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The processes in the brain which enable humans to navigate independently through complex environments have been related to functionally identified neural structures involved in long-term memory representation. This study investigates the role of short-term memory representation, activated through brief exposure to the spatial layout of an unfamiliar complex environment. The effects of short-term memory processes on navigation performances of men and women were investigated. After two minutes of either 2D map or direct viewing (learning phase), individuals navigated from memory in Google Street View (test phase). Subjective ratings of psychological stress were recorded after testing. Satisfactory, and significantly better navigation performances compared with 2D map exposure, were found for both men and women after direct viewing. A significant effect of the sex factor was observed after 2D map exposure, where women produced the weakest performances, and the highest psychological stress ratings.We conclude that short-term memory representations of acomplex and novel spatial layout enable successful navigation, depending on the type of visual information made available through prior exposure. Direct visual experience is encoded more effectively by the brain than abstract map experience, especially by women, under the conditions investigated here.

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International audience; This study was designed to determine whether Coxsackie adenovirus receptor (CAR) and alpha nu beta3/alpha nu beta5 integrin co-receptors are involved in adenovirus gene transfer in the rat cochlea. We find that CAR and integrin co-receptors are expressed in every cell subtype transduced by the adenoviral vector Ad5 DeltaE1-E3/cytomegalovirus/green fluorescent protein (GFP) on cochlear slices in vitro. The spiral ganglion neurons, which do not express CAR, were not transduced by the virus. Blocking these receptors by monoclonal antibodies decreased transgene expression, whereas disrupting tight junctions with ethylenediaminetetraacetic acid led to an increased transgene expression. However, sensory hair cells and strial cells also expressing CAR and alpha nu integrins were not transduced by the vector. GFP expression was also studied in vivo. Perilymphatic perfusion of adenovirus in vivo did not affect hearing and only cells lining the perilymphatic spaces were transduced. Endolymphatic perfusion resulted in low-frequency hearing loss and although some cells of the organ of Corti were efficiently transduced, the sensory and the strial cells were not. Transduced sensory and strial cells were occasionally observed in cochleas after single shot of adenovirus. Pretreatment with anti-CAR and anti-alpha nu antibodies decreases GFP expression in vivo, suggesting that the CAR/alpha nu integrin pathway is involved in adenovirus transduction in the cochlea.