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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    • "Beside the right pSTG, the temporal region in the posterior fundus of the right STS (fpSTS) showed the strongest connection strength to frontal target regions, both along the right dorsal and ventral pathway. The fpSTS was the only region to target the right IFG, taking the right ventral pathway, which has been not well described in humans yet, but seems to have precursors in nonhuman primates (Ghazanfar, 2008; Rilling et al., 2008). Previously, we found that the fpSTS is active independent of the attentional focus, but exhibiting sensitivity to the features of acoustic features of affective prosody, such as pitch and intensity variations . "
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    • "Inconsistencies in detecting AF's frontal lobe endpoints may be due to different tracing algorithms. In our study and in Rilling et al. (2008) the newly developed probabilistic tractography algorithm was used, designed to track through crossing fibres by also considering the secondary diffusion direction (Behrens, Berg et al. 2007). On the contrary, Bernal and Ardila (2009) used the earlier-developed deterministic tractography (Mori, Crain et al. 1999). "
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