Linear systems analysis for laminar fMRI: Evaluating BOLD amplitude scaling for luminance contrast manipulations

Jelle A van Dijk, Alessio Fracasso, Natalia Petridou, Serge O Dumoulin

Research output: Contribution to journalArticleAcademicpeer-review

26 Downloads (Pure)

Abstract

A fundamental assumption of nearly all functional magnetic resonance imaging (fMRI) analyses is that the relationship between local neuronal activity and the blood oxygenation level dependent (BOLD) signal can be described as following linear systems theory. With the advent of ultra-high field (7T and higher) MRI scanners, it has become possible to perform sub-millimeter resolution fMRI in humans. A novel and promising application of sub-millimeter fMRI is measuring responses across cortical depth, i.e. laminar imaging. However, the cortical vasculature and associated directional blood pooling towards the pial surface strongly influence the cortical depth-dependent BOLD signal, particularly for gradient-echo BOLD. This directional pooling may potentially affect BOLD linearity across cortical depth. Here we assess whether the amplitude scaling assumption for linear systems theory holds across cortical depth. For this, we use stimuli with different luminance contrasts to elicit different BOLD response amplitudes. We find that BOLD amplitude across cortical depth scales with luminance contrast, and that this scaling is identical across cortical depth. Although nonlinearities may be present for different stimulus configurations and acquisition protocols, our results suggest that the amplitude scaling assumption for linear systems theory across cortical depth holds for luminance contrast manipulations in sub-millimeter laminar BOLD fMRI.

Original languageEnglish
Article number5462
Number of pages15
JournalScientific Reports
Volume10
Issue number1
DOIs
Publication statusPublished - 1 Dec 2020

Fingerprint

Dive into the research topics of 'Linear systems analysis for laminar fMRI: Evaluating BOLD amplitude scaling for luminance contrast manipulations'. Together they form a unique fingerprint.

Cite this