Possible roles for fronto-striatal circuits in reading disorder.
Several studies have reported hyperactivation in frontal and striatal regions in individuals with reading disorder (RD) during reading-related tasks. Hyperactivation in these regions is typically interpreted as a form of neural compensation related to articulatory processing. Fronto-striatal hyperactivation in RD could however, also arise from fundamental impairment in reading related processes, such as phonological processing and implicit sequence learning relevant to early language acquisition. We review current evidence for the compensation hypothesis in RD and apply large-scale reverse inference to investigate anatomical overlap between hyperactivation regions and neural systems for articulation, phonological processing, implicit sequence learning. We found anatomical convergence between hyperactivation regions and regions supporting articulation, consistent with the proposed compensatory role of these regions, and low convergence with phonological and implicit sequence learning regions. Although the application of large-scale reverse inference to decode function in a clinical population should be interpreted cautiously, our findings suggest future lines of research that may clarify the functional significance of hyperactivation in RD.
Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, Box 0984, San Francisco, CA 94143, United States. Electronic address: Roeland.Hancock@ucsf.edu.
Roeland
R
Hancock
Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria.
Fabio
F
Richlan
Department of Psychiatry and Weill Institute for Neurosciences, University of California, San Francisco, Box 0984, San Francisco, CA 94143, United States; Haskins Laboratories, 300 George St #900, New Haven, CT 06511, United States; Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi Shinjuku, Tokyo, 160-8582 Japan.
Fumiko
F
Hoeft
D001921:Brain; D004410:Dyslexia; D006801:Humans; D007858:Learning; D011932:Reading
Articulation; Compensation; Dyslexia; Implicit learning