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Full-Text Articles in Neuroscience and Neurobiology

Optimizing Preprocessing Of Fmri Data To Maximize Correspondence Of Functional Anatomy Across Individuals, Nargess Ghazaleh Sep 2020

Optimizing Preprocessing Of Fmri Data To Maximize Correspondence Of Functional Anatomy Across Individuals, Nargess Ghazaleh

Electronic Thesis and Dissertation Repository

In movie-activation fMRI, intersubject correlation (ISC) indicates a functional correspondence across viewers. Brains di↵er in shape; spatial normalization and smoothing enhance inter-subject functional overlap. We compare three normalization methods and six smoothing levels to discover which method yields the best functional overlap, indexed by ISC. This is key to optimizing data analysis in clinical studies using movie-activation fMRI in future. In a 3T scanner, 44 healthy subjects watched an 8-min movie. Both normalization and smoothing a↵ected the strength and extent of the ISC. ISC values were more robust for ANTs and DARTELthanforSPM12andwere(asymptotically)thestrongestat12mmsmoothing. When image data are preprocessed with high-dimensional volumetric …


The Temporal Dynamics Of Ensemble Perception, Michael L. Epstein Sep 2020

The Temporal Dynamics Of Ensemble Perception, Michael L. Epstein

Dissertations, Theses, and Capstone Projects

The striking disparity between the subjective richness of experience and the considerable limitations of perceptual processing has emerged as an essential, enduring question in both vision science and philosophy of mind. A potential solution to this issue is ensemble perception: the ability for the visual system to compute the statistical summaries of object groups, effectively compressing an otherwise overwhelming amount of information. Previous work has supported that ensemble statistics can be perceived quickly and accurately for a wide range of object features. This has motivated models of ensemble perception as an early process in vision, providing an initial sense of …