  The visual substitution paradigm aims to facilitate the life of blind people.
Generally one uses electro-stimulating devices where electrodes are arranged
into arrays to stimulate the skin or the tongue mucosa to send signals of
visual type to the subjects. When an electro-stimulation signal is applied
continuously (e.g. when static visual scenes are displayed for a long period of
time), the receptors of the affected region can get saturated and the patient
may lose the displayed information. We propose here some mechanisms that
ameliorate the quality of perception of the electro-stimulation information.
The electrical signal is encoded as 2D scenes projected onto the tongue via a
Tongue Display Unit, i.e. an electro-tactile stimulator formed by a 12x12
matrix of electrodes. We propose to apply stochastic saccades on this signal.
Our assumption is that this eye-inspired mechanism should make the visual
substitution more efficient (by improving the perception) because of the
reduction of the tactile receptors saturation. The influence of saccades was
evaluated by a series of experiments. Results revealed a benefit on the
persistence of perception due to saccades. This work helps to prevent the
saturation of receptors on the tongue. Therefore increasing the quality of
vision by the way of the electro-stimulation. It allows new enhancement
features to retinal prosthesis devices which suffer from the same phenomenon.
