title: Comparison of functional thalamic segmentation from seed-based analysis and ICA.
abstract: Information flow between the thalamus and cerebral cortex is a crucial component of adaptive brain function, but the details of thalamocortical interactions in human subjects remain unclear. The principal aim of this study was to evaluate the agreement between functional thalamic network patterns, derived using seed-based connectivity analysis and independent component analysis (ICA) applied separately to resting state functional MRI (fMRI) data from 21 healthy participants. For the seed-based analysis, functional thalamic parcellation was achieved by computing functional connectivity (FC) between thalamic voxels and a set of pre-defined cortical regions. Thalamus-constrained ICA provided an alternative parcellation. Both FC analyses demonstrated plausible and comparable group-level thalamic subdivisions, in agreement with previous work. Quantitative assessment of the spatial overlap between FC thalamic segmentations, and comparison of each to a histological "gold-standard" thalamic atlas and a structurally-defined thalamic atlas, highlighted variations between them and, most notably, differences with both histological and structural results. Whilst deeper understanding of thalamocortical connectivity rests upon identification of features common to multiple non-invasive neuroimaging techniques (e.g. FC, structural connectivity and anatomical localisation of individual-specific nuclei), this work sheds further light on the functional organisation of the thalamus and the varying sensitivities of complementary analyses to resolve it.
authors.affiliation: School of Psychology, University of Birmingham, Birmingham, United Kingdom. Electronic address: j.hale.1@bham.ac.uk.
authors.forename: Joanne R
authors.initials: JR
authors.lastname: Hale
authors.affiliation: School of Psychology, University of Birmingham, Birmingham, United Kingdom.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Mayhew
authors.affiliation: School of Psychology, University of Birmingham, Birmingham, United Kingdom; Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom.
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Mullinger
authors.affiliation: School of Psychology, University of Birmingham, Birmingham, United Kingdom.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Wilson
authors.affiliation: Institute of Digital Healthcare, WMG, University of Warwick, Coventry, United Kingdom.
authors.forename: Theodoros N
authors.initials: TN
authors.lastname: Arvanitis
authors.affiliation: Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom.
authors.forename: Susan T
authors.initials: ST
authors.lastname: Francis
authors.affiliation: School of Psychology, University of Birmingham, Birmingham, United Kingdom.
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Bagshaw
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013788:Thalamus / Q000502:physiology*; D055815:Young Adult
keywords: Functional connectivity; ICA; Resting state; Thalamocortical; Thalamus; fMRI