Search results for "Mirror neuron system"
showing 7 items of 7 documents
Modulation of cortical motor outputs by the symbolic meaning of visual stimuli.
2010
Abstract The observation of an action modulates motor cortical outputs in specific ways, in part through mediation of the mirror neuron system. Sometimes we infer a meaning to an observed action based on integration of the actual percept with memories. Here, we conducted a series of experiments in healthy adults to investigate whether such inferred meanings can also modulate motor cortical outputs in specific ways. We show that brief observation of a neutral stimulus mimicking a hand does not significantly modulate motor cortical excitability (Study 1) although, after prolonged exposure, it can lead to a relatively nonspecific modulation (Study 2). However, when such a neutral stimulus is p…
Action simulation in the human brain: Twelve questions
2013
Although the idea of action simulation is nowadays popular in cognitive science, neuroscience and robotics, many aspects of the simulative processes remain unclear from empirical, computational, and neural perspectives. In the first part of the article, we provide a critical review and assessment of action simulation theories advanced so far in the wider literature of embodied and motor cognition. We focus our analysis on twelve key questions, and discuss them in the context of human and (occasionally) primate studies. In the second part of the article, we describe an integrative neuro-computational account of action simulation, which links the neural substrate (as revealed in neuroimaging …
Predicting domain-specific actions in expert table tennis players activates the semantic brain network.
2018
Motor expertise acquired during long-term training in sports enables top athletes to predict the outcomes of domain-specific actions better than nonexperts do. However, whether expert players encode actions, in addition to the concrete sensorimotor level, also at a more abstract, conceptual level, remains unclear. The present study manipulated the congruence between body kinematics and the subsequent ball trajectory in videos of an expert player performing table tennis serves. By using functional magnetic resonance imaging, the brain activity was evaluated in expert and nonexpert table tennis players during their predictions on the fate of the ball trajectory in congruent versus incongruent…
Modulation of premotor mirror neuron activity during observation of unpredictable grasping movements.
2004
Using transcranial magnetic stimulation, we explored the properties of premotor mirror neurons during the passive observation of a reaching-grasping movement in human subjects. Two different experiments were run using video-clips as visual stimuli. Video-clips showed a normally performed (control stimulus) or an anomalous reaching-grasping movement executed by delaying the time of the appearance of the maximal finger aperture (experiment 1), or substituting it with an unpredictable closure (experiment 2). Motor evoked potentials were recorded at different time-points during the observation of the video-clips. Profiles of cortical excitability were drawn and compared with the kinematic profi…
Disabilità visiva e neuroni specchio
2009
Il seguente lavoro ha come obiettivo quello indagare, il possibile coinvolgimento del sistema dei neuroni specchio nella disabilità visiva, cercando di analizzare, in particolare, come il soggetto non vedente possa comprendere e conoscere l’azione degli altri privato dal corpus di informazioni provenienti dal canale visivo. L’ipotesi da verificare è se nei soggetti con disabilità visiva e nei soggetti con sviluppo tipico venga messo in gioco e con quale modalità, lo stesso sistema di neuroni specchio unitario (visivo-uditivo) per il riconoscimento dell’azione. Inoltre, lo studio dovrebbe consentire di verificare se la disabilità visiva ad esordio precoce (congenita) è in grado di aumentare …
Motor simulation via coupled internal models using sequential Monte Carlo
2011
We describe a generative Bayesian model for action understanding in which inverse-forward internal model pairs are considered 'hypotheses' of plausible action goals that are explored in parallel via an approximate inference mechanism based on sequential Monte Carlo methods. The reenactment of internal model pairs can be considered a form of motor simulation, which supports both perceptual prediction and action understanding at the goal level. However, this procedure is generally considered to be computationally inefficient. We present a model that dynamically reallocates computational resources to more accurate internal models depending on both the available prior information and the predic…
Disabilità visiva e neuroni specchio: processi di apprendimento nello sviluppo atipico
2009
Lo studio,verificherà: 1) che la modalità di codifica tra i soggetti non vedenti (acquisiti) e non vedenti (congeniti) segue dei circuiti neuronali differenti, ma che comunque coinvolgono il sistema dei neuroni specchio; 2) che l’attività dei neuroni specchio non è vincolata al solo input sensoriale della visione di un semplice movimento, ma ad un vero e proprio “vocabolario di atti” che il soggetto riconosce come dotati di significato e appartenenti alla propria esperienza soprattutto nel caso di una disabilità visiva acquisita (più grande e ricco è questo vocabolario di atti, più il soggetto è in grado di apprendere); 3) che comprendere l’effettivo significato di una frase, di un suono ch…