sense of body verticality. They experience their body as oriented upright when actually tilted nearly 20 degrees to the ipsilesional side. Pusher syndrome typically is associated with posterior thalamic stroke; less frequently with extra-thalamic lesions. This argued for a fundamental role of these structures in our control of upright body posture. Here we investigated whether such patients may show additional functional or metabolic abnormalities outside the areas of brain lesion. We investigated 19 stroke patients with thalamic or with extra-thalamic lesions showing versus not showing misperception of body orientation. We measured fluid-attenuated inversion-recovery (FLAIR) imaging, diffusion-weighted imaging (DWI), and perfusion-weighted imaging (PWI). This allowed us to determine the structural damage as well as to identify the malperfused but structural intact tissue. Pusher patients with thalamic lesions did not show dysfunctional brain areas in addition to the ones found to be structurally damaged. In the pusher patients with extra-thalamic lesions, the thalamus was neither structurally damaged nor malperfused. Rather, these patients showed small regions of abnormal perfusion in the structurally intact inferior frontal gyrus, middle temporal gyrus, inferior parietal lobule, and parietal white matter. The results indicate that these extra-thalamic brain areas contribute to the network controlling upright body posture. The data also suggest that damage of the neural tissue in the posterior thalamus itself rather than additional malperfusion in distant cortical areas is associated with pusher syndrome. Hence, it seems as if the normal functioning of both extra-thalamic as well as posterior thalamic structures is integral to perceiving gravity and controlling upright body orientation in humans.

Early periventricular brain lesions can not only cause cerebral palsy, but can also induce a reorganization of language. Here, we asked whether these different functional consequences can be attributed to topographically distinct portions of the periventricular white matter damage. Eight patients with pre- and perinatally acquired left-sided periventricular brain lesions underwent focal transcranial magnetic stimulation to assess the integrity of cortico-spinal hand motor projections, and functional MRI to determine the hemispheric organization of language production. MRI lesion-symptom mapping revealed that two distinct portions of the periventricular lesions were critically involved in the disruption of cortico-spinal hand motor projections on the one hand and in the induction of language reorganization into the contra-lesional right hemisphere on the other hand. Both regions are located in a position compatible with the course of cortico-spinal/cortico-nuclear projections of the primary motor cortex in the periventricular white matter, as determined by the stereotaxic probabilistic cytoarchitectonic atlas developed by the Jülich group.

Objective: The anatomy of the human pupillary light reflex (PLR) pathway is a matter of debate. The aim of this study was twofold: namely, to investigate the association of a relative afferent pupillary defect (RAPD) in acquired suprageniculate lesions with the location and extent of the cerebral lesions. Further, we suggest a new strategy of lesion analysis by combining established techniques with the stereotaxic probabilistic cytoarchitectonic atlas developed by the Jülich group., Methods: Twenty-three patients with homonymous visual field defects participated in this study. The RAPD was quantified clinically by two independent examiners with graded neutral density filters (swinging flashlight test). Using MRI in each individual, cerebral regions commonly affected in patients with a RAPD but spared in patients without a RAPD were determined and subsequently assessed by using cytoarchitectonic probabilistic maps., Results: A RAPD was present in 10/23 patients. Comparison of patients showing a RAPD vs those not showing a RAPD revealed that a region including the course of the optic radiation at its early beginning in the temporal white matter is commonly associated with a RAPD., Conclusions: It was demonstrated that the pupillary light reflex (PLR) depends on the input of suprageniculate neurons, thus supporting the involvement of a cortical pathway also. The site of integration of cortical signals in relation to the PLR into the pupillomotor pathway may be located suprageniculately in the vicinity of the lateral geniculate nucleus. Moreover, the suggested combination of established lesion analysis techniques with the probabilistic cytoarchitectonic atlas turned out to be a very helpful amelioration of stroke data analyses.