Neural Circuits Involved in the Recognition of Actions Performed by Nonconspecifics: An fMRI Study

Action expectancy modulates activity in the mirror neuron system and mentalizing system

Action understanding involves two distinct processing levels that engage separate neural mechanisms: perception of concrete kinematic information and recognition of abstract action intentions. The mirror neuron system and the mentalizing system have both been linked to concrete action and abstract information processing, but their specific roles remain debatable. Here, we conducted a functional magnetic resonance imaging study with 26 participants who passively observed expected and unexpected actions. We performed whole-brain activation, region of interest, and effective connectivity analyses to investigate the neural correlates of these actions. Whole-brain activation analyses revealed that expected actions were associated with increased activation in the left medial superior frontal gyrus, while unexpected actions were linked to heightened activity in the left supramarginal gyrus, left superior parietal lobule, right inferior temporal gyrus, and left middle frontal gyrus. Region of interest analyses demonstrated that the left ventral premotor cortex exhibited greater activation during the observation of expected actions compared to unexpected actions, while the left inferior frontal gyrus, left superior parietal lobule, and left precuneus showed stronger activation during the observation of unexpected actions. Effective connectivity was observed between the left ventral premotor cortex and the left angular gyrus, left intraparietal sulcus, left dorsal premotor cortex, and left ventromedial prefrontal cortex with the middle frontal gyrus when observing unexpected, but not expected, actions. These findings suggest that expected actions are primarily processed by the mirror neuron system, whereas unexpected actions engage both the mirror neuron system and the mentalizing system, with these systems playing complementary roles in the understanding of unexpected actions.

Emotional facial expression and perioral motor functions of the human auditory cortex

OBJECTIVE

We investigated the role of transverse temporal gyrus and adjacent cortex (TTG+) in facial expressions and perioral movements.

METHODS

In 31 patients undergoing stereo-electroencephalography monitoring, we describe behavioral responses elicited by electrical stimulation within the TTG+. Task-induced high-gamma modulation (HGM), auditory evoked responses, and resting-state connectivity were used to investigate the cortical sites having different types of responses on electrical stimulation.

RESULTS

Changes in facial expressions and perioral movements were elicited on electrical stimulation within TTG+ in 9 (29%) and 10 (32%) patients, respectively, in addition to the more common language responses (naming interruptions, auditory hallucinations, paraphasic errors). All functional sites showed auditory task induced HGM and evoked responses validating their location within the auditory cortex, however, motor sites showed lower peak amplitudes and longer peak latencies compared to language sites. Significant first-degree connections for motor sites included precentral, anterior cingulate, parahippocampal, and anterior insular gyri, whereas those for language sites included posterior superior temporal, posterior middle temporal, inferior frontal, supramarginal, and angular gyri.

CONCLUSIONS

Multimodal data suggests that TTG+ may participate in auditory-motor integration.

SIGNIFICANCE

TTG+ likely participates in facial expressions in response to emotional cues during an auditory discourse.

Perception of robotic actions and the influence of gender

In our society interaction with robots is becoming more and more frequent since robots are not only used in the industry, but increasingly often in assistance and in health system. Perception of robots and their movements is crucial for their acceptance. Here we shortly review basic mechanisms of perception of actions, and then of perception of robotic and human movements. The literature demonstrates that there are commonalities, but also differences in the perception of human and robotic movements. Especially interesting are biologic gender differences in the perception of robotic movements. The results show that males seem to be more sensitive to the differences between robotic and anthropomorphic movements, whereas females seem not to perceive such differences. However, females transfer more anthropomorphic features to robotic movements. While looking at the brain activation during perception of humanoid and robotic movements in different genders one can conclude that different strategies are used; female seem to analyse robotic movements online, while male seem to use previous knowledge from interaction with robots. Further research is needed to specify more such gender differences.

Theory of mind and executive dysfunction in chronic inflammatory demyelinating polyneuropathy

BACKGROUND AND PURPOSE

Although chronic inflammatory demyelinating polyneuropathy (CIDP) is understood as a disease affecting the peripheral nervous system, mild cognitive dysfunction, particularly in the executive domain, has been described to form part of the condition. Here our interest lay in CIDP-related theory of mind (ToM) capacities as an aspect of social cognition relevant for many aspects of everyday life.

METHODS

Twenty-nine patients with CIDP and 23 healthy controls participated in this study. They were subjected to overview cognitive testing, different executive function (EF) tasks, as well as to the Faux Pas Recognition Task (FPRT) for assessing cognitive ToM and the Reading the Mind in the Eyes Test (RMET) with respect to affective ToM.

RESULTS

Persons with CIDP and controls did not differ with respect to their overall cognitive state. However, in the German verbal fluency standard, the digit span forward and the digit span backward tests used as EF tasks patients performed significantly worse than controls. Further, performance was abnormally low in the FPRT, whilst the groups did not differ with respect to RMET results. The FPRT and digit span backward results correlated with each other.

CONCLUSIONS

Patients with CIDP showed deficits in cognitive ToM performance together with EF dysfunction, whilst affective ToM was preserved. Altogether, the results suggest that low cognitive ToM capacities in patients with CIDP arise as a particular aspect of disease-related executive dysfunction.

Facilitation of imitative movement in patients with chronic hemiplegia triggered by illusory ownership

The sense of body ownership, the feeling that one's body belongs to oneself, is a crucial subjective conscious experience of one's body. Recent methodological advances regarding crossmodal illusions have provided novel insights into how multisensory interactions shape human perception and cognition, underpinning conscious experience, particularly alteration of body ownership. Moreover, in post-stroke rehabilitation, encouraging the use of the paretic limb in daily life is considered vital, as a settled sense of ownership and attentional engagement toward the paralyzed body part may promote increased frequency of its use and prevent learned nonuse. Therefore, in addition to traditional methods, novel interventions using neurorehabilitation techniques that induce self-body recognition are needed. This study investigated whether the illusory experience of a patient's ownership alterations of their paretic hand facilitates the enhancement in the range of motion of succeeding imitation movements. An experiment combining a modified version of the rubber hand illusion with imitation training was conducted with chronic hemiplegia. A larger imitation movement of the paretic hand was observed in the illusion-induced condition, indicating that the feeling of ownership toward the observed limb promotes the induction of intrinsic potential for motor performance. This training, using subjective experience, may help develop new post-stroke rehabilitation interventions.

The evolution of hierarchically structured communication

Human language sentences are standardly understood as exhibiting considerable hierarchical structure: they can and typically do contain parts that in turn contain parts, etc. In other words, sentences are thought to generally exhibit significant nested part-whole structure. As far as we can tell, this is not a feature of the gestural or vocal communication systems of our great ape relatives. So, one of the many challenges we face in providing a theory of human language evolution is to explain the evolution of hierarchically structured communication in our line. This article takes up that challenge. More specifically, I first present and motivate an account of hierarchical structure in language that departs significantly from the orthodox conception of such structure in linguistics and evolutionary discussions that draw on linguistic theory. On the account I propose, linguistic structure, including hierarchical structure, is treated as a special case of structured action. This account is rooted in the cognitive neuroscience of action, as opposed to (formal) linguistic theory. Among other things, such an account enables us to see how selection for enhanced capacities of act organization and act control in actors, and for act interpretation in observers, might have constructed the brain machinery necessary for the elaborate forms of hierarchically structured communication that we humans engage in. I flesh out this line of thought, emphasizing in particular the role of hominin technique and technology, and the social learning thereof, as evolutionary drivers of this brain machinery.

Kicking in or kicking out? The role of the individual motor expertise in predicting the outcome of rugby actions

In sports, understanding others' actions represents a fundamental skill that allows players to predict the outcome of teammates' and opponents' actions and counteract them properly. While it is well known that motor expertise sets better premises for predicting the result of an observed sports action, it remains untested whether this principle applies to a team where players cover different positions that imply different motor repertoires. To test this hypothesis, we selected rugby as a paradigmatic example in which only one or two players out of 22 train and perform placed kicks. We administered a placed kick outcome prediction task to three groups of participants, namely, rugby kickers, rugby non-kickers, and controls, thus spanning over different combinations of motor expertise and visual experience. Kickers outperformed both their non-kicking teammates and controls in overall prediction accuracy. We documented how the viewpoint of observation, the expertise of the observed kicker, and the position of the kick on the court influenced the prediction performance across the three groups. Finally, we revealed that within rugby players, the degree of motor expertise (but not the visual experience) causally affects accuracy, and such a result stands even after accounting for the level of visual experience. These findings extend the role of motor expertise in decoding and predicting others' behaviors to sports teammates, among which every member is equipped with a position-specific motor repertoire, advocating for new motor training procedures combining the gestures to-be-performed with those to-be-faced.

Improving Swallowing Function and Ability in Post Stroke Dysphagia: A Randomized Clinical Trial

Post-stroke dysphagia is a prevalent, life threatening condition. Scientists recommended implementing behavioral therapies with new technologies such as transcranial direct current of stimulation (TDCS). Studies showed promising TDCS effects, and scientists suggested the investigation of the effectiveness of different montages. Supramarginal gyrus (SMG) is important in swallowing function. Our study aimed to investigate the effectiveness of stimulating SMG in improving post-stroke dysphagia. Forty-four patients finished the study (a randomized, double-blind one). All of them received behavioral therapy. The real group received anodal (2 mA, 20 min) stimulation on the intact SMG, and the sham group received the same for 30 s (5 sessions). Patients were assessed with Functional Oral Intake Scale (FOIS) and Mann Assessment of Swallowing Ability (MASA) after treatment and at one-month follow-up. The results showed that the difference between groups at baseline was not significant. According to MASA both groups improved significantly during the time (p-value < 0.001). The improvement in the real group was significantly higher than in the sham group after treatment (p-value = 0.002) and after one-month follow-up (p-value < 0.001). According to FOIS, most of the patients in the real group (72.70%) reached level 6 or 7 after one-month follow-up which was significantly higher than the sham group (31.80%, p-value = 0.007). In conclusion, TDCS applied to the scalp's surface associated with SMG localization may improve swallowing function in the stroke patients with dysphagia.

"The clothes (and the face) make the Starman": Facial and clothing features shape self-other matching processes between human observers and a cartoon character

Anthropomorphization occurs when human characteristics are attributed to nonhuman animals or objects. One process that could facilitate the anthropomorphization of nonhuman animals may be a self-other body-part matching mechanism wherein the body of the nonhuman animal is conceptually mapped to the human observer's representation of their body. The present study was designed to determine if specific features could facilitate body-part matching between the cartoon of a nonhuman animal and human observers. Participants responded to targets presented on the cartoon of a starfish. In No Structure conditions, dots and curved lines were distributed evenly within the starfish. In Face conditions, two dots and one curved line represented eyes and a mouth of a "face". In Clothes conditions, dots and lines represented a shirt and pants. Body-part matching emerged when the image had a face or clothing, but did not emerge in No Structure conditions. These studies provide unique evidence that the anthropomorphization of a nonhuman cartoon may be facilitated by human-like internal features on the image.

Eylem Gözlem Terapisi ile Unilateral Serebral Palsili Çocuklarda Üst Ekstremite Fonksiyonelliğinin Geliştirilmesi

Eylem Gözlem Terapisi (EGT) hareketlerin izlenmesi sonrası aynı hareketlerin taklit edilmesi ile merkezi sinir sistemi restorasyonunu destekleyen nörorehabilitasyon temelli bir tedavi yaklaşımıdır. Serebral palsi, parkinson, inme, ortopedik yaralanmalar, alzheimer ve konuşma bozuklukları gibi pek çok hastalıkta, fonksiyonu gerçekleştiren nöral yapıları aktive etmek için nörofizyolojik mekanizmadan yararlanan yeni bir rehabilitasyon yaklaşımı olarak bilinir. Sağlıklı bireylerde ve nörolojik veya ortopedik etkilenimi olan bireylerde yapılan araştırmalar; EGT uygulamasının gözlemcinin motor sisteminde kolaylaştırmayı indüklediği ve eylem-algı eşleştirme mekanizmasını desteklediği bilinir. Bu derleme, Serebral Palsi (SP) tanılı çocuklarda üst ekstremiteye yönelik uygulanan EGT programlarının kullanımı ve etkinliği ile ilgili mevcut bilgileri gözden geçirmek amacıyla planlanmıştır. EGT kullanımının farklı koşullara kolayca adapte edilebilmesi, nöral plasitisiteyi destekleyerek motor öğrenmeyi fasilite etmesi ve ekonomik olması nedeniyle, SP’li çocukların üst ekstremite rehabilitasyonunda kullanımının uygun olduğu; ancak protokol, süre ve uygulama şekli açısından optimal uygulama prensiplerinin belirlenebilmesi için daha detaylı çalışmalara ihtiyaç olduğu düşünülmektedir.

Imitative and contagious behaviors in animals and their potential roles in the study of neurodevelopmental disorders

Social learning in the forms of imitative and contagious behaviors are essential for learning abilities and social interaction. However, children with neurodevelopmental disorders and intellectual disabilities show impairments in these behaviors, which profoundly affect their communication skills and cognitive functions. Although these deficits are well studied in humans, pre-clinical animal model assessments of imitative and contagious behavioral deficits are limited. Here, we first define various forms of social learning as well as their developmental and evolutionary significance in humans. We also explore the impact of imitative and contagious behavioral deficits in several neurodevelopmental disorders associated with autistic-like symptoms. Second, we highlight imitative and contagious behaviors observed in nonhuman primates and other social animals commonly used as models for neurodevelopmental disorders. Lastly, we conceptualize these behaviors in the contexts of mirror neuron activity, learning, and empathy, which are highly debated topics. Taken together, this review furthers the understanding of imitative and contagious behaviors. We hope to prompt and guide future behavioral studies in animal models of neurodevelopmental disorders.

Tracing embodied word production in persons with Parkinson's disease in distinct motor conditions

Embodied cognition theories posit direct interactions between sensorimotor and mental processing. Various clinical observations have been interpreted in this controversial framework, amongst others, low verb generation in word production tasks performed by persons with Parkinson's disease (PD). If this were the consequence of reduced motor simulation of prevalent action semantics in this word class, reduced PD pathophysiology should result in increased verb production and a general shift of lexical contents towards particular movement-related meanings. 17 persons with PD and bilateral deep brain stimulation (DBS) of the subhtalamic nucleus (STN) and 17 healthy control persons engaged in a semantically unconstrained, phonemic verbal fluency task, the former in both DBS-off and DBS-on states. The analysis referred to the number of words produced, verb use, and the occurrence of different dimensions of movement-related semantics in the lexical output. Persons with PD produced fewer words than controls. In the DBS-off, but not in the DBS-on condition, the proportion of verbs within this reduced output was lower than in controls. Lowered verb production went in parallel with a semantic shift: in persons with PD in the DBS-off, but not the DBS-on condition, the relatedness of produced words to own body-movement was lower than in controls. In persons with PD, DBS induced-changes of the motor condition appear to go along with formal and semantic shifts in word production. The results are compatible with the idea of some impact of motor system states on lexical processing.

Trainability of novel person recognition based on brief exposure to form and motion cues

Fast and accurate recognition of teammates is crucial in contexts as varied as fast-moving sports, the military, and law enforcement engagements; misrecognition can result in lost scoring opportunities in sport or friendly fire in combat contexts. Initial studies on teammate recognition in sport suggests that athletes are adept at this perceptual ability but still susceptible to errors. The purpose of the current proof-of-concept study was to explore the trainability of teammate recognition from very brief exposure to vision of the whole-body form and motion of a previously unknown individual. Participants were divided into three groups: a 4-week training group who were also the actors for the test and training footage, a 2-week training group, and a no-training group. Findings revealed significant differences between the training groups and their improvement from the pre-to post-test on Response Accuracy and Movement Time. The current study found the best performance in the 4-week Training group. The biggest improvement was found in the 2-week training group, whilst no significant improvement was made in the Control group. These results suggest that training was effective, but also indicate that having initially performed the movements as actors may have led to improvements in baseline testing and ultimately the best results, thus physical performance of skills combined with video-based training may reduce the amount of time needed to improve teammate identification.

Two modes of being together: The levels of intersubjectivity and human relatedness in neuroscience and psychoanalytic thinking

The notion of intersubjectivity has achieved a primary status in contemporary psychoanalytic debate, stimulating new theoretical proposals as well as controversies. This paper presents an overview of the main contributions on inter-subjectivity in the field of neurosciences. In humans as well as-probably-in other species, the ability for emotional resonance is guaranteed early in development. Based on this capacity, a primary sense of connectedness is established that can be defined inter-subjective in that it entails sharing affective states and intentions with caregivers. We propose to define such a form of inter-subjectivity as contingent, since the infant's early abilities for resonance do not imply the more generalized capacity to permanently conceive of the relationship outside the realm of current interactions and the infant-caregiver's mutual correspondence of internal states. This form of connection, hence, results in a self-referential, bodily, and affectively codified, context- and time dependent, like-me experience of interactions. The gradual maturation of brain structures and processes as well as interactive experiences allow proper intersubjectivity exchanges, grounded on new intentional and representational capacities, to evolve. In this more mature form of intersubjectivity, the individual is allowed to conceive of her own psychic space both as distinct and as possibly connected with the other's contents and experience, even in the absence of current behavioral indicators of such correspondence. This multi-layered model of intersubjectivity, which is embraced by current neuroscience research, seems to allow for new interpretations of psychoanalytic models of human relatedness based upon classic clinical observations.

Human-Animal Similarity and the Imageability of Mental State Concepts for Mentalizing Animals

The attribution of mental states (MS) to other species typically follows a scala naturae pattern. However, “simple” mental states, including emotions, sensing, and feelings are attributed to a wider range of animals as compared to the so-called “higher” cognitive abilities. We propose that such attributions are based on the perceptual quality (i.e. imageability) of mental representations related to MS concepts. We hypothesized that the attribution of highly imaginable MS is more dependent on the familiarity of participants with animals when compared to the attribution of MS low in imageability. In addition, we also assessed how animal agreeableness, familiarity with animals, and the type of human-animal interaction related to the judged similarity of animals to humans. Sixty-one participants (19 females, 42 males) with a rural (n = 20) and urban (n = 41) background rated twenty-six wild and domestic animals for their perceived similarity with humans and ability to experience a set of MS: (1) Highly imageable MS: joy, anger, and fear, and (2) MS low in imageability: capacity to plan and deceive. Results show that more agreeable and familiar animals were considered more human-like. Primates, followed by carnivores, suines, ungulates, and rodents were rated more human-like than xenarthrans, birds, arthropods, and reptiles. Higher MS ratings were given to more similar animals and more so if the MS attributed were high in imageability. Familiarity with animals was only relevant for the attribution of the MS high in imageability.

Multiple Roles of Multimodality Among Interacting Agents

The term ‘multimodality’ has come to take on several somewhat different meanings depending on the underlying theoretical paradigms and traditions, and the purpose and context of use. The term is closely related to embodiment, which in turn is also used in several different ways. In this paper, we elaborate on this connection and propose that a pragmatic and pluralistic stance is appropriate for multimodality. We further propose a distinction between first and second order effects of multimodality; what is achieved by multiple modalities in isolation and the opportunities that emerge when several modalities are entangled. This highlights questions regarding ways to cluster or interchange different modalities, for example through redundancy or degeneracy. Apart from discussing multimodality with respect to an individual agent, we further look to more distributed agents and situations where social aspects become relevant.

In robotics, understanding the various uses and interpretations of these terms can prevent miscommunication when designing robots, as well as increase awareness of the underlying theoretical concepts. Given the complexity of the different ways in which multimodality is relevant in social robotics, this can provide the basis for negotiating appropriate meanings of the term at a case by case basis.

Resonance as a Design Strategy for AI and Social Robots

Resonance, a powerful and pervasive phenomenon, appears to play a major role in human interactions. This article investigates the relationship between the physical mechanism of resonance and the human experience of resonance, and considers possibilities for enhancing the experience of resonance within human-robot interactions. We first introduce resonance as a widespread cultural and scientific metaphor. Then, we review the nature of "sympathetic resonance" as a physical mechanism. Following this introduction, the remainder of the article is organized in two parts. In part one, we review the role of resonance (including synchronization and rhythmic entrainment) in human cognition and social interactions. Then, in part two, we review resonance-related phenomena in robotics and artificial intelligence (AI). These two reviews serve as ground for the introduction of a design strategy and combinatorial design space for shaping resonant interactions with robots and AI. We conclude by posing hypotheses and research questions for future empirical studies and discuss a range of ethical and aesthetic issues associated with resonance in human-robot interactions.

Effects of thalamic and basal ganglia deep brain stimulation on language-related functions - Conceptual and clinical considerations

Deep Brain Stimulation (DBS) is a therapy for various neurological movement disorders. It acts predominantly on motor symptoms, but may unfold a number of mostly subtle cognitive effects. In this regard, reports on particular language-related DBS sequels are comparably frequent, but difficult to overlook, given the heterogeneity of targeted structures in the brain, treated diseases, assessment methods and results reported. Accordingly, available knowledge was organized with respect to important aspects, such as the main DBS loci and surgical versus neuromodulatory therapy actions. Current views of biolinguistic underpinnings of the reviewed data, their clinical relevance and potential implications are discussed.

Respiratory function modulated during execution, observation, and imagination of walking via SII

The Mirror Neurons System (MNS) consists of brain areas active during actions execution, as well as observation-imagination of the same actions. MNS represents a potential mechanism by which we understand other's action goals. We investigated MNS activation for legs actions, and its interaction with the autonomic nervous system. We performed a physiological and fMRI investigation on the common neural structures recruited during the execution, observation, and imagination of walking, and their effects on respiratory activity. Bilateral SMA were activated by all three tasks, suggesting that these areas are responsible for the core of the MNS effect for walking. Moreover, we observed in bilateral parietal opercula (OP1, secondary somatosensory cortex-SII) evidence of an MNS subtending walking execution-observation-imagination that also modulated the respiratory function. We suggest that SII, in modulating the vegetative response during motor activity but also during observation-imagination, consists of a re-enacting function which facilitates the understanding of motor actions.

[Mirror neurons, neural substrate of action understanding?]

In 1992, the Laboratory of Human Physiology at the University of Parma (Italy) publish a study describing "mirror" neurons in the macaque that activate both when the monkey performs an action and when it observes an experimenter performing the same action. The research team behind this discovery postulates that the mirror neurons system is the neural basis of our ability to understand the actions of others, through the motor mapping of the observed action on the observer's motor repertory (direct-matching hypothesis). Nevertheless, this conception met serious criticism. These critics attempt to relativize their function by placing them within a network of neurocognitive and sensory interdependencies. In short, the essential characteristic of these neurons is to combine the processing of sensory information, especially visual, with that of motor information. Their elementary function would be to provide a motor simulation of the observed action, based on visual information from it. They can contribute, with other non-mirror areas, to the identification/prediction of the action goal and to the interpretation of the intention of the actor performing it. Studying the connectivity and high frequency synchronizations of the different brain areas involved in action observation would likely provide important information about the dynamic contribution of mirror neurons to "action understanding". The aim of this review is to provide an up-to-date analysis of the scientific evidence related to mirror neurons and their elementary functions, as well as to shed light on the contribution of these neurons to our ability to interpret and understand others' actions.

Pupillometry as a measure of cognitive load in mental rotation tasks with abstract and embodied figures

We investigated sex differences in behavioral performance and cognitive load in chronometric mental rotation tasks with abstract and embodied figures. Eighty participants (44 females and 36 males) completed 126 items, which included cube figures, body postures, and human figures, which were all comparable in shape and color. Reaction time, accuracy, and cognitive load, measured by changes in pupil dilation, were analyzed. As a function of angular disparity, participants showed shorter reaction times and higher accuracy rates for embodied stimuli than cube figures. Changes in pupil dilation showed a similar pattern, indicating that mental rotation of embodied figures caused less cognitive load to solve the task. No sex differences appeared in any of the measurements.

What modulates the Mirror Neuron System during action observation?: Multiple factors involving the action, the actor, the observer, the relationship between actor and observer, and the context

Seeing an agent perform an action typically triggers a motor simulation of that action in the observer's Mirror Neuron System (MNS). Over the past few years, it has become increasingly clear that during action observation the patterns and strengths of responses in the MNS are modulated by multiple factors. The first aim of this paper is therefore to provide the most comprehensive survey to date of these factors. To that end, 22 distinct factors are described, broken down into the following sets: six involving the action; two involving the actor; nine involving the observer; four involving the relationship between actor and observer; and one involving the context. The second aim is to consider the implications of these findings for four prominent theoretical models of the MNS: the Direct Matching Model; the Predictive Coding Model; the Value-Driven Model; and the Associative Model. These assessments suggest that although each model is supported by a wide range of findings, each one is also challenged by other findings and relatively unaffected by still others. Hence, there is now a pressing need for a richer, more inclusive model that is better able to account for all of the modulatory factors that have been identified so far.

Expertise Influences Congruency Monitoring During Action Observation at the Motor Level

Congruency monitoring of action occurs in individuals with relevant motor experience while observing actions. However, it remains unclear whether congruency monitoring can occur at the motor level and the extent to which expertise contributes. Here, we examined the behavioral performance and electrophysiological brain activity of individuals with and without domain-specific expertise when judging the action congruency of occluded video clips of a snowboard halfpipe trick and normal walking. For the halfpipe trick, experts exhibited better task performance and greater midline theta oscillations before possible incongruency compared with controls. Source reconstruction for the theta oscillation revealed a stronger activation in the middle and superior frontal gyrus for experts in response to incongruency compared with controls. Incongruent halfpipe actions elicited a higher N400 amplitude in experts compared with congruent actions, while no such differences were observed in controls. Source reconstruction revealed the activation in the board frontal regions and middle temporal gyrus for experts. These findings suggest that congruency monitoring can occur at the motor level during action observations and is modulated by individual expertise. The modulation of expertise reflects in the special N400 effect and midline theta oscillation.

The Cognitive-Affective-Social Theory of Learning in digital Environments (CASTLE)

For a long time, research on individuals learning in digital environments was primarily based on cognitive-oriented theories. This paper aims at providing evidence that social processes affect individual learning with digital materials. Based on these theories and empirical results, a social-processes-augmented theory is suggested: the Cognitive-Affective-Social Theory of Learning in digital Environments (CASTLE). This CASTLE postulates that social cues in digital materials activate social schemata in learners leading to enhanced (para-)social, motivational, emotional, and metacognitive processes. To substantiate this theory, socio-cognitive theories are used, which predict social influences on learning with digital materials. Besides, previous empirical findings are presented assuming that with a rising number of social cues in digital materials, the influence of social processes increases. Finally, consequences regarding the design of digital learning media are discussed.

The Potential Role of Dopamine in Mediating Motor Function and Interpersonal Synchrony

Motor functions in general and motor planning in particular are crucial for our ability to synchronize our movements with those of others. To date, these co-occurring functions have been studied separately, and as yet it is unclear whether they share a common biological mechanism. Here, we synthesize disparate recent findings on motor functioning and interpersonal synchrony and propose that these two functions share a common neurobiological mechanism and adhere to the same principles of predictive coding. Critically, we describe the pivotal role of the dopaminergic system in modulating these two distinct functions. We present attention deficit hyperactivity disorder (ADHD) as an example of a disorder that involves the dopaminergic system and describe deficits in motor and interpersonal synchrony. Finally, we suggest possible directions for future studies emphasizing the role of dopamine modulation as a link between social and motor functioning.

Watch and Learn: The Cognitive Neuroscience of Learning from Others' Actions

The mirror neuron system has dominated understanding of observational learning from a cognitive neuroscience perspective. Our review highlights the value of observational learning frameworks that integrate a more diverse and distributed set of cognitive and brain systems, including those implicated in sensorimotor transformations, as well as in more general processes such as executive control, reward, and social cognition. We argue that understanding how observational learning occurs in the real world will require neuroscientific frameworks that consider how visuomotor processes interface with more general aspects of cognition, as well as how learning context and action complexity shape mechanisms supporting learning from watching others.

Increased links between language and motor areas: A proof-of-concept study on resting-state functional connectivity following Personalized Observation, Execution and Mental imagery therapy in chronic aphasia

A tight coupling of language and motor processes has been established, which is consistent with embodied cognition theory. However, very few therapies have been designed to exploit the synergy between motor and language processes to help rehabilitate people with aphasia (PWA). Moreover, the underlying mechanisms supporting the efficacy of such approaches remain unknown. Previous work in our laboratory has demonstrated that personalized observation, execution, and mental imagery therapy (POEM)-a new therapy using three sensorimotor strategies to trigger action verb naming-leads to significant improvements in verb retrieval in PWA. Moreover, these improvements were supported by significant activations in language and sensorimotor processing areas, which further reinforce the role of both processes in language recovery (Durand et al., 2018). The present study investigates resting state functional connectivity (rsFC) changes following POEM in a pre-/post-POEM therapy design. A whole brain network functional connectivity approach was used to assess and describe changes in rsFC in a group of four PWA, who were matched and compared with four healthy controls (HC). Results showed increased rsFC in PWA within and between visuo-motor and language areas (right cuneal cortex-left supracalcarin (SCC) cortex/right precentral gyrus (PreCG)-left lingual gyrus (LG)) and between areas involved in action processing (right anterior parahippocampal gyrus (aPaHC)-left superior parietal lobule (SPL). In comparison to HC, the PWA group showed increased rsFC between the right inferior frontal gyrus (IFG) and left thalamus, which are areas involved in lexico-semantic processing. This proof-of-concept study suggests that the sensorimotor and language strategies used in POEM may induce modifications in large-scale networks, probably derived from the integration of visual and sensorimotor systems to sustain action naming, which is consistent with the embodied cognition theory.

Are They Really Trying to Save Their Buddy? The Anthropomorphism of Animal Epimeletic Behaviours

Simple Summary

Anthropomorphism, defined as attributing human traits to animals and other entities, seems to have appeared during evolution to improve an individual’s understanding of other species (or indeed the world in general). Yet anthropomorphism can have beneficial or harmful consequences especially for animals, and there seems to be little interest in monitoring the potential danger of this approach. Few studies have focused on the factors affecting how we attribute intentions or beliefs to animals, and more quantitative studies are needed to identify how and why humans attribute mental states and cognitive abilities to other animals. In this study, participants answer questions about three videos in which an individual (a sparrow, an elephant and a macaque, respectively) displayed behaviours towards an inanimate conspecific that suddenly regained consciousness at the end of the footage. A fourth video showed a robot dog being kicked by an engineer to demonstrate its stability. These questions were designed to measure how far participants attribute humanlike intentions, beliefs or mental states to non-human animals and robots. Men and older participants are less likely to attribute humanlike mental states to animals. Similarly, people who work with animals or have at least one pet at home demonstrated less naïve anthropomorphism. Conversely, we found that members of animal protection associations showed more biophilia (affinity for other living organisms), attributed more intentions and mental states to animals and were further from biological reality (current scientific knowledge of each species) than non-members. Understanding the potential usefulness of these factors can lead to better relationships with animals and encourage human-robot interactions.

Abstract

Anthropomorphism is a natural tendency in humans, but it is also influenced by many characteristics of the observer (the human) and the observed entity (here, the animal species). This study asked participants to complete an online questionnaire about three videos showing epimeletic behaviours in three animal species. In the videos, an individual (a sparrow, an elephant and a macaque, respectively) displayed behaviours towards an inanimate conspecific that suddenly regained consciousness at the end of the footage. A fourth video showed a robot dog being kicked by an engineer to demonstrate its stability. Each video was followed by a series of questions designed to evaluate the degree of anthropomorphism of participants, from mentaphobia (no attribution of intentions and beliefs, whatever the animal species) to full anthropomorphism (full attribution of intentions and beliefs by animals, to the same extent as in humans) and to measure how far the participants had correctly assessed each situation in terms of biological reality (current scientific knowledge of each species). There is a negative correlation (about 61%) between the mental states attributed to animals by humans and the real capability of animals. The heterogeneity of responses proved that humans display different forms of anthropomorphism, from rejecting all emotional or intentional states in animals to considering animals to show the same intentions as humans. However, the scores participants attributed to animals differed according to the species shown in the video and to human socio-demographic characteristics. Understanding the potential usefulness of these factors can lead to better relationships with animals and encourage a positive view of human-robot interactions. Indeed, reflective or critical anthropomorphism can increase our humanity.

Experience has a limited effect on humans' ability to predict the outcome of social interactions in children, dogs and macaques

The ability to predict others' behaviour represents a crucial mechanism which allows individuals to react faster and more appropriately. To date, several studies have investigated humans' ability to predict conspecifics' behaviour, but little is known on our ability to predict behaviour in other species. Here, we aimed to test humans' ability to predict social behaviour in dogs, macaques and humans, and assess the role played by experience and evolution on the emergence of this ability. For this purpose, we presented participants with short videoclips of real-life social interactions in dog, child and macaque dyads, and then asked them to predict the outcome of the observed interactions (i.e. aggressive, neutral or playful). Participants were selected according to their previous species-specific experience with dogs, children and non-human primates. Our results showed a limited effect of experience on the ability to predict the outcome of social interactions, which was mainly restricted to macaques. Moreover, we found no support to the co-domestication hypothesis, in that participants were not especially skilled at predicting dog behaviour. Finally, aggressive outcomes in dogs were predicted significantly worse than playful or neutral ones. Based on our findings, we suggest possible lines for future research, like the inclusion of other primate species and the assessment of cultural factors on the ability to predict behaviour across species.

Implicit visual sensitivity towards slim versus overweight bodies modulates motor resonance in the primary motor cortex: A tDCS study

Motor resonance (MR) can be influenced by individual differences and similarity in the physical appearance between the actor and observer. Recently, we reported that action simulation is modulated by an implicit visual sensitivity towards normal-weight compared with overweight bodies. Furthermore, recent research has suggested the existence of an action observation network responsible for MR, with limited evidence whether the primary motor cortex (M1) is part of this. We expanded our previous findings with regards to the role of an implicit normal-weight-body preference in the MR mechanism. At the same time, we tested the functional relevance of M1 to MR, by using a transcranial direct current stimulation (tDCS) protocol. Seventeen normal-weight and 17 overweight participants were asked to observe normal-weight or overweight actors reaching and grasping a light or heavy cube, and then, at the end of each video-clip to indicate the correct cube weight. Before the task, all participants received 15 min of sham or cathodal tDCS over the left M1. Measures of anti-fat attitudes were also collected. During sham tDCS, all participants were better in simulating the actions performed by normal-weight compared with overweight models. Surprisingly, cathodal tDCS selectively improved the ability in the overweight group to simulate actions performed by the overweight models. This effect was not associated with scores of fat phobic attitudes or implicit anti-fat bias. Our findings are discussed in the context of relevance of M1 to MR and its social modulation by anti-fat attitudes.

Increased pSTS activity and decreased pSTS-mPFC connectivity when processing negative social interactions

We have previously shown that activity and connectivity within and between the action observation and mentalizing brain systems reflect the degree of positive dimensions expressed by social interactions such as cooperativity and affectivity, respectively. Here we aim to extend this evidence by investigating the neural bases of processing negative dimensions of observed interactions, such as competition and affective conflict, possibly representing a benchmark for different pathological conditions. In this fMRI study 34 healthy participants were shown pictures depicting interactions characterized by two crossed dimensions, i.e. positively- vs. negatively- connotated social intentions mainly expressed in terms of motor acts vs. mental states, i.e. cooperative, competitive, affective and conflicting interactions. We confirmed the involvement of the action observation and mentalizing networks in processing intentions mainly expressed through motor acts (cooperative/competitive) vs. mental states (affective/conflicting), respectively. Results highlighted the selective role of the left pSTS/TPJ in decoding social interactions, even when compared with parallel actions by non-interacting individuals. Its right-hemispheric homologue displayed stronger responses to negative than positive social intentions, regardless of their motor/mental status, and decreased connectivity with the medial prefrontal cortex (mPFC) when processing negative interactions. The resulting mPFC downregulation by negative social scenes might reflect an adaptive response to socio-affective threats, via decreased mentalizing when facing negative social stimuli. This evidence on the brain mechanisms underlying the decoding of real complex interactions represents a baseline for assessing both the neural correlates of impaired social cognition, and the effects of rehabilitative treatments, in neuro-psychiatric diseases or borderline conditions such as loneliness.

Are There Differences in Experts' and Lay Assessors' Attractiveness Judgments of Non-Professional Men's Dance/Gait Movements?

Research on attractiveness assessments of men's dance has shown that raters derive and integrate information about male mating-related qualities into their attractiveness assessments, but prior studies have focused on lay assessors (i.e., individuals with no professional dance background) rather than dance experts. We recruited male and female Russian dance experts (n = 23) to judge gender-neutral, featureless virtual characters, animated with motion-captured dance movements and gaits of British men, and compared their dance assessments to those from a group of Russian male and female lay assessors (n = 73). The dance experts provided higher dance and gait attractiveness judgments than the lay assessors. Both groups judged the gait movements to be of higher attractiveness than the dance movements. Differences in attractiveness assessments between experts and lay assessors were larger for the male judges than for the female judges. In an additional survey, the dance experts (versus lay assessors) placed greater emphasis on the importance of dance-related capacities and skills. We discuss our findings with reference to past research on dance/gait attractiveness as assessed by lay judges and the role of expertise in assessing body movement.

Comparative Brain Imaging Reveals Analogous and Divergent Patterns of Species and Face Sensitivity in Humans and Dogs

Conspecific-preference in social perception is evident for multiple sensory modalities and in many species. There is also a dedicated neural network for face processing in primates. However, the evolutionary origin and the relative role of neural species sensitivity and face sensitivity in visuo-social processing are largely unknown.

Conspecific-preference in social perception is evident for multiple sensory modalities and in many species. There is also a dedicated neural network for face processing in primates. However, the evolutionary origin and the relative role of neural species sensitivity and face sensitivity in visuo-social processing are largely unknown. In this comparative study, species sensitivity and face sensitivity to identical visual stimuli (videos of human and dog faces and occiputs) were examined using functional magnetic resonance imaging in dogs (n = 20; 45% female) and humans (n = 30; 50% female). In dogs, the bilateral mid suprasylvian gyrus showed conspecific-preference, no regions exhibited face-preference, and the majority of the visually-responsive cortex showed greater conspecific-preference than face-preference. In humans, conspecific-preferring regions (the right amygdala/hippocampus and the posterior superior temporal sulcus) also showed face-preference, and much of the visually-responsive cortex showed greater face-preference than conspecific-preference. Multivariate pattern analyses (MVPAs) identified species-sensitive regions in both species, but face-sensitive regions only in humans. Across-species representational similarity analyses (RSAs) revealed stronger correspondence between dog and human response patterns for distinguishing conspecific from heterospecific faces than other contrasts. Results unveil functional analogies in dog and human visuo-social processing of conspecificity but suggest that cortical specialization for face perception may not be ubiquitous across mammals.

SIGNIFICANCE STATEMENT To explore the evolutionary origins of human face-preference and its relationship to conspecific-preference, we conducted the first comparative and noninvasive visual neuroimaging study of a non-primate and a primate species, dogs and humans. Conspecific-preferring brain regions were observed in both species, but face-preferring brain regions were observed only in humans. In dogs, an overwhelming majority of visually-responsive cortex exhibited greater conspecific-preference than face-preference, whereas in humans, much of the visually-responsive cortex showed greater face-preference than conspecific-preference. Together, these findings unveil functional analogies and differences in the organizing principles of visuo-social processing across two phylogenetically distant mammal species.

Developmental trajectory of interpersonal motor alignment: Positive social effects and link to social cognition

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Interpersonal motor alignment (IMA) has positive effects on healthy social life.

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IMA - mimicry, synchrony, automatic imitation - is studied throughout development.

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It relies on motor resonance brain mechanisms identified throughout development.

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It is modulated by contextual and personal factors.

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IMA is underinvestigated in adolescence, yet it may aid to enhance resilience.

Interpersonal motor alignment is a ubiquitous behavior in daily social life. It is a building block for higher social cognition, including empathy and mentalizing and promotes positive social effects. It can be observed as mimicry, synchrony and automatic imitation, to name a few. These phenomena rely on motor resonance processes, i.e., a direct link between the perception of an action and its execution. While a considerable literature debates its underlying mechanisms and measurement methods, the question of how motor alignment comes about and changes in ontogeny all the way until adulthood, is rarely discussed specifically. In this review we will focus on the link between interpersonal motor alignment, positive social effects and social cognition in infants, children, and adolescents, demonstrating that this link is present early on in development. Yet, in reviewing the existing literature pertaining to social psychology and developmental social cognitive neuroscience, we identify a knowledge gap regarding the healthy developmental changes in interpersonal motor alignment especially in adolescence.

Conversational Therapy through Semi-Immersive Virtual Reality Environments for Language Recovery and Psychological Well-Being in Post Stroke Aphasia

Aphasia is a highly disabling acquired language disorder generally caused by a left-lateralized brain damage. Even if traditional therapies have been shown to induce an adequate clinical improvement, a large percentage of patients are left with some degree of language impairments. Therefore, new approaches to common speech therapies are urgently needed in order to maximize the recovery from aphasia. The recent application of virtual reality (VR) to aphasia rehabilitation has already evidenced its usefulness in promoting a more pragmatically oriented treatment than conventional therapies (CT). In the present study, thirty-six chronic persons with aphasia (PWA) were randomly assigned to two groups. The VR group underwent conversational therapy during VR everyday life setting observation, while the control group was trained in a conventional setting without VR support. All patients were extensively tested through a neuropsychological battery which included not only measures for language skills and communication efficacy but also self-esteem and quality of life questionnairies. All patients were trained through a conversational approach by a speech therapist twice a week for six months (total 48 sessions). After the treatment, no significant differences among groups were found in the different measures. However, the amount of improvement in the different areas was distributed over far more cognitive and psychological aspects in the VR group than in the control group. Indeed, the within-group comparisons showed a significant enhancement in different language tasks (i.e., oral comprehension, repetition, and written language) only in the VR group. Significant gains, after the treatment, were also found, in the VR group, in different psychological dimensions (i.e., self-esteem and emotional and mood state). Given the importance of these aspects for aphasia recovery, we believe that our results add to previous evidence which points to the ecological validity and feasibility of VR treatment for language recovery and psychosocial well-being.

Muscular effort coding in action representation in ballet dancers and controls: Electrophysiological evidence

The present electrophysiological (EEG) study investigated the neural correlates of perceiving effortful vs. effortless movements belonging to a specific repertoire (ballet). Previous evidence has shown an increased heart and respiratory rate during the observation and imagination of human actions that require a great muscular effort. In addition, TMS (transcranial magnetic stimulation) and EEG studies have evidenced a greater muscle-specific cortical excitability and an increase in late event-related potentials during the observation of effortful actions. In this investigation, fifteen professional female ballet dancers and 15 controls with no experience whatsoever with dance, gymnastics, or martial arts were recruited. They were shown 326 short videos displaying a male dancer performing standard ballet steps that could be either effortful or relatively effortless. Participants were instructed to observe each clip and imagine themselves physically executing the same movement. Importantly, they were blinded to the stimuli properties. The observation of effortful compared with effortless movements resulted in a larger P300 over frontal sites in dancers only, likely because of their visuomotor expertise with the specific steps. Moreover, an enhanced Late Positivity was identified over posterior sites in response to effortful stimuli in both groups, possibly reflecting the processing of larger quantities of visual kinematic information. The source reconstruction swLORETA performed on the Late Positivity component showed greater engagement of frontoparietal regions in dancers, while task-related frontal and occipitotemporal visual regions were more active in controls. It, therefore, appears that, in dancers, effort information was encoded in a more refined manner during action observation and in the absence of explicit instruction. Acquired motor knowledge seems to result in visuomotor resonance processes, which, in turn, underlies enhanced action representation of the observed movements.

Action observation treatment improves gait ability in subacute to convalescent stroke patients

The aim of this study was to investigate the effects of action observation treatment (AOT) on gait ability in patients with subacute to convalescent stroke. Sixteen patients with subacute stroke were divided into a control group (n = 8) and AOT group (n = 8) when admitted to the convalescent ward. The control group received a conventional rehabilitation only. In addition to conventional rehabilitation, the AOT received AOT for 3 months (30 min per day 5 times per week). The AOT involved observing the action of another subject in a comfortable gait situation from the front, sides, and back via video and conducting the actual action. All participants were assessed during the main-assessment period, which included a baseline (i.e., when admitted to the convalescent ward) and 1, 2, and 3 months after baseline. The sub-assessment period at 2 and 3 months after baseline was conducted with participants who could walk independently. The main outcomes of the main-assessment and sub-assessment periods were Functional Ambulation Classification (FAC) and the 10-m walk test (10MWT), respectively. With respect to the FAC, we used a split plot design analysis of covariance to test the interaction between assessment time and group. There was no significant interaction between assessment time and group in FAC. However, a significant improvement of the 10MWT in the sub-assessment period was observed in the AOT group, but not the control group. Our results indicate that AOT may be an effective therapy for patients with subacute to convalescent stroke who can walk independently.

The Effects of Instruction Manipulation on Motor Performance Following Action Observation

The effects of action observation (AO) on motor performance can be modulated by instruction. The effects of two top-down aspects of the instruction on motor performance have not been fully resolved: those related to attention to the observed task and the incorporation of motor imagery (MI) during AO. In addition, the immediate vs. 24-h retention test effects of those instruction’s aspects are yet to be elucidated. Forty-eight healthy subjects were randomly instructed to: (1) observe reaching movement (RM) sequences toward five lighted units with the intention of reproducing the same sequence as fast and as accurate as possible (Intentional + Attentional group; AO+At); (2) observe the RMs sequence with the intention of reproducing the same sequence as fast and as accurate as possible and simultaneously to the observation to imagine performing the RMs (Intentional + attentional + MI group; AO+At+MI); and (3) observe the RMs sequence (Passive AO group). Subjects’ performance was tested before and immediately after the AO and retested after 24 h. During each of the pretest, posttest, and retest, the subject performed RMs toward the units that were activated in the same order as the observed sequence. Occasionally, the sequence order was changed by beginning the sequence with a different activated unit. The outcome measures were: averaged response time of the RMs during the sequences, difference between the response time of the unexpected and expected RMs and percent of failures to reach the target within 1 s. The averaged response time and the difference between the response time of the unexpected and expected RMs were improved in all groups at posttest compared to pretest, regardless of instruction. Averaged response time was improved in the retest compared to the posttest only in the Passive AO group. The percent of failures across groups was higher in pretest compared to retest. Our findings suggest that manipulating top-down aspects of instruction by adding attention and MI to AO in an RM sequence task does not improve subsequent performance more than passive observation. Off-line learning of the sequence in the retention test was improved in comparison to posttest following passive observation only.

Observer-Agent Kinematic Similarity Facilitates Action Intention Decoding

It is well known that the kinematics of an action is modulated by the underlying motor intention. In turn, kinematics serves as a cue also during action observation, providing hints about the intention of the observed action. However, an open question is whether decoding others’ intentions on the basis of their kinematics depends solely on how much the kinematics varies across different actions, or rather it is also influenced by its similarity with the observer motor repertoire. The execution of reach-to-grasp and place actions, differing for target size and context, was recorded in terms of upper-limb kinematics in 21 volunteers and in an actor. Volunteers had later to observe the sole reach-to-grasp phase of the actor’s actions, and predict the underlying intention. The potential benefit of the kinematic actor-participant similarity for recognition accuracy was evaluated. In execution, both target size and context modulated specific kinematic parameters. More importantly, although participants performed above chance in intention recognition, the similarity of motor patterns positively correlated with recognition accuracy. Overall, these data indicate that kinematic similarity exerts a facilitative role in intention recognition, providing further support to the view of action intention recognition as a visuo-motor process grounded in motor resonance.

Motor activation is modulated by visual experience during cyclic gait observation: A transcranial magnetic stimulation study

Transcranial magnetic stimulation (TMS) has been widely utilized to noninvasively explore the motor system during the observation of human movement. However, few studies have characterized motor cortex activity during periodic gait observation. Thus, this study examined the effects of an observer's visual experience and/or intention to imitate on corticospinal excitability during the observation of another's gait. Twenty-six healthy volunteers were included in this study and allocated to two different groups. Participants in the visual experience group had formal experience with gait observation (physical therapist training), while those in the control group did not. Motor-evoked potentials induced by TMS in the tibialis anterior and soleus muscles were measured as surrogates of corticospinal excitability. Participants were seated and, while resting, they observed a demonstrator's gait or observed it with the intention to subsequently reproduce it. Compared with the resting state, cyclic gait observation led to significant corticospinal facilitation in the tibialis anterior and soleus muscles. However, this pattern of corticospinal facilitation in the measured muscles was not coupled to the pattern of crural muscle activity during actual gait and was independent of the step cycle. This motor cortex facilitation effect during gait observation was enhanced by the observer's visual experience in a manner that was not step cycle-dependent, while the observer's intent to imitate did not affect corticospinal excitatory input to either muscle. In addition, visual experience did not modulate corticospinal excitability in gait-related crural muscles. Our findings indicate that motor cortex activity during gait observation is not in line with the timing of muscle activity during gait execution and is modulated by an individual's gait observation experience. These results suggest that visual experience acquired from repetitive gait observation may facilitate the motor system's control on bipedal walking, but may not promote the learning of muscle activity patterns.

Looking at ancillary systems for verb recovery: Evidence from non-invasive brain stimulation

Several behavioural and neuroimaging studies have suggested that the language function is not restricted into the left areas but it involves regions not predicted by the classical language model. Accordingly, the Embodied Cognition theory postulates a close interaction between the language and the motor system. Indeed, it has been shown that non-invasive brain stimulation (NIBS) is effective for language recovery also when applied over sensorimotor regions, such as the motor cortex, the cerebellum and the spinal cord. We will review a series of NIBS studies in post-stroke aphasic people aimed to assess the impact of NIBS on verb recovery. We first present results which, following the classical assumption of the Broca's area as the key region for verb processing, have shown that the modulation over this area is efficacious for verb improvement. Then, we will present experiments which, according to Embodied Cognition, have directly investigated through NIBS the role of different sensorimotor regions in enhancing verb production. Since verbs play a crucial role for sentence construction which are most often impaired in the aphasic population, we believe that these results have important clinical implications. Indeed, they address the possibility that different structures might support verb processing.

Action Observation and Effector Independency

The finding of reasonably consistent spatial and temporal productions of actions across different body parts has been used to argue in favor of the existence of a high-order representation of motor programs. In these terms, a generalized motor program consists of an abstract memory structure apt to specify a class of non-specific instructions used to guide a broad range of movements (e.g., “grasp,” “bite”). Although a number of studies, using a variety of tasks, have assessed the issue of effector independence in terms of action execution, little is known regarding the issue of effector independence within an action observation context. Here corticospinal excitability (CSE) of the right hand’s first dorsal interosseous (FDI) and abductor digiti minimi (ADM) muscles was assessed by means of single-pulse transcranial magnetic stimulation (spTMS) during observation of a grasping action performed by the hand, the foot, the mouth, the elbow, or the knee. The results indicate that observing a grasping action performed with different body parts activates the effector typically adopted to execute that action, i.e., the hand. We contend that, as far as grasping is concerned, motor activations by action observation are evident in the muscles typically used to perform the observed action, even when the action is executed with another effector. Nevertheless, some exceptions call for a deeper analysis of motor coding.

Physical and observational practices of unusual actions prime action verb processing

Numerous studies have highlighted a strong relationship between language and sensorimotor processes, showing, for example, that perceiving an action influences subsequent language processing. Moreover, previous studies have demonstrated that the context in which actions are perceived is crucial to enable this action-language relationship. In particular, action verb processing is facilitated when an action is perceived in its usual context (e.g., someone watering a plant) but not in an unusual context (e.g., someone watering a computer). This difference could be explained in terms of experience; because people always practice actions in accordance with the context, they have no (visual or motor) experience related to the unusual context. The aim of the present study was to test this assumption by assessing and comparing the effect of physical practice and observational learning on the action-language relationship. The results of two experiments showed a facilitation effect of both training methods. Whereas usual actions systematically prime action verb processing, the link between action and language appears for unusual actions only after training by practicing (experiment 1, physical practice) or observing (experiment 2, observational learning). Overall, these findings support the role of experience in the activation of sensorimotor representations during action verb processing.

Brain activation induced by different strengths of hand grasp: a functional magnetic resonance imaging study

Mirror neuron system can be activated by observation and execution of an action. It has an important function of action understanding. We investigated brain activations in humans by observing the strength of a hand grasp using functional magnetic resonance imaging. Twenty right-handed healthy individuals, consisting of 10 males and 10 females, aged 22.40 ± 2.04 years, were recruited into this study from September to November 2017 via posters. Light hand grasp task video showed a hand lightly grasping and releasing a ball repeatedly. Powerful hand grasp task video showed a hand tightly grasping and releasing a ball repeatedly. Functional magnetic resonance imaging block design paradigm comprised five stimulation blocks alternating with five baseline blocks. Stimulation blocks were presented with two stimulus tasks, consisting of a light grasp and a powerful grasp. Region of interest was defined around the inferior parietal lobule, inferior frontal gyrus, and superior temporal sulcus which have been called mirror neuron system. The inferior parietal lobule, fusiform, postcentral, occipital, temporal, and frontal gyri were activated during light and powerful grasp tasks. The BOLD signal response of a powerful grasp was stronger than that of a light grasp. These results suggest that brain activation of the inferior parietal lobule, which is the core brain region of the mirror neuron system, was stronger in the powerful grasp task than in the light grasp task. We believe that our results might be helpful for instructing rehabilitation of brain injury. This study was approved by the Institutional Review Board of Daegu Oriental Hospital of Daegu Haany University on September 8, 2017 (approval No. DHUMC-D-17020-PRO-01).

Treatment of Medial Medullary Infarction Using a Novel iNems Training: A Case Report and Literature Review

Objective. We describe the case of a 66-year-old Japanese male patient who developed medial medullary infarction along with severe motor paralysis and intense numbness of the left arm, pain catastrophizing, and abnormal physical sensation. We further describe his recovery using a new imagery neurofeedback-based multisensory systems (iNems) training method. Clinical Course and Intervention. The patient underwent physical therapy for the rehabilitation of motor paralysis and numbness of the paralyzed upper limbs; in addition, we implemented iNems training using EEG activity, which aims to synchronize movement intent (motor imagery) with sensory information (feedback visual information). Results. Considerable improvement in motor function, pain catastrophizing, representation of the body in the brain, and abnormal physical sensations was accomplished with iNems training. Furthermore, iNems training improved the neural activity of the default mode network at rest and the sensorimotor region when the movement was intended. Conclusions. The newly developed iNems could prove a novel, useful tool for neurorehabilitation considering that both behavioral and neurophysiological changes were observed in our case.