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International audience; When we look at our spatial environment we have the feeling that the whole visual field is coloured, yet the density of cone photoreceptors decreases considerably as eccentricity increases. We investigated colour perception (coloured/noncoloured), colour naming and whether colour helps object recognition at eccentricities varying from 0 degrees to 80 degrees in healthy observers and patients with low vision. We found that colours can be perceived and even identified above chance at very large eccentricities (60 degrees). When asked to categorize coloured and grey level objects as edible/nonedible, both healthy observers and patients with low vision showed better performance for coloured edible objects at 50 degrees suggesting that colour is used for object recognition in conditions of degraded form perception.

The ability to properly distinguish facial emotions has a protracted development, not maturing until well into adolescence. Emotional faces activate emotion-specific neural networks in adults; whether these networks are operational in children is not known. Using an implicit face-processing task in 10-year-old children, we determined that the emotions of fear, disgust and sadness recruited distinct neural systems. These systems included a number of regions typically associated with processing emotions in adults, namely the amygdala and parahippocampal gyrus, insula and cingulate gyrus, as well as the fusiform and superior temporal gyri. Thus, in spite of immature behavioral responses to emotional faces in explicit tasks, neural networks for emotion-specific processing are present in young children.

International audience; The attentional blink has been attributed to capacity limitations at a central level of processing. We tested whether failure to identify the target would eliminate the blink. Two agnostic patients were presented with streams of letters, which they were able to identify, and streams of pictures, which they were unable to identify. The dual-task involved identification of a target and detection of a probe. With letters the duration of the blink was equivalent to that of the control subjects. A prolonged blink was observed in both patients for pictures irrespective of whether the target was identified. This result indicates that failure to identify the target does nevertheless mobilize attentional resources sufficiently to prevent detection of a second target stimulus.