Audio-visual stimulation improves oculo-motor patterns in patients with hemianopia

To study the effects of multisensory training on saccadic movement. To compare improvements in visual performance between patients undergoing unimodal stimulation (control group) and bimodal stimulation (experimental group). To evaluate the long-term effects of results obtained through audio-visual stimulation. To compare the performance of hemianopic patients and healthy patients (not undergoing treatment).

Protocol

While maintaining the fixation point at the center, the patient must direct their gaze toward the stimuli. Eye movement is measured using an infrared tracker. The task is differentiated between the control group (required to respond to unimodal stimuli) and the experimental group (required to respond to bimodal audio-visual stimuli).

Results

At the end of treatment with audio-visual stimuli, all patients reported an improvement in visual exploration characterized by fewer fixations, faster saccadic movement, and a reduction in the visual scanning path, which overall resulted in a reduction in exploration time. Significant improvements were also observed in the reading speed test for both right and left hemianopia. The improvements remained stable even after 1 year of follow-up.

The study demonstrated that unimodal visual training alone does not lead to significant improvements in hemianopic patients, unlike bimodal training with audio-visual stimuli.