The figure on the left depicts the modulation in neural activation that specifically resulted from attending to the orthographic (left), phonological (center), or semantic (right) features of repeatedly presented pseudowords. These findings converge with others in revealing that a variety of cortical regions are differentially involved in the processing of phonological and semantic information and suggest that the putative visual word form area in the occipitotemporal/fusiform region is sensitive to the phonological properties of words and pseudowords.

Sandak, R., Mencl, W.E., Frost, S.J., Rueckl, J.G., Katz, L., Moore, D., Mason, S.A., Fulbright, R.K., and Constable, R,T., (2004). The Neurobiology of Adaptive Learning in Reading: A Contrast of Different Training Conditions. Cognitive, Affective, and Behavioral Neuroscience, 4, 66-88.

fMRI was used to investigate the separate influences of orthographic, phonological, and semantic processing on the ability to learn new words and the cortical circuitry recruited to subsequently read those words. In a behavioral session, subjects acquired familiarity for three sets of pseudowords, attending to orthographic, phonological, or (learned) semantic features. Transfer effects were measured in an event-related fMRI session as the subjects named trained pseudowords, untrained pseudowords, and real words. Behaviorally, phonological and semantic training resulted in better learning than did orthographic training. Neurobiologically, orthographic training did not modulate activation in the main reading regions. Phonological and semantic training yielded equivalent behavioral facilitation but distinct functional activation patterns, suggesting that the learning resulting from these two training conditions was driven by different underlying processes. The findings indicate that the putative ventral visual word form area is sensitive to the phonological structure of words, with phonologically analytic processing contributing to the specialization of this region.