Crossmodal enhancement in the LOC for visuohaptic object recognition over development

Abstract

Research has provided strong evidence of multisensory convergence of visual and haptic information within the visual cortex. These studies implement crossmodal matching paradigms to examine how systems use information from different sensory modalities for object recognition. Developmentally, behavioral evidence of visuohaptic crossmodal processing has suggested that communication within sensory systems develops earlier than across systems; nonetheless, it is unknown how the neural mechanisms driving these behavioral effects develop. To address this gap in knowledge, BOLD functional Magnetic Resonance Imaging (fMRI) was measured during delayed match-to-sample tasks that examined intramodal (visual-to-visual, haptic-to-haptic) and crossmodal (visual-to-haptic, haptic-to-visual) novel object recognition in children aged 7 to 8.5 years and adults. Tasks were further divided into sample encoding and test matching phases to dissociate the relative contributions of each. Results of crossmodal and intramodal object recognition revealed the network of known visuohaptic multisensory substrates, including the lateral occipital complex (LOC) and the intraparietal sulcus (IPS). Critically, both adults and children showed crossmodal enhancement within the LOC, suggesting a sensitivity to changes in sensory modality during recognition. These groups showed similar regions of activation, although children generally exhibited more widespread activity during sample encoding and weaker BOLD signal change during test matching than adults. Results further provided evidence of a bilateral region in the occipitotemporal cortex that was haptic-preferring in both age groups. This region abutted the bimodal LOtv, and was consistent with a medial to lateral organization that transitioned from a visual to haptic bias within the LOC. These findings converge with existing evidence of visuohaptic processing in the LOC in adults, and extend our knowledge of crossmodal processing in adults and children.

Visual Cortex Alterations in Early and Late Blind Subjects During Tactile Perception

“…Intact FC of motor, somatosensory area with occipital cortex in adolescent group of blinds in comparison to children group suggest that V3d-V3A and V5 areas subserve visuospatial and kinaesthetic processing in blind groups and SCs (Amedi et al., 2010; Jao et al., 2015; Sathian, 2016). Positive correlation between duration of training and hemodynamic signal variability suggests that blindness leads to specific cross-modal reorganization in right dorsal stream in concurrence with reports of early structural and functional modification of visual cortex (Lazzouni & Lepore, 2014).…”

“…The occipital fusiform gyrus and thalamus recruitment in LBs may be attributed to visual imagery processes associated with earlier visual experience and in SCs for object perception (Bauer et al., 2017; Renier et al., 2010). Furthermore, LB and SC groups may have used their (previous) visual experience to solve the task, suggestive of residual visual imagery capabilities affecting cross-modal plasticity (Collignon et al., 2013; Jao et al., 2015).…”

“…Touch perception sensory system is better in blind people when compared with sighted (blindfolded) people (Sathian, 2016;Sathian & Stilla, 2010). Neuroimaging and functional magnetic resonance imaging (fMRI) studies using blood oxygen level dependent (BOLD) have reported stimulation of visual cortex while processing tactile stimuli (such as microspatial task and tactile discrimination) in EB and LB in comparison to sighted controls (SCs; Burton et al, 2004;Collignon et al, 2013;Sabbah et al, 2017;Sathian & Stilla, 2010;Stilla et al, 2008) and during tactile object and shape identification tasks in EB and LB (Jao et al, 2015;Hinkley et al, 2009). Deprivation in a sensory modality leads to alterations in other sensory modalities, which may or may not cause changes in brain structure, function (neural interactions), and cognition processes (Lazzouni & Lepore, 2014).…”

Haptic and visuo-haptic impairments for object recognition in children with autism spectrum disorder: focus on the sensory and multisensory processing dysfunctions

“…Also, the choice is in line with neural data showing that the cortical networks involved in the recognition of familiar objects are the same for both vision and haptics modalities, independently of the fact that stimuli consist of real objects or photographs (Martinovic et al 2012 ). Finally, other published studies used similar procedures with realistic photographs on the grey scale to study visual-haptic recognition (Jao et al 2015 ; Joanne Jao et al 2014 ). As a matter of fact, our findings reveal that using photographs as visual stimuli did not disadvantage the ASD group compared to the TD group.…”