Mirror neurons and their relevance in neuro-rehabilitation

Can it contribute, through stimulation of mirror neurons, to functional recovery in patients with hemiparesis as a consequence of a stroke?

Mirror neurons and their usefulness in neurological rehabilitation

About a month ago it was published in Psychology and Mind an article related to mirror neurons in which they spoke, mainly, of their discovery and their importance in culture and social phenomena. This article aims to show, in broad strokes, the importance of these mirror neurons in the process of functional rehabilitation of the upper extremities in patients affected by Ictus.

What processes are mirror neurons involved in?

In 1996, Giacomo Rizzolati serendipitously discovered that these mirror neurons were activated by performing an action and seeing another person performing the same actionn, therefore, it can be concluded that they are essential for the learning and the imitation, while playing an important role in the social skills, such as the empathy, since thanks to them we can intuit what the other person thinks, is going to do or feels (Rizzolatti and Craighero, 2004).

By stimulating it, can you contribute to the rehabilitation of patients affected by stroke?

As mentioned, they are neurons that are involved in mechanisms that combine performance-observation. Therefore, based on these findings, it has been proven that their stimulation influences the rehabilitation process, thus, they have been carried out various functional neuro-rehabilitation programs, for example, in cases in which the patient presents motor deficits in the upper extremities as a result of a Stroke or Stroke.

An example of this is given to us through Rehabilitation Gamming System (RGS) ( http://rgs-project.eu), an innovative project of Virtual reality (RV) carried out by the research team of the SPECS laboratory, Pompeu Fabra University (UPF), Hospital del Mar, Hospital Valle Hebrón and three other entities in collaboration with the Fundació TicSalut.

This project is based on the principle of brain plasticity and how a functional reorganization can be achieved in the areas affected by stroke through the stimulation of the secondary motor areas (Cameirao, Bermúdez, Duarte & Verschure, 2011). Such areas make up the mirror neuron system (MNS), involved in motor planning and execution processes by observing said action.

RGS is an application that, through the use of VR through dynamic games, promotes the functional recovery of the patient. Thus, it allows the patient to advance in the process of upper extremity rehabilitation by stimulating the visual-motor pathway provided by the MNS. The material resources necessary to carry out this therapy through RGS are, mainly, a computer with Kinect sensor and RGS Software, as an addition, different interface devices can be added (gloves, exoskeletons, etc.). Through the image provided by the screen you can see a representation of virtual arms, shown in first-rate perspective. person, who simulate the movement of the real arms in real time and in a simulated environment, in this way, the patient activates the neural circuits injured motors, which are habitually inactive due to the lack of movement of the paretic arm, thus inducing neuroplasticity in the area affected. As for the various games that the program includes, they are mainly based on capturing objects, hitting them, dodging them, etc.

In addition, each game is adapted in terms of complexity and speed of the stimuli to the performance in each of the arms and characteristics of the patient. What is really interesting about this adaptation system is that it is dynamically modulated through two different strategies. On the one hand, it adjusts the difficulty of the exercise, and on the other, it amplifies the movement of the affected arm of the patient in VR, showing faster, wider and more precise reaching movements. In this way, the patient is motivated to use his affected arm more frequently.

Another interesting aspect of the RGS system is that allows you to capture descriptive parameters of the user's progress, to be automatically analyzed and presented, thus allowing clinical staff to monitor the patient's recovery process.

RGS has already been evaluated in several clinical studies that have demonstrated its efficacy in rehabilitation processes. These studies were conducted to verify the efficacy of therapy using RGS combined with Occupational Therapy (OT) in comparison with a control group that only received OT. The results showed that the group of patients with whom RGS was performed combined with OT obtained better results than the control group (Cameirao et al., 2011).

Finally, it can be concluded that RGS is a VR therapy based on neuronal plasticity by stimulating the MNS in which, in a playful and entertaining way, it can contribute to the improvement of the recovery of the mobility of the upper extremities in patients affected by stroke.

Bibliographic references:

• Cameirao, M.S, Bermúdez, S., Duarte, O., and Verschure, P. (2011). Virtual reality based rehabilitation speeds up functional recovery of the upper extremities after stroke: a randomized controlled pilot study in the acute phase of stroke using the rehabilitation gaming system. Restorative neurology and neuroscience, 29(5), 287-298.
• Rizzolatti, G., and Craighero, L. (2004). The mirror-neuron system. Annual Review of Neuroscience, 27, 169-192.
• The Rehabilitation Gaming System website (www.eodyne.com).