Affiliations: North Dakota State University, Faigo, ND, USA | Indiana University South Bend, South Bend, IN,
USA
Note: [] Corresponding author: Stephanie L. Simon-Dack, Department of
Psychology, Center for Visual Neuroscience, North Dakota State University, PO
Box 6050, Fargo, ND 58108-6050, USA. Tel.: +1 701 231 8624; Fax: +1 701 231
8426; E-mail: stephanie.simon-dack@ndsu.edu
Abstract: Imaging, transcranial magnetic stimulation, and psychophysiological
recordings of the congenitally blind have confirmed functional activation of
the visual cortex but have not extensively explained the functional
significance of these activation patterns in detail. This review systematically
examines research on the role of the visual cortex in processing spatial and
non-visual information, highlighting research on individuals with early and
late onset blindness. Here, we concentrate on the methods utilized in studying
visual cortical activation in early blind participants, including positron
emissions tomography (PET), functional magnetic resonance imaging (fMRI),
transcranial magnetic stimulation (TMS), and electrophysiological data,
specifically event-related potentials (ERPs). This paper summarizes and
discusses findings of these studies. We hypothesize how mechanisms of cortical
plasticity are expressed in congenitally in comparison to adventitiously blind
and short-term visually deprived sighted participants and discuss potential
approaches for further investigation of these mechanisms in future
research.
