Point-spread function of the BOLD response across columns and cortical depth in human extra-striate cortex

Fracasso, A. , Dumoulin, S. O. and Petridou, N. (2021) Point-spread function of the BOLD response across columns and cortical depth in human extra-striate cortex. Progress in Neurobiology, 202, 102034. (doi: 10.1016/j.pneurobio.2021.102034) (PMID:33741401)

Abstract

Columns and layers are fundamental organizational units of the brain. Well known examples of cortical columns are the ocular dominance columns (ODCs) in primary visual cortex and the column-like stripe-based arrangement in the second visual area V2. The spatial scale of columns and layers is beyond the reach of conventional neuroimaging, but the advent of high field magnetic resonance imaging (MRI) scanners (UHF, 7 Tesla and above) has opened the possibility to acquire data at this spatial scale, in-vivo and non-invasively in humans. The most prominent non-invasive technique to measure brain function is blood oxygen level dependent (BOLD) fMRI, measuring brain activity indirectly, via changes in hemodynamics. A key determinant of the ability of high-resolution BOLD fMRI to accurately resolve columns and layers is the point-spread function (PSF) of the BOLD response in relation to the spatial extent of neuronal activity. In this study we take advantage of the stripe-based arrangement present in visual area V2, coupled with sub-millimetre anatomical and gradient-echo BOLD (GE BOLD) acquisition at 7 T to obtain PSF estimates and along cortical depth in human participants. Results show that the BOLD PSF is maximal in the superficial part of the cortex (1.78 mm), and it decreases with increasing cortical depth (0.83 mm close to white matter).

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fracasso, Dr Alessio
• Authors: Fracasso, A., Dumoulin, S. O., and Petridou, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience
• Journal Name: Progress in Neurobiology
• Publisher: Elsevier
• ISSN: 0301-0082
• ISSN (Online): 1873-5118
• Published Online: 16 March 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Progress in Neurobiology 101: 102034
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
303685		Stable perception of external stimuli over time: oculo-motor and visual processing mechanisms	Alessio Fracasso	Biotechnology and Biological Sciences Research Council (BBSRC)	BB/S006605/1	NP - Centre for Cognitive Neuroimaging (CCNi)