Study of Visual Function Evaluation for People with Severe Motor and Intellectual Disabilities Utilizing Near-Infrared Spectroscopy

Abstract

The purpose of this study was (1) assess the effectiveness of near-infrared spectroscopy (NIRS) for evaluating visual function of people with severe motor and intellectual disabilities (SMID), and (2) investigate the inference of characteristics of visual stimuli to response from them and to dynamics of cerebral blood flow. Twenty-one SMID were presented Visual Task 1 which uses a photograph, and classified into four groups based on subjects’ eye movement. Additionally, oxy-Hb which was most increased was measured. Results, the averages of oxy-Hb for “gaze” and “habituation” group were 0.45 and 0.83 mM*mm, “non-gaze” was almost 0 mM*mm, and “non-judgment” were resembled “gaze”. In Visual Task 2 which uses a moving image, most subjects were classified in “gaze”, and an oxy-Hb had increased. This study indicated that NIRS is an effective instrument for visual function evaluation, and that difference in the characteristics of stimuli could affect the responses and oxy-Hb of SMID.