Multisensory integration development for rehabilitation

In 2014 the number of blind children below the age of 15 years was estimated to be 19 million. Psychophysical evidence suggests that some tactile and audio skills in congenital blind individuals result enhanced, such as the ability to localize a sound source in the horizontal plane or discriminate between different sounds. Studies of animals confirm this view by suggesting that sound processing by neurons in auditory cortical areas can be enhanced following visual deprivation. On the other hand, recent psychophysical works have pointed out that some forms of auditory perception in visually impaired individuals result compromised, raising some doubts about the degree and the limits of cross-modal plasticity in the case of sensory loss. Blind individuals are impaired in complex skills such as sound localization in the mid-sagittal plane and tasks requiring a metric representation of the auditory space. The creation of new technological devices to be used early in life is a must. However, despite the huge improvement of technological devices specifically designed for visually impaired users, we find that many of these solutions are not widely accepted by adults, it is not suitable for young children and it is not meant for rehabilitation purposes. They result too complex because they imply the need of learning a new language following long training programs and integrating multiple sensory signals. In the talk I will present our studies on blind and low vision children and adults and some new technological solutions for rehabilitation we have developed for children and adults with visual impairment. An example is the use of the ABBI device (Audio Bracelet for Blind Interaction; www.abbiproject.eu). It is a new rehabilitation device that we have recently proposed that can be used by children with visual impairments from few year of age. It is based on the idea that an audio feedback related to body movement can be used to improve spatial and social cognition as well as mobility skills. We tested this device in 40 children from 3 to 17 years of age by performing a longitudinal three months rehabilitation training. During this period half subjects (experimental group) performed the training with ABBI for a total of 65 hours while the other group (control group) performed the typical rehabilitation without the audio-motor training with ABBI. Results suggest that the use of the audio-motor training with ABBI helps rehabilitating the sense of space and motor skills and that the improvement is maintained after one year of rehabilitation training. These findings show that an audio-motor training can be helpful to compensate for the lack of visual experience with long lasting effects.