Cortical activity to vibrotactile stimulation: An fMRI study in blind and sighted individuals
TL;DR: Results suggest cross‐modal adaptation to tactile stimulation in visual cortex independent of language processes, which may underlie observed S1 expansions in the reading finger representation and learned attentiveness to touch may explain similar expansion of parietal tactile attention regions.
read more
Abstract: Blind individuals show visual cortex activity during Braille reading. We examined whether such cross-modal activations reflect processing somatosensory stimuli independent of language by identifying cortical activity during a one-back vibrotactile matching task. Three groups (sighted, early-onset, and late-onset [>12 years] blind) detected whether paired vibrations (25 and 100 Hz), delivered to the right index finger, differed in frequency. Three successive paired vibrations, followed by a no-stimulation interval, were presented in a long event-related design. A fixed effects average z-score analysis showed increased activity throughout the visuotopic visual cortex, where it was mostly restricted to foveal and parafoveal eccentricities. Early blind showed the most extensive distribution of activity. Late blind exhibited activity mostly in similar regions but with declining response magnitudes with age of blindness onset. Three sighted individuals had suprathreshold activity in V1 but negative responses elsewhere in visual cortex. Mixed effects ANOVA confirmed group distinctions in defined regions (V1, V3, V4v, V7, LOC, and MT). These results suggest cross-modal adaptation to tactile stimulation in visual cortex independent of language processes. All groups showed increased activity in left primary (S1) and bilateral second somatosensory areas, but without response magnitude differences between groups throughout sensorimotor cortex. Early blind showed the greatest spatial extent of S1 activity. Blind participants had more extensive bilateral activity in anterior intraparietal sulcus and supramarginal gyrus. Extensive usage of touch in Braille reading may underlie observed S1 expansions in the reading finger representation. In addition, learned attentiveness to touch may explain similar expansion of parietal tactile attention regions.
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Citations
Somatosensory processes subserving perception and action
TL;DR: It is suggested that, analogously to the organisation of the visual system, somatosensory processing for the guidance of action can be dissociated from the processing that leads to perception and memory.
Surface-based and probabilistic atlases of primate cerebral cortex.
TL;DR: Linking different brain atlases to one another and to online databases containing a growing body of neuroimaging data will enable powerful forms of data mining that accelerate discovery and improve research efficiency.
581
See me, hear me, touch me: multisensory integration in lateral occipital-temporal cortex.
TL;DR: Within superior temporal sulcus, a patchy organization of regions is activated in response to auditory, visual and multisensory stimuli, suggesting that it is an anatomical substrate for mult isensory integration.
426
Heteromodal connections supporting multisensory integration at low levels of cortical processing in the monkey
Céline Cappe,Pascal Barone +1 more
TL;DR: The results provide the anatomical pathway for multisensory integration at low levels of information processing in the primate and argue against a strict hierarchical model.
400
Preserved functional specialization for spatial processing in the middle occipital gyrus of the early blind
Laurent Renier,Laurent Renier,Irina Anurova,Irina Anurova,Anne De Volder,Synnöve Carlson,Synnöve Carlson,Synnöve Carlson,John W. VanMeter,Josef P. Rauschecker,Josef P. Rauschecker +10 more
TL;DR: Although the sensory modalities driving the neurons in the reorganized OC of blind individuals are altered, the functional specialization of extrastriate cortex is retained regardless of visual experience.
342
References
Computerized mappings of the cerebral cortex: A multiresolution flattening method and a surface-based coordinate system
Heather A. Drury,David C. Van Essen,Charles H. Anderson,Christopher W. Lee,Thomas A. Coogan,James W. Lewis +5 more
TL;DR: A surface-based coordinate system that has advantages over conventional stereotaxic coordinates and is relevant to studies of cortical organization in humans as well as non-human primates is introduced.
265
Enhanced Excitability of the Human Visual Cortex Induced by Short-term Light Deprivation
Babak Boroojerdi,Khalaf Bushara,Brian Corwell,Ilka Immisch,Fortunato Battaglia,Wolf Muellbacher,Leonardo G. Cohen +6 more
TL;DR: A substantial increase in visual cortex excitability was demonstrated after a short period of light deprivation, which may underlie behavioral gains reported in humans and animals associated with light deprivation.
263
Tactile motion activates the human middle temporal/V5 (MT/V5) complex.
Matthew C. Hagen,Ove Franzén,Francis McGlone,Francis McGlone,Gregory K Essick,Christopher Dancer,Christopher Dancer,José V. Pardo,José V. Pardo +8 more
TL;DR: In this subject, tactile motion produced a significant increase in rCBF that directly overlapped a region activated by visual motion at the posterior continuance of the inferior temporal sulcus, consistent with the known location of hMT/V5.
254
Tactile Attention Tasks Enhance Activation in Somatosensory Regions of Parietal Cortex: A Positron Emission Tomography Study
Harold Burton,Nicholas S. Abend,A.K. MacLeod,R.J. Sinclair,Abraham Z. Snyder,Marcus E. Raichle +5 more
TL;DR: Modulation of S1 and S2 supports concepts of early selection in tactile attention, and the posterior parietal region may be subdivided into modality-specific subregions, each of which processes information needed to attend to a specific modality.
220