Lateral response dynamics and hemispheric dominance for speech perception

The University of Sheffield, Sheffield, England, United Kingdom
Neuroreport (Impact Factor: 1.52). 09/2007; 18(12):1295-9. DOI: 10.1097/WNR.0b013e32827420e4
Source: PubMed


In this study, we investigated the mechanism for the left cerebral hemisphere's dominance for speech perception. We utilized the crossover of auditory pathways in the central nervous system to present speech stimuli more directly to the left hemisphere (via the right ear) and right hemisphere (via the left ear). Using functional MRI, we found that estimated duration of neural response in the left auditory cortex increased as more speech information was directly received from the right ear. Conversely, response duration in the right auditory cortex was not modulated when more speech information was directly received from the left ear. These data suggest that selective temporal responding distinguishes the dominant from nondominant hemisphere of the human brain during speech perception.

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    • "The left SMG, which we found to be hyper-responsive to external speech in hallucinators, is located at the temporoparietal junction and is a heteromodal region involved in processing and integrating multisensory inputs (Matsuhashi et al., 2004). Left-lateralisation of SMG hypersensitivity to speech is compatible with a stimulus content effect, given the left hemisphere's functional lateralisation for speech processing (Hunter et al., 2007). In schizophrenia, activation of the left SMG has been shown to occur during auditory hallucinations (Sommer et al., 2008). "
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    Proceedings of the National Academy of Sciences 02/2015; 112(10). DOI:10.1073/pnas.1414924112 · 9.67 Impact Factor
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