Algorithms for detection and suppression of hemodynamic oscillations (HDO).
Arterial vasodilation caused by cerebral vasomotion can cause oscillations of the blood flow. fMRI measurements of medetomidine sedated animals show oscillations with a characteristic frequency around 0.2 Hz. These hemodynamic oscillations (HDO) constitute a physiological noise source for fMRI measurements and affect analysis of fMRI data. The presented algorithms detect and suppress HDO.
HDO_detection
The script ‘HDO_detection_master’ detects oscillations and delivers the output whether an inserted time course contains HDO. An fMRI signal time course and its temporal resolution are to insert as one-dimensional double arrays (see example data).
HDO_suppression
The script ‘HDO_suppression_master’ suppresses HDO from an inserted time course. An fMRI signal time course and its temporal resolution are to insert as one-dimensional double arrays (see example data).
Additionally, the script ‘HDO_suppr_voxelwise_master.m’ enables the voxel-wise application of the HDO suppression algorithm to a 4D-fMRI dataset in the NIfTI format.
The scripts run on MATLAB 2017b and all later versions.
These scripts were created by your colleagues. Please cite the article in which HDO algorithms were described:
Lambers et al. Frontiers in neuroscience. 2023 Feb; 17: 1064000. doi:10.3389/fnins.2023.1064000
https://www.frontiersin.org/articles/10.3389/fnins.2023.1064000/full