Testing hypotheses of context-dependent, distributed, and non-hierarchical neural representation using hypermodal MRI

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The project aims to evaluate specific computational models of context-dependent auditoryand visual representation, attention, and integration using a new 'hypermodal' MRI dataset.The MOVIE II project uses high temporal and spatial resolution functional MRI tocomprehensively map out participants' blood-oxygen-level-dependent responses to a fulllength movie, as well as more controlled visual, auditory, and somatosensory mappingstimuli, brain-region-specific hemodynamic responses, high-resolution maps ofmacromolecular, water, and iron content, and time-locked recordings of participants'eyegaze, and physiology.The PhD student will evaluate the explanatory power of models that take into accounttemporal buildup of sensory information within and across modalities, as well as moreabstract characterizations, such as event flow and the establishment of musical motifs orphrasal tension. In Year 2 of the PhD, under the supervision of Skipper and Dick, the studentwill build explanatory computational models for fMRI activity that build in an increasingdegree of contextual modulation on acoustic and visual features, and test these infunctionally and myeloarchitectonically defined brain regions that are at different tiers inputative cortical hierarchies. In Year 3-4, supervised by Tierney, Skipper, and Dick, thestudent will also conduct a 'spin-off' EEG study, where participants will again view the samemovie used in the MOVIE II database.This new dataset will be used to generate temporalresponse functions to a subset of the features used for fMRI analyses; these will in turngenerate more temporally detailed estimates of neural responses that will be used to furthercondition the initial fMRI models of the MOVIE II data. The student will also design and runsmall-N fMRI studies that vary the linguistic or acoustic content of the movie presented totest hypotheses about the modulation of perceptual processing by more abstract cognitiveconstructs.