EVENT: Psychology colloquium: Prof David Burr: Cross-sensory integration and Calibration during development

Department of Neuroscience, University of Florence.

Title: Cross-sensory integration and calibration during development

Much evidence suggests that humans integrate information between senses in a statistically optimal manner, maximizing the precision of performance. We have recently shown that reliability-based integration of vision and touch develops only after about 8 years of age. In younger children one sense dominates the other: for size discrimination touch dominates vision but for orientation discrimination visual dominates. We suggest that the dominance of one or other sense reflects cross-modal calibration of developing systems: one sense calibrates the other, rather than fusing with it to improve precision. But unlike sensory fusion, it is the more robust and accurate sense that dominates the calibration, even if it is the less precise. Several lines of evidence support this idea: congenitally blind children show a selective deficit in haptic orientation-discrimination, and dyskinetic children (with highly impaired movement control) show a selective deficit in visual size judgments. Both these impairments could result from a lack of cross-sensory calibration in early development.