Visual training and emotional state of people with retinitis pigmentosa.

The purpose of the study was to improve the visual functioning of people with restriction in contrast sensitivity (CS), such as retinitis pigmentosa (RP), by means of a visual training program. Twenty-six volunteers with RP participated, distributed in two groups: 15 who made up the experimental group (who received the training program) and 11 who participated as a control group (without training). Participants were evaluated before beginning training, on completion, and 3 mo following completion for CS with the Pelli-Robson Contrast Sensitivity (P&R) test, visual functioning with the Visual Function Questionnaire (VFQ), and in emotional state with the Beck Depression Inventory (BDI). The training program is based on software that generates luminous stimuli of varying duration and intensity and registers the stimuli perceived by the subject. The outcomes showed significant differences posttraining in the experimental group in depression (F1,14 = 5.42; p < 0.04), VFQ (Z = -2.27; p < 0.02), and P&R in the right eye (Z = -1.99; p < 0.046) and left eye (Z = -2.30; p < 0.02) but not in binocular (Z = -0.96; p < 0.34). The outcomes showed that the experimental group made significant progress in all variables and these effects remained after 3 mo, which suggests that the program could be a helpful addition to RP rehabilitation and help mitigate the damage.

A design framework to model retinas.

Neuro-engineering is providing biomedical engineers with technology to interface the nervous system, which is useful to create prosthetic devices to palliate sensorial or motor disabilities. Motivated by the success of cochlear implants for deaf patients, we are now facing the challenge of creating a prosthetic visual system for the blind. An artificial retina whose response to stimuli can be matched to biological ones is required. To make easier the task of modeling, tuning and testing these retinal models, we have created a software tool that allows flexible and parametric definition and testing of retina-like models. The program can be fed with a variety of video or image sources, and the results can be easily compared to biological recordings of retinal ganglionar activity in response to the same stimuli. This tool can be useful, not only for this prosthetic purpose, but for any other research involving bio-inspired image processing with a neuromorphic output.