Poster C60, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Blind individuals do not develop a reading area in ventral occipitotemporal cortex
Judy Kim1, Shipra Kanjlia1, Lotfi Merabet2, Marina Bedny1; 1Johns Hopkins University, 2Harvard Medical School
Reading acquisition leads to specialization for visual words in ventral occipital-temporal cortex (vOTC) (Cohen & Dehaene, 2004). What causes reading-selectivity in this particular anatomical location? The neurobiology of Braille, a tactile reading system used by blind individuals, provides a window into this question. A recent study of blind Braille readers found responses to Braille in a similar location of vOTC as sighted individuals (Reich et al., 2011), leading to the suggestion that vOTC has modality-independent predispositions for reading (Hannagan et al., 2015). However, the visual cortex of blind individuals participates in high-level language processing (Bedny et al., 2011). Does vOTC become specialized for Braille or language in blindness? Blind participants (n=10) performed a memory probe task with Braille words, consonant strings, tactile shapes, auditory words, and backward sounds (Experiment 1). Sighted participants (n=15) completed an analogous task with visual words, consonant strings, false fonts, auditory words and sounds (Experiment 2). Both groups performed an auditory sentence comprehension task with syntactically complex and simple sentences (Experiment 3). We find that vOTC function is different across groups. In blind individuals, vOTC responds more to Braille words than to consonant strings. By contrast, the sighted vOTC responds more to consonant strings than to visual words. VOTC of blind but not sighted adults is sensitive to grammatical structure of sentences. We conclude that vOTC of blind individuals does not specialize for Braille, but rather, responds to language generally. The neurobiology of reading is shaped by visual experience and the modality of the reading system.
Topic Area: LANGUAGE: Lexicon