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The evolution of the arcuate fasciculus revealed with comparative DTI. Nat Neurosci 11: 426-428

Department of Anthropology, Emory University, 207 Anthropology Building, 1557 Dickey Drive, Atlanta, Georgia 30322, USA.
Nature Neuroscience (Impact Factor: 14.98). 05/2008; 11(4):426-8. DOI: 10.1038/nn2072
Source: PubMed

ABSTRACT The arcuate fasciculus is a white-matter fiber tract that is involved in human language. Here we compared cortical connectivity in humans, chimpanzees and macaques (Macaca mulatta) and found a prominent temporal lobe projection of the human arcuate fasciculus that is much smaller or absent in nonhuman primates. This human specialization may be relevant to the evolution of language.

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Available from: Todd M Preuss, Aug 27, 2015
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    • "Additional evidence that non-human primates can learn linear sequences of sounds defined by simple transitional probabilities between concatenated elements [Arnold and Zuberb€ uhler, 2006; Fitch and Friederici, 2012; Wilson et al., 2013] suggest further parallels that may underpin bihemispheric linguistic capacities in the modern human. A critical difference between the primate and the human brain is the set of LH structures and white matter connections that link posterior temporal to inferior frontal areas BA 44/45 [Rilling et al., 2008; Rolheiser et al., 2011]. In current models of language processing, these pathways are commonly associated with grammatical computations— most specifically with the processing of complex hierarchical structures and dependencies generated by supra-regular grammars [Friederici, 2011] which non-human primates are not capable of mastering [Fitch and Hauser, 2004]. "
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