Silvio Ionta

Fields |

Research directions

Techno-Cognitive Strategies against Maladaptive Plasticity

Most of us can effortlessly control body movements based on somatosensory information. However, the interruption of the brain-body communication, e.g. after spinal cord injury (SCI) may radically affect the way the body is represented in the central nervous system and the actual state of body representation after SCI is largely unexplored. In this project we will quantify the effects of partial and total peripheral input loss (complete and incomplete SCI) on different aspects of body representation.

In addition, current evidence on the benefits of automated therapy over conventional sensorimotor rehabilitation is controversial. This inconsistency might be due to the lacking control of cognitive involvement in the standard (passive) assistive robotic intervention for motor rehabilitation. In order to overcome this limitation, the present project will combine different technological solutions (e.g. exoskeleton) and cognitive re-training (e.g. mental simulation of movements) to establish bidirectional benefits between currently segregated treatments.

Visuo-tactile integration and sense of embodiment

The rubber hand illusion is an experimental protocol wherein the feeling of body ownership is manipulated via spatio-temporal congruency between visual (seen, but not felt, touch) and tactile sensory input (felt, but not seen, touch). However, the specific relationship between multisensory perception and body ownership is still to be understood. In the present project, participants' brain activity will be recorded through functional magnetic resonance during the perception and not of the rubber hand illusion.

Aim:
To associate brain activity and/or connectivity during a rubber hand experiment and scores of perceived hand ownership.

Experimental Approach:
The applicant will analyze fMRI data in terms of brain activity and/or functional connectivity. The applicant will then also collaborate with the experimental setup in the MR environment and with the support during fMRI data acquisition. The applicant will analyze questionnaires of subject ownership and then associate the scores with neuroimaging features. The applicant will be also involved in recruiting participants and writing a study report. Elementary knowledge in MATLAB and/or R is recommended, but not a requirement.

VR technology and human visuo-motor integration

Over a century of animal research investigated the neurophysiological basis of the influence of sensory perception on movement execution. In humans, behavioral observations show that alterations or interruption of visual input can affect motor performance. However, whether and how sensory input affects the execution of movements remains an open question.

Aim: (1) Evaluating the putative role of signals from sensory regions of the brain on movement execution. (2) Possible extension to eventual differences between neurotypical and neuropathic populations.

Experimental Approach:
The student will be trained in using brain stimulation and virtual reality to record data from healthy volunteers, with possible extension to clinical populations. The obtained results will be considered for publication in a scientific journal.

Vision and mental representation of movements

In everyday life, we continuously simulate the sequences of movements in order to predict the possible outcome of our actions to reach our goals. Despite our sensory perception (especially vision) has clear influences on the execution of our movements, the relationship between perception and the simulation of movements remains largely unexplored.

Aim:
Pushing forward previous work, this project aims at investigating the role of vision on mental simulation of movements.

Experimental Approach:
The student will record response time and accuracy from a sample of healthy participants in different vision conditions, with eventual extension to clinical populations.

Consciousness and body representation

Body representation can be manipulated through the rubber-hand illusion experiment, in which a person does not see his/her own being touched but instead sees an artificial hand being touched at the same time. Eventually, the artificial hand might be perceived as being his/her own, but sometimes this feeling is only processed unconsciously. However, an objective method to measure unconscious aspects of the rubber hand illusion are still under investigation.

Aim:
This work will evaluate associations between implicit (unconscious) measures of changes in ownership and neural changes in the brain of healthy individuals.

Experimental Approach:
Participants' brain activity will be recorded through functional magnetic resonance imaging (fMRI). The master student will help with data recording and analysis. S/he will also collaborate with experimental setup, will be involved in recruiting participants, and will write a study report. It is recommended to the applicant to have previous knowledge in MATLAB and/or R, but not a requirement.

Visuo-Tactile Integration and Body Ownership in Humans

How to grab an object? How to understand that the hand grabbing the object is ours? The spatio-temporal relationship between vision and touch is essential for object manipulation, as well as to create the sense of body ownership ("this hand is my hand"). However, the basic mechanisms are still under investigation.

Aim:
This study will reveal the causal role of the integration of visual and tactile information as well as in the attribution of self body-ownership of body parts.

Experimental Approach:
The student will learn how to use specific experimental setups able to manipulate the sense of body ownership via visuo-tactile integration healthy human volunteers.

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