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This paper proposes a new navigation device to assist visually impaired people reach a defined destination safely in the indoor environment. This approach based on visual-auditory substitution provides the user a 2D spatial sound perception of the destination and of nearby and dangerous obstacles. Visual markers are placed at several relevant locations to create a mesh of the building where each marker is visually accessible from another marker. A graph representation of markers locations and their connection to each other defines by a way finding algorithm the shortest path reach to the wished position. The navigation task is achieved by moving from visual marker to visual marker until the desired destination is reached. These markers can be used independently of any other system or in addition to other solutions based on geolocalisation and/or a digital building model. Moreover, further information can be associated to the markers, and therefore verbalize to the user for instance a temporary hazards, a door presence or any other usual displayed information. The passive visual markers enables to deploy easily and quickly a scalable and low-cost solution to "signpost" the environment for users. Combined with our realtime implemented obstacle detection, their analysis enables the navigational abilities of visually impaired people to be improved.

Summary This article addresses the issue of animation as an aid for temporal processing difficulties in deaf people learning the Highway Code. A decision‐making task involving static or animated road situations was performed by 21 deaf and 24 hearing participants. They were confronted with four types of driving situations (overtaking, negotiating roundabouts, highways, and intersections) and had to decide whether or not to proceed. Participants were presented with two different formats (static vs. animated) and two levels of difficulty (simple vs. complex). Results showed that deaf participants had poorer performances in the static condition than hearing participants. Performance was better in the animated condition than in the static condition, especially in deaf participants. The benefits of animation were greater in complex situations for all participants. Decisions made on dynamic road situations were facilitated by the presence of spatiotemporal dimensions. These proved helpful to deaf candidates who have difficulties in this particular area.

The question of the possible impact of deafness on temporal processing remains unanswered. Different findings, based on behavioral measures, show contradictory results. The goal of the present study is to analyze the brain activity underlying time estimation by using functional near infrared spectroscopy (fNIRS) techniques, which allow examination of the frontal, central and occipital cortical areas. A total of 37 participants (19 deaf) were recruited. The experimental task involved processing a road scene to determine whether the driver had time to safely execute a driving task, such as overtaking. The road scenes were presented in animated format, or in sequences of 3 static images showing the beginning, mid-point, and end of a situation. The latter presentation required a clocking mechanism to estimate the time between the samples to evaluate vehicle speed. The results show greater frontal region activity in deaf people, which suggests that more cognitive effort is needed to process these scenes. The central region, which is involved in clocking according to several studies, is particularly activated by the static presentation in deaf people during the estimation of time lapses. Exploration of the occipital region yielded no conclusive results. Our results on the frontal and central regions encourage further study of the neural basis of time processing and its links with auditory capacity.

It is now possible to perform resections of slow-