Luca Francesco Ticini

Chronic stroke recovery after combined BCI training and physiotherapy: a case report.

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

The Impact of Aesthetic Evaluation and Physical Ability on Dance Perception

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

Action observation in the infant brain: The role of body form and motion

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

When sounds become actions: Higher-order representation of newly learned action sounds in the human motor system

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

Imitating others' actions: transcranial magnetic stimulation of the parietal opercula reveals the processes underlying automatic imitation

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

Peripheral homonymous hemianopia: Correlation between lesion location and visual field defects by means of cytoarchitectonic probabilistic maps

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

IPL-M1 interaction shapes pre-reflective social differentiation in the human action system: new insights from TBS and TMS combined

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

Neuroestetica: le basi neurobiologiche della bellezza e del benessere

Recenti studi hanno dimostrato il ruolo importante della partecipazione ad attivita culturali nel benessere psicologico dell’individuo. In altre parole, andare a teatro, suonare uno strumento musicale e frequentare una galleria d’arte diminuirebbero i livelli d’ansia e di depressione [1]. Dedicare del tempo ad attivita culturali potrebbe percio dimostrarsi un approccio terapeutico preventivo al decadimento della salute psicofisica e contribuire perfino a ridurre la spesa dedicata alle cure farmacologiche e all’ospedalizzazione, che assorbono le gia scarse risorse stanziate per la salute mentale (la popolazione affetta da problemi mentali supera i 450 milioni di persone1). Invece, troppo spesso la cultura e confinata nella sfera irrilevante del divertimento, come testimoniano i frequenti tagli applicati alle risorse dedicate a questo settore. Per la sensibilizzazione degli apparati governativi verso tali tematiche e per la comprensione del reale contributo della partecipazione culturale al benessere dell’individuo, e senza dubbio necessario verificare con studi scientifici come una regolare partecipazione a eventi culturali possa influenzare l’attivita, la struttura e la biochimica delle strutture cerebrali responsabili della sensazione di piacere e ricompensa. Il ruolo delle neuroscienze in questo frangente e molto importante per capire, ad esempio, se la frequente esposizione a stimoli artistici attivi particolari strutture nervose o ne aumenti la connettivita, moduli il rilascio di neurotrasmettitori oppure induca un aumento del volume in precisi settori della corteccia cerebrale. Finora, con l’ausilio delle avanzate tecniche di visualizzazione dell’attivita cerebrale, come la risonanza magnetica funzionale (fMRI), i neuroscienziati hanno potuto approfondire in modo sistematico soltanto alcuni di questi aspetti, riuscendo a identificare le strutture neurali dedicate alla bellezza e alla percezione di benessere, lasciando tuttavia aperte possibilita di ricerca molto stimolanti.