Magnetoencephalographic studies of neural systems associated with higher order processes in humans.
The Open University.
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This thesis has been concerned with the neuromagnetic fields associated with the processing of faces and sentences in humans. In four, largely independent sub-projects, results were obtained using novel methods of analysis to extract neurophysiologically relevant information from magnetoencephalographic MEG readings. Using the MEG facility of the Helsinki University of Technology, Finland, the research has led to four main suggestions: a) there are early latency face-specific neural systems in humans that are predominantly in right inferior occipito-temporal cortex, b) MEG recordings are useful in the study of autism, in that autistic subjects exhibit different responses to normal subjects following face presentation, c) phase-locked y-band activity has a specific role in semantic processing of sentences in normal subjects, and d) the late components of responses to face images are modified by endogenous priming, which is detectable before stimulus arrival in normal subjects. In order to pursue these neuroscience objectives, new methods for treating MEG data were developed, implemented and used. These comprise: a) an improved parameterisation of signal power over regions of interest, b) the use of re-sampling strategies to achieve statistical assessment of spectral coefficients within subjects, and c) a prestimulus method for the study of face processing using a tailored state-space representation approach.
||1998 The Author
||Face perception; facial recognition; autism; neurolinguistics
||Science > Physical Sciences
||02 Dec 2009 11:57
||06 Mar 2014 04:47
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