Switching off: disruptive TMS reveals distinct contributions of the posterior middle temporal gyrus and angular gyrus to bilingual speech production.

The role of the left temporoparietal cortex in speech production has been extensively studied during native language processing, proving crucial in controlled lexico-semantic retrieval under varying cognitive demands. Yet, its role in bilinguals, fluent in both native and second languages, remains poorly understood. Here, we employed continuous theta burst stimulation to disrupt neural activity in the left posterior middle-temporal gyrus (pMTG) and angular gyrus (AG) while Italian-Friulian bilinguals performed a cued picture-naming task. The task involved between-language (naming objects in Italian or Friulian) and within-language blocks (naming objects ["knife"] or associated actions ["cut"] in a single language) in which participants could either maintain (non-switch) or change (switch) instructions based on cues. During within-language blocks, cTBS over the pMTG entailed faster naming for high-demanding switch trials, while cTBS to the AG elicited slower latencies in low-demanding non-switch trials. No cTBS effects were observed in the between-language block. Our findings suggest a causal involvement of the left pMTG and AG in lexico-semantic processing across languages, with distinct contributions to controlled vs. "automatic" retrieval, respectively. However, they do not support the existence of shared control mechanisms within and between language(s) production. Altogether, these results inform neurobiological models of semantic control in bilinguals.

Contextual expectations shape the motor coding of movement kinematics during the prediction of observed actions: A TMS study.

Contextual information may shape motor resonance and support intention understanding during observation of incomplete, ambiguous actions. It is unclear, however, whether this effect is contingent upon kinematics ambiguity or contextual information is continuously integrated with kinematics to predict the overarching action intention. Moreover, a differentiation between the motor mapping of the intention suggested by context or kinematics has not been clearly demonstrated. In a first action execution phase, 29 participants were asked to perform reaching-to-grasp movements towards big or small food objects with the intention to eat or to move; electromyography from the First Dorsal Interosseous (FDI) and Abductor Digiti Minimi (ADM) was recorded. Depending on object size, the intentions to eat or to move were differently implemented by a whole-hand or a precision grip kinematics, thus qualifying an action-muscle dissociation. Then, in a following action prediction task, the same participants were asked to observe an actor performing the same actions and to predict his/her intention while motor resonance was assessed for the same muscles. Of note, videos were interrupted at early or late action phases, and actions were embedded in contexts pointing toward an eating or a moving intention, congruently or incongruently with kinematics. We found greater involvement of the FDI or ADM in the execution of precision or whole-hand grips, respectively. Crucially, this pattern of activation was mirrored during observation of the same actions in congruent contexts, but it was cancelled out or reversed in the incongruent ones, either when videos were interrupted at either early or long phases of action deployment. Our results extend previous evidence by showing that contextual information shapes motor resonance not only under conditions of perceptual uncertainty but also when more informative kinematics is available.

New Insights into the Neuropsychological Profile and Intellectual Quotient Variability in Joubert Syndrome Compared to Other Congenital Cerebellar Malformations.

The neuropsychological characteristics of the cerebellar cognitive affective syndrome (CCAS) in congenital, non-progressive malformations of the cerebellum have been scarcely investigated, and even less is known for Joubert syndrome (JS), an inherited, non-progressive cerebellar ataxia characterized by the so-called molar tooth sign. The few studies on this topic reported inconsistent results about intellectual functioning and specific neuropsychological impairments. The aim of this research is to examine the neuropsychological profile of JS compared to other congenital cerebellar malformations (CM), considering individual variability of intellectual quotient (IQ) in the two groups. Fourteen patients with JS and 15 patients with CM aged 6-25 years were tested through a comprehensive, standardized neuropsychological battery. Their scores in the neuropsychological domains were inspected through descriptive analysis and compared by mean of MANOVA and ANOVA models, then replicated inserting IQ as covariate. The two groups showed a largely overlapping neuropsychological profile, consistent with CCAS. However, the JS group showed worse performance in visual-spatial memory compared to CM patients, although this difference was mitigated when considering IQ. These findings highlight a divergence between JS and other CM in visual-spatial memory, which might suggest a critical role of the cerebellum in recalling task-relevant memories and might inform rehabilitative interventions.

Cerebellar Neurostimulation for Boosting Social and Affective Functions: Implications for the Rehabilitation of Hereditary Ataxia Patients.

Beyond motor deficits, spinocerebellar ataxia (SCA) patients also suffer cognitive decline and show socio-affective difficulties, negatively impacting on their social functioning. The possibility to modulate cerebello-cerebral networks involved in social cognition through cerebellar neurostimulation has opened up potential therapeutic applications for ameliorating social and affective difficulties. The present review offers an overview of the research on cerebellar neurostimulation for the modulation of socio-affective functions in both healthy individuals and different clinical populations, published in the time period 2000-2022. A total of 25 records reporting either transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) studies were found. The investigated clinical populations comprised different pathological conditions, including but not limited to SCA syndromes. The reviewed evidence supports that cerebellar neurostimulation is effective in improving social abilities in healthy individuals and reducing social and affective symptoms in different neurological and psychiatric populations associated with cerebellar damage or with impairments in functions that involve the cerebellum. These findings encourage to further explore the rehabilitative effects of cerebellar neurostimulation on socio-affective deficits experienced by patients with cerebellar abnormalities, as SCA patients. Nevertheless, conclusions remain tentative at this stage due to the heterogeneity characterizing stimulation protocols, study methodologies and patients' samples.

Cognitive, Social, and Emotional-Behavioral Outcomes in Children and Adolescents With Beckwith-Wiedemann Syndrome.

Although Beckwith-Wiedemann syndrome spectrum (BWSp) is not usually associated with intellectual disability, recent evidences calls for further investigation of cognitive development and academic skills in children with BWSp. Moreover, research has documented social difficulties and emotional-behavioral problems associated with BWSp. Nevertheless, a full characterization of socio-emotional development in BWSp is still lacking. In the current study, cognitive and socio-emotional development was assessed in 29 children with BWSp aged 5-18 years, using a test of nonverbal intelligence, a neuropsychological battery covering multiple domains, academic skills tests, and questionnaires evaluating autistic traits and emotional-behavioral problems. As expected, most participants showed adequate performance in cognitive tests. However, the findings also highlighted greater difficulties in language than visuospatial processing, strengths in social perception, as well as slowness in reading and mental calculation. The assessment of emotional-behavioral difficulties indicated a prevalent phenotype characterized by increased anxiety, low self-esteem, social withdrawal and a tendency to control externalizing reactions, but no associations with autistic traits, cognitive outcomes, and the clinical score proposed by the recent Consensus statement. Increased social perception and internalization problems likely result from coping strategies with social and care-related stress. Overall, the findings of this study inform clinical management and genetic counseling for children and adolescents with BWSp.

Contextual Priors Guide Perception and Motor Responses to Observed Actions.

In everyday-life scenarios, prior expectations provided by the context in which actions are embedded support action prediction. However, it is still unclear how newly learned action-context associations can drive our perception and motor responses. To fill this gap, we measured behavioral (Experiment 1) and motor responses (Experiment 2) during two tasks requiring the prediction of occluded actions or geometrical shapes. Each task consisted of an implicit probabilistic learning and a test phase. During learning, we exposed participants to videos showing specific associations between a contextual cue and a particular action or shape. During the test phase, videos were earlier occluded to reduce the amount of sensorial information and induce participants to use the implicitly learned action/shape-context associations for disambiguation. Results showed that reliable contextual cues made participants more accurate in identifying the unfolding action or shape. Importantly, motor responses were modulated by contextual probability during action, but not shape prediction. Particularly, in conditions of perceptual uncertainty the motor system coded for the most probable action based on contextual informativeness, regardless of action kinematics. These findings suggest that contextual priors can shape motor responses to action observation beyond mere kinematics mapping.

Spatial frequency tuning of motor responses reveals differential contribution of dorsal and ventral systems to action comprehension.

Understanding object-directed actions performed by others is central to everyday life. This ability is thought to rely on the interaction between the dorsal action observation network (AON) and a ventral object recognition pathway. On this view, the AON would encode action kinematics, and the ventral pathway, the most likely intention afforded by the objects. However, experimental evidence supporting this model is still scarce. Here, we aimed to disentangle the contribution of dorsal vs. ventral pathways to action comprehension by exploiting their differential tuning to low-spatial frequencies (LSFs) and high-spatial frequencies (HSFs). We filtered naturalistic action images to contain only LSF or HSF and measured behavioral performance and corticospinal excitability (CSE) using transcranial magnetic stimulation (TMS). Actions were embedded in congruent or incongruent scenarios as defined by the compatibility between grips and intentions afforded by the contextual objects. Behaviorally, participants were better at discriminating congruent actions in intact than LSF images. This effect was reversed for incongruent actions, with better performance for LSF than intact and HSF. These modulations were mirrored at the neurophysiological level, with greater CSE facilitation for congruent than incongruent actions for HSF and the opposite pattern for LSF images. Finally, only for LSF did we observe CSE modulations according to grip kinematics. While results point to differential dorsal (LSF) and ventral (HSF) contributions to action comprehension for grip and context encoding, respectively, the negative congruency effect for LSF images suggests that object processing may influence action perception not only through ventral-to-dorsal connections, but also through a dorsal-to-dorsal route involved in predictive processing.

Updating implicit contextual priors with explicit learning for the prediction of social and physical events.

For proper action understanding we can infer action intention from the kinematic features of movement (the event in terms of sensorial evidence) and/or from the contextual scenario in which the action occurs. In line with predictive coding theories, the implicit learning of statistical regularities between events and contextual cues strongly biases action prediction. Here, we assessed the relative sensitivity of contextual priors to an explicit learning aimed at reinforcing either context-based or event-based prediction. First, in an implicit learning phase we exposed participants to videos showing specific associations between a contextual cue and a particular event (action or shape) in order to create high or low contextual priors. Then, in an explicit learning phase we provided a feedback reinforcing the response suggested by the contextual prior or by the sensory evidence. We found that the former improved the ability to predict the unfolding of social or physical events embedded in high-probability contexts and worsened the prediction of those embedded in low-probability contexts. Conversely, the latter had weaker effects, ultimately failing to override the reliance on contextual priors. Further, we acknowledged an association between the extent of individual autistic traits and the ability to leverage explicit learning mechanisms encouraging perceptual information.

Self-body recognition and attitudes towards body image in younger and older women.

Despite the fact that ageing causes dramatic changes in bodily appearance, little is known about how self-body recognition changes across life span. Here, we investigated whether older, compared to younger women, differed in the ability of recognising their own than other women's body parts and whether this effect was associated to negative body image dispositions. Twenty-eight young (Mage: 25.93 years, SDage = 4.74) and 25 middle-aged (Mage: 54.36 years, SDage = 4.54) women completed an implicit task consisting of visual matching of self and others' body parts and an explicit self-other body discrimination task. Stimuli comprised of images of body parts of the participant and of other age- and BMI-matched models, which were presented in the original size or modified to look rounder or thinner. Measures of adiposity (i.e. BMI), body image concerns and appearance-related worries for specific body parts and for the whole body were also collected. Whilst both groups showed a self-body advantage in the implicit, but not in the explicit task, the advantage was notably bigger for the younger group. However, the implicit self-advantage was higher in those middle-aged women that displayed more body image concerns and worries for specific body parts. Furthermore, the two groups were comparably less able in recognising their body parts when presented thinner as compared to rounder or in their actual size. Overall, these findings open the possibility that, as women age, their implicit self-recognition abilities may decline in association with more negative body image dispositions.

Experience-dependent reshaping of body gender perception.

Protracted exposure to specific stimuli causes biased visual aftereffects at both low- and high-level dimensions of a stimulus. Recently, it has been proposed that alterations of these aftereffects could play a role in body misperceptions. However, since previous studies have mainly addressed manipulations of body size, the relative contribution of low-level retinotopic and/or high-level object-based mechanisms is yet to be understood. In three experiments, we investigated visual aftereffects for body-gender perception, testing for the tuning of visual aftereffects across different characters and orientation. We found that exposure to a distinctively female (or male) body makes androgynous bodies appear as more masculine (or feminine) and that these aftereffects were not specific for the individual characteristics of the adapting body (Exp.1). Furthermore, exposure to only upright bodies (Exp.2) biased the perception of upright, but not of inverted bodies, while exposure to both upright and inverted bodies (Exp.3) biased perception for both. Finally, participants' sensitivity to body aftereffects was lower in individuals with greater communication deficits and deeper internalization of a male gender role. Overall, our data reveals the orientation-, but not identity-tuning of body-gender aftereffects and points to the association between alterations of the malleability of body gender perception and social deficits.

Associations of observer's gender, Body Mass Index and internalization of societal beauty ideals to visual body processing.

We examined whether visual processing mechanisms of the body of conspecifics are different in women and men and whether these rely on westernised socio-cultural ideals and body image concerns. Twenty-four women and 24 men performed a visual discrimination task of upright or inverted images of female or male bodies and faces (Experiment 1) and objects (Experiment 2). In Experiment 1, both groups of women and men showed comparable abilities in the discrimination of upright and inverted bodies and faces. However, the gender of the human stimuli yielded different effects on participants' performance, so that female faces, and male bodies appeared to be processed less configurally than female bodies and male faces, respectively. Interestingly, the reduction of configural processing for male bodies was significantly predicted by participants' Body Mass Index (BMI) and their level of internalization of muscularity. Our findings suggest that configural visual processing of bodies and faces in women and men may be linked to a selective attention to detail needed for discriminating salient physical (perhaps sexual) cues of conspecifics. Importantly, BMI and muscularity internalization of beauty ideals may also play a crucial role in this mechanism.

Effectiveness of Computerized Cognitive Training Programs (CCTP) with Game-like Features in Children with or without Neuropsychological Disorders: a Meta-Analytic Investigation.

Computerized cognitive training programs (CCTP) are based on the assumption that cognitive abilities may be boosted by repetitively performing challenging tasks. The integration of game-like features in these programs, associated with the goal of amusing or rewarding participants, may contribute to generate cognitive benefits. Indeed, reinforcement contingencies have been reported to produce positive effects on performance and motivation, especially in children. This meta-analysis was aimed at providing a quantitative summary of the effectiveness of CCTP with game-like features in school-aged children with typical and atypical development. A total of 24 studies, with the cognitive and behavioral outcome data of 1547 participants, were selected for inclusion in the meta-analysis. Subgroup analyses were performed to identify the sources of the observed methodological heterogeneity. A robust variance estimation model, after removal of study outliers, yielded a small-to-moderate significant effect size. Final results pointed out smaller but more precise estimate effect sizes according to methodological aspects related to cognitive domain of outcomes, standardization of measures and type of control applied. Alongside supporting the use of CCTP for rehabilitating cognitive functions, the present results shed light on how different methodological choices are able to shape research findings in the field of children's cognitive rehabilitation.

Cerebellar Damage Affects Contextual Priors for Action Prediction in Patients with Childhood Brain Tumor.

Predictive coding accounts of action perception sustain that kinematics information is compared with contextual top-down predictions (i.e., priors) to understand actions in conditions of perceptual ambiguity. It has been previously shown that the cerebellum contributes to motor simulation of observed actions. Here, we tested the hypothesis that a specific contribution of the cerebellum to action perception is to provide contextual priors that guide the sampling of perceptual kinematic information. To this aim, we compared the performance of 42 patients with childhood brain tumor affecting infratentorial (ITT) or supratentorial (STT) areas with that of peers with typical development in an action prediction task. First, participants were exposed to videos depicting a child performing different reaching-to-grasp actions, which were associated with contextual cues in a probabilistic fashion. Then, they were presented with shortened versions of the same videos and asked to infer the action outcome; since kinematics was ambiguous, we expected their responses would be biased toward the previously learned contextual priors. We found that patients with brain tumor were impaired in predicting actions when compared to healthy controls. However, STT patients presented a reliable probabilistic effect, while ITT patients, who had cerebellar damage, did not rely on contextual priors in predicting actions. Furthermore, we found an association between the use of contextual priors and the ability to infer others' mental states as assessed by a standardized test. These results suggest that the cerebellum provides contextual priors to understand others' actions and this predictive function might underlie complex social cognition abilities.

Premature birth affects visual body representation and body schema in preterm children.

Research has demonstrated that from the first six months of life infants show early sensitivity to body visual features and rely on sensorimotor and proprioceptive inputs in forming representations of their own bodies. Premature birth interferes with typical exposition to visual, sensorimotor and proprioceptive stimulation, thus presumably affecting the development of body representations. Here, we tested this hypothesis by comparing the performance of preterm children with that of age-matched full-termchildren in two tasks assessing, respectively, visual body processing and body schema. We found that preterm children had spared configural processing but altered holistic processing of others' bodies and showed a general difficulty in expressing visuospatial judgements on body stimuli. Furthermore, body-centered visuospatial abilities were associated with specific impairments in operating object-based visuospatial transformations. The findings of this study indicate that preterm birth might interfere with the development of body representations at the levels of body visual perceptual processing and of body schema, with effects even on visuo-spatial abilities for non-bodily stimuli. Body-centered rehabilitative interventions should be proposed to preterm children in order to enhance visuo-spatial abilities and higher-level cognitive functions.

Effects of supratentorial and infratentorial tumor location on cognitive functioning of children with brain tumor.

PURPOSE: Effects of tumor location on cognitive performance of patients with brain tumor are controversial: some studies reported higher risks related to supratentorial locations, some to infratentorial locations, and still others did not find any differences. We aimed to address this issue by comparing school-aged children with supratentorial or infratentorial tumor with respect not only to cognitive outcomes but also to the associations between core cognitive domains and academic abilities. METHODS: 32 children with infratentorial tumor and 22 with supratentorial tumor participated in the study. To detect relationships among cognitive domains, we tested which neuropsychological variable(s) predicted academic skills, controlling for the effects of radiotherapy and time since diagnosis. RESULTS: Radiotherapy and time since diagnosis, but not tumor location, predicted cognitive outcomes. Radiotherapy negatively influenced attention and executive functioning, as well as reading speed and arithmetic operations accuracy. Unexpectedly, longer time since diagnosis was associated with improvement in attention and reading speed. Tumor location showed an effect on the relationships between core cognitive domains and academic skills: verbal and visual-spatial memory influenced reading and mathematical performance in supratentorial patients; in infratentorial patients, an only effect of visual-spatial memory on mathematical performance was detected. CONCLUSIONS: Tumor location seems not to influence cognitive performance, while radiotherapy constitutes a key risk factor for cognitive impairment. Attentional and reading abilities may improve over time, possibly due to the weakening of cancer care effects. Different patterns of cognitive associations seem to characterize supratentorial and infratentorial patients, probably associated with different neuroplastic reorganization processes after tumor occurrence.

Contextual priors do not modulate action prediction in children with autism.

Bayesian accounts of autism suggest that this disorder may be rooted in an impaired ability to estimate the probability of future events, possibly owing to reduced priors. Here, we tested this hypothesis within the action domain in children with and without autism using a behavioural paradigm comprising a familiarization and a testing phase. During familiarization, children observed videos depicting a child model performing actions in diverse contexts. Crucially, within this phase, we implicitly biased action-context associations in terms of their probability of co-occurrence. During testing, children observed the same videos but drastically shortened (i.e. reduced amount of kinematics information) and were asked to infer action unfolding. Since during the testing phase movement kinematics became ambiguous, we expected children's responses to be biased to contextual priors, thus compensating for perceptual uncertainty. While this probabilistic effect was present in controls, no such modulation was observed in autistic children, overall suggesting an impairment in using contextual priors when predicting other peoples' actions in uncertain environments.

Dissociated Representations of Deceptive Intentions and Kinematic Adaptations in the Observer's Motor System.

Previous studies showed that observing deceptive actions modulates the activity of the observer's motor system. However, it is unclear whether this modulation reflects the coding of deceptive intentions or the mapping of the kinematic adaptations required to attain deceptive actions. Here, we used single-pulse transcranial magnetic stimulation to measure cortico-spinal excitability (CSE) from hand and forearm muscles while participants predicted the weight of cubes lifted by actors who received truthful information on the object weight and provided 1) truthful (truthful actions) or 2) deceptive (deceptive actions) cues to the observers or 3) who received fooling information and were asked to provide truthful cues (deceived actions). This way, we independently manipulated actor's intentions and kinematic adaptations. We found that, as compared to truthful action observation, CSE increased during observation of deceptive actions, but decreased during observation of deceived actions. Importantly, while the CSE enhancement in response to deceptive intentions lacked muscle specificity, perceiving kinematic alterations in the deceived condition affected CSE only for the hand muscle involved in kinematic adaptations to unexpected object weight. This suggests that actor's intentions and movement kinematics may be coded by the observer's motor system at different hierarchical levels of action representation.

Does hunger sharpen senses? A psychophysics investigation on the effects of appetite in the timing of reinforcement-oriented actions.

Evidence exists about the influence of interoception on time-keeping functions. In the current study we further addressed this topic by testing the effect of fasting and snack on the ability to estimate the duration of reinforcement-oriented grasping actions. We found that, after fasting, the time estimation for the grasping of a primary reinforcement (i.e., a muffin) was positively influenced by moderate hunger. By contrast, high hunger after fasting interfered with the timing estimation for the grasping of a neutral object (i.e., a notepad). We also reported that, after snack, individuals with high residual levels of hunger showed higher variability of responses for the timing of primary-reinforcement-oriented actions; conversely, those with low level of hunger (after snack) showed higher response variability in the timing of secondary-reinforcement-oriented actions. Finally, timing variability in the fasting condition negatively correlated with the Body Mass Index of our participants. Overall, our results indicate that both the modification of the physiological state and individual traits related to appetite might affect the subjective experience of time. This is in line with the accumulating evidence documenting the influence of interoception in temporal processing and, more in general, with the New Look in Perception theoretical view, stating that the perception of external events might be influenced by motivational states.

Early Brain Damage Affects Body Schema and Person Perception Abilities in Children and Adolescents with Spastic Diplegia.

Early brain damage leading to cerebral palsy is associated to core motor impairments and also affects cognitive and social abilities. In particular, previous studies have documented specific alterations of perceptual body processing and motor cognition that are associated to unilateral motor deficits in hemiplegic patients. However, little is known about spastic diplegia (SpD), which is characterized by motorial deficits involving both sides of the body and is often associated to visuospatial, attentional, and social perception impairments. Here, we compared the performance of a sample of 30 children and adolescents with SpD (aged 7-18 years) and of a group of age-matched controls with typical development (TD) at two different tasks tapping on body representations. In the first task, we tested visual and motor imagery abilities as assessed, respectively, by the object-based mental rotation of letters and by the first-person transformations for whole-body stimuli. In the second task, we administered an inversion effect/composite illusion task to evaluate the use of configural/holistic processing of others' body. Additionally, we assessed social perception abilities in the SpD sample using the NEPSY-II battery. In line with previously reported visuospatial deficits, a general mental imagery impairment was found in SpD patients when they were engaged in both object-centered and first-person mental transformations. Nevertheless, a specific deficit in operating an own-body transformation emerged. As concerns body perception, while more basic configural processing (i.e., inversion effect) was spared, no evidence for holistic (i.e., composite illusion) body processing was found in the SpD group. NEPSY-II assessment revealed that SpD children were impaired in both the theory of mind and affect recognition subtests. Overall, these findings suggested that early brain lesions and biased embodied experience could affect higher-level motor cognition and perceptual body processing, thus pointing to a strict link between motor deficits, body schema alterations, and person processing difficulties.

Contextualizing action observation in the predictive brain: Causal contributions of prefrontal and middle temporal areas.

Context facilitates the recognition of forthcoming actions by pointing to which intention is likely to drive them. This intention is thought to be estimated in a ventral pathway linking MTG with frontal regions and to further impact on the implementation of sensory predictions within the action observation network (AON). Additionally, when conflicting intentions are estimated from context, the DLPFC may bias action selection. However, direct evidence for the contribution of these areas to context-embedded action representations in the AON is still lacking. Here, we used a perturb-and-measure TMS-approach to disrupt neural activity, separately in MTG and DLPFC and subsequently measure cortico-spinal excitability while observing actions embedded in congruent, incongruent or ambiguous contexts. Context congruency was manipulated in terms of compatibility between observed kinematics and the action goal suggested by the ensemble of objects depicted in the environment. In the control session (vertex), we found an early facilitation and later inhibition for kinematics embedded in congruent and incongruent contexts, respectively. MTG stimulation altered the differential modulation of M1 response to congruent vs. incongruent contexts, suggesting this area specifies prior representations about appropriate object graspability. Interestingly, all effects were abolished after DLPFC stimulation highlighting its critical role in broader contextual modulation of the AON activity.