Seeing and Hearing Speech, Sounds, and Signs: Functional Magnetic Resonance Imaging Studies on Fluent and Dyslexic Readers
نویسندگان
چکیده
............................................................................................... v Introduction............................................................................................. 1 Review of the literature ............................................................................... 3 Auditory speech perception .................................................................... 3 Subcortical auditory pathway ......................................................... 3 Hierarchical organization of the auditory cortex .................................. 4 Speech-specific auditory processing ................................................ 6 Visual speech perception ..................................................................... 7 Crossmodal processing in the auditory cortex ..................................... 7 Feedback or feedforward modulation? ................................................... 9 Audiovisual speech perception .................................................................... 10 Audiovisual integration and interactions ........................................... 10 Audiovisual interactions in speech perception ..................................... 11 Attention and speech perception .......................................................... 13 Behavioral and theoretical aspects ....................................................... 13 Attentional modulation of sound-evoked responses .............................. 13 Attentional modulation of visual and audiovisual speech perception........... 15 Motor system in speech perception ......................................................... 16 The motor theory of speech .......................................................... 16 Mirror neurons ......................................................................... 17 Evidence of MNS-like system in humans ......................................... 18 Dyslexia and speech perception ............................................................ 20 Language and sensory processing deficits ........................................ 20 Functional findings ................................................................... 21 BOLD fMRI .......................................................................................... 22 Principles of the MR signal ......................................................... 23 Basis of BOLD signal changes ..................................................................... 24 Temporal relationships between neuronal activity, CBF, and BOLD .......... 25 Measurement devices and sequences .............................................. 27 Data-analysis methods ................................................................ 28 Benefits and limitations ............................................................. 30
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