title: Late development of cue integration is linked to sensory fusion in cortex.
abstract: Adults optimize perceptual judgements by integrating different types of sensory information [1, 2]. This engages specialized neural circuits that fuse signals from the same [3-5] or different [6] modalities. Whereas young children can use sensory cues independently, adult-like precision gains from cue combination only emerge around ages 10 to 11 years [7-9]. Why does it take so long to make best use of sensory information? Existing data cannot distinguish whether this (1) reflects surprisingly late changes in sensory processing (sensory integration mechanisms in the brain are still developing) or (2) depends on post-perceptual changes (integration in sensory cortex is adult-like, but higher-level decision processes do not access the information) [10]. 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 [3-5]. 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 explained by motion artifacts, visual attention, or signal quality differences. Thus, whereas many basic visual processes mature early in childhood [11, 12], the brain circuits that fuse cues take a very long time to develop.
authors.affiliation: Institute of Ophthalmology, University College London, 11-43 Bath Street, EC1V 9EL London, UK. Electronic address: t.dekker@ucl.ac.uk.
authors.forename: Tessa M
authors.initials: TM
authors.lastname: Dekker
authors.affiliation: Center for Information and Neural Networks, National Institute of Information and Communications Technology, 1-4 Yamadaoka, Suita, Osaka 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ban
authors.affiliation: Institute of Ophthalmology, University College London, 11-43 Bath Street, EC1V 9EL London, UK.
authors.forename: Bauke
authors.initials: B
authors.lastname: van der Velde
authors.affiliation: Birkbeck, University of London, Malet Street, WC1E 7HX London, UK; Psychology and Language Sciences, University College London, 26 Bedford Way, WC1H 0AP London, UK.
authors.forename: Martin I
authors.initials: MI
authors.lastname: Sereno
authors.affiliation: Department of Psychology, University of Cambridge, Downing Street, CB2 3EB Cambridge, UK.
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Welchman
authors.affiliation: Institute of Ophthalmology, University College London, 11-43 Bath Street, EC1V 9EL London, UK; Department of Psychology, Durham University, South Road, DH1 3LE Durham, UK.
authors.forename: Marko
authors.initials: M
authors.lastname: Nardini
mesh_terms: D000328:Adult; D001288:Attention; D001921:Brain / Q000254:growth & development; D001931:Brain Mapping / Q000379:methods; D002540:Cerebral Cortex / Q000254:growth & development / Q000502:physiology; D002648:Child; D003463:Cues; D003867:Depth Perception / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000254:growth & development / Q000502:physiology*; D010465:Perception / Q000502:physiology*; D010775:Photic Stimulation; D011601:Psychophysics / Q000379:methods; D015357:Vision Disparity / Q000502:physiology; D014793:Visual Cortex / Q000254:growth & development / Q000502:physiology*