Related Experiment Video
Updated: Jan 2, 2026
07:01
Head Implants for the Neuroimaging of Awake, Head-Fixed Rats
Published on: September 7, 2022
2.8K
Global brain signal in awake rats
Yuncong Ma1, Zilu Ma1, Zhifeng Liang1,2
1Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA.
Brain Structure & Function
|December 6, 2019
Summary
The global brain signal in awake rats, often ignored in resting-state functional MRI, involves coordinated activity in thalamo-cortical and hippocampo-cortical networks, revealing its neural basis.
Area of Science:
- Neuroscience
- Functional Magnetic Resonance Imaging (fMRI)
Background:
- The global brain signal (GBS) in resting-state fMRI (rsfMRI) is often treated as noise.
- Its neural underpinnings in awake rodents remain poorly understood, limiting interpretation of rsfMRI data.
Purpose of the Study:
- To investigate the neural basis of the GBS in awake rats using rsfMRI.
- To identify brain networks involved in generating the GBS in awake rodents.
Main Methods:
- Analysis of rsfMRI data from awake rats using single-echo (SE) and multi-echo (ME) echo planar imaging (EPI).
- Spatial pattern analysis of rsfMRI frames during GBS peaks.
- Simultaneous recording of hippocampal neural activity using GCaMP-based fiber photometry.
Main Results:
- rsfMRI GBS peaks showed co-activation in thalamo-cortical and hippocampo-cortical networks, and basal forebrain.
- De-noised ME-rsfMRI data confirmed these co-activation patterns.
- Hippocampal calcium activity significantly correlated with the global rsfMRI signal.
Conclusions:
- The GBS in awake rodents contains significant neural components.
- Coordinated activity within thalamo-cortical and hippocampo-cortical networks contributes to the GBS.
- This study provides crucial insights into the neural substrate of the GBS in awake rodents.
