Objective evaluation of stress with the blind by the monitoring of autonomic nervous system activity.

Accessibility for the blind in an urban space must be studied under real conditions in their daily environment. A new approach for evaluating the impact of environmental conditions on blind pedestrians is the objective measure of stress by the monitoring of the autonomic nervous system (ANS) activity. Original techniques of data analysis and spatial representation are proposed for the detection of the ANS activity through the assessment of the electrodermal activity. Skin resistance was recorded with an EmoSense system on 10 blind subjects who followed a charted course independently. The course was 1065 meters long and consisted of various environmental conditions in an urban space. The spatial frequency of the non-specific skin resistance responses was used to provide a more relevant representation of geographic hotspots. Results of statistical analysis based on this new parameter are discussed to conclude on phenomena causing mental stress with the blind moving in an urban space.