The developing brain responds to the environment by using statistical correlations in input to guide functional and structural changesthat is, the brain displays neuroplasticity. Experience shapes brain development throughout life, but neuroplasticity is variable from one brain system to another. How does the early loss of a sensory modality affect this complex process? We examined cross-modal neuroplasticity in anatomically defined subregions of Heschl's gyrus, the site of human primary auditory cortex, in congenitally deaf humans by measuring the fMRI signal change in response to spatially coregistered visual, somatosensory, and bimodal stimuli. In the deaf Heschl's gyrus, signal change was greater for somatosensory and bimodal stimuli than that of hearing participants. Visual responses in Heschl's gyrus, larger in deaf than hearing, were smaller than those elicited by somatosensory stimulation. In contrast to Heschl's gyrus, in the superior-temporal cortex visual signal was comparable to somatosensory signal. In addition, deaf adults perceived bimodal stimuli differently; in contrast to hearing adults, they were susceptible to a double-flash visual illusion induced by two touches to the face. Somatosensory and bimodal signal change in rostrolateral Heschl's gyrus predicted the strength of the visual illusion in the deaf adults in line with the interpretation that the illusion is a functional consequence of the altered cross-modal organization observed in deaf auditory cortex. Our results demonstrate that congenital and profound deafness alters how vision and somatosensation are processed in primary auditory cortex.

Brain reorganization associated with altered sensory experience clarifies the critical role of neuroplasticity in development. An example is enhanced peripheral visual processing associated with congenital deafness, but the neural systems supporting this have not been fully characterized. A gap in our understanding of deafness-enhanced peripheral vision is the contribution of primary auditory cortex. Previous studies of auditory cortex that use anatomical normalization across participants were limited by inter-subject variability of Heschl's gyrus. In addition to reorganized auditory cortex (cross-modal plasticity), a second gap in our understanding is the contribution of altered modality-specific cortices (visual intramodal plasticity in this case), as well as supramodal and multisensory cortices, especially when target detection is required across contrasts. Here we address these gaps by comparing fMRI signal change for peripheral vs. perifoveal visual stimulation (11–15° vs. 2–7°) in congenitally deaf and hearing participants in a blocked experimental design with two analytical approaches: a Heschl's gyrus region of interest analysis and a whole brain analysis. Our results using individually-defined primary auditory cortex (Heschl's gyrus) indicate that fMRI signal change for more peripheral stimuli was greater than perifoveal in deaf but not in hearing participants. Whole-brain analyses revealed differences between deaf and hearing participants for peripheral vs. perifoveal visual processing in extrastriate visual cortex including primary auditory cortex, MT+/V5, superior-temporal auditory, and multisensory and/or supramodal regions, such as posterior parietal cortex (PPC), frontal eye fields, anterior cingulate, and supplementary eye fields. Overall, these data demonstrate the contribution of neuroplasticity in multiple systems including primary auditory cortex, supramodal, and multisensory regions, to altered visual processing in congenitally deaf adults.

The present study traced the emergence of the neural circuits for reading in five-year-old children of diverse pre-literacy ability. In the fall and winter of kindergarten, children performed a oneback task with letter versus false font stimuli during fMRI scanning. At the start of kindergarten, children with on-track pre-literacy skills (OT) recruited bilateral temporo-parietal regions for the letter > false font comparison. In contrast, children at-risk for reading difficulty (AR) showed no differential activation in this region. Following 3 months of kindergarten and, for AR children, supplemental reading instruction, OT children showed left-lateralized activation in the temporoparietal region, whereas AR children showed bilateral activation and recruitment of frontal regions including the anterior cingulate cortex. These data suggest that typical reading development is associated with initial recruitment and subsequent disengagement of right hemisphere homologous regions while atypical reading development may be associated with compensatory recruitment of frontal regions.Over the past 20 years, a number of neuroimaging studies have examined the nature, development, dysfunction, and remediation of cortical circuits for reading. Studies of proficient, adult readers have identified three left-hemisphere regions that comprise a putative reading network. These include dorsal and ventral posterior regions and one anterior region (Pugh et al., 2000(Pugh et al., , 2001Schlaggar and McCandliss, 2007). The posterior dorsal region, located at and around the temporo-parietal junction, including the posterior part of the superior temporal gyrus, supramarginal gyrus, and angular gyrus, has been hypothesized to be recruited for phonological processing (Church et al., 2008; Temple, © 2010 Elsevier Inc. All rights reserved.Correspondence should be addressed to Yoshiko Yamada (yyamada@uoregon.edu). Courtney Stevens is now at the Department of Psychology, Willamette University. David Chard is now at the School of Education and Human Development, Southern Methodist University.Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptNeuroimage. Author manuscript; available in PMC 2012 August 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript2002) and the conversion of orthographical (visual) information to phonological (auditory) form (Pugh et al., 2000(Pugh et al., , 2001Shaywitz et al., 1998), which involves integration of multimodal information (Booth et al., 2002;van Atteveldt et al., 2004). The posterior ventral region, ...

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Electroencephalographic (EEG) oscillations in multiple frequency bands can be observed during functional activity of the cerebral cortex. An important question is whether activity of focal areas of cortex, such as during finger movements, is tracked by focal oscillatory EEG changes. Although a number of studies have compared EEG changes to functional MRI hemodynamic responses, we can find no previous research that relates the fMRI hemodynamic activity to localization of the multiple EEG frequency changes observed in motor tasks. In the present study, five participants performed similar thumb and finger movement tasks in parallel EEG and functional MRI studies. We examined changes in five frequency bands (from 5–120 Hz) and localized them using 256 dense-array EEG (dEEG) recordings and high-resolution individual head models. These localizations were compared with fMRI localizations in the same participants. Results showed that beta-band (14–30 Hz) desynchronizations (power decreases) were the most robust effects, appearing in all individuals, consistently localized to the hand region of the primary motor cortex, and consistently aligned with fMRI localizations.