Visual Processing & Eye Movement Journal Club
Past Event Date:
Meeting room:Room 204 - Main Conference Room
Kids are surprisingly old (~10.5 years) before they combine some sensory cues efficiently. Audrey will present evidence that this reflects the developmental trajectory of sensory-level fusion, rather than post-perceptual decision processes.
Presenter: Audrey Wong-Kee-You
Title: Late Development of Cue Integration Is Linked to Sensory Fusion in Cortex
Paper: Dekker et al., 2015, Current Biology
Adults optimize perceptual judgements by integrating different types of sensory information. This engages specialized neural circuits that fuse signals from the same or different modalities. Whereas young children can use sensory cues independently, adult-like precision gains from cue combination only emerge around ages 10 to 11 years. Why does it take so long to make best use of sensory information? Existing data cannot distinguish whether this reflects surprisingly late changes in sensory processing (sensory integration mechanisms in the brain are still developing) or depends on post- perceptual changes (integration in sensory cortex is adult-like, but higher-level decision processes do not access the information). We tested visual depth cue integration in the developing brain to distinguish these possibilities. We presented children aged 6–12 years with displays depicting depth from binocular disparity and relative motion and made measurements using psychophysics, retinotopic mapping, and pattern classification fMRI. Older children (>10.5 years) showed clear evidence for sensory fusion in V3B, a visual area thought to integrate depth cues in the adult brain. By contrast, in younger children (<10.5 years), there was no evidence for sensory fusion in any visual area. This significant age difference was paired with a shift in perceptual performance around ages 10 to 11 years and could not be ex- plained by motion artifacts, visual attention, or signal quality differences. Thus, whereas many basic visual processes mature early in childhood, the brain circuits that fuse cues take a very long time to develop.