Albers, Franziska ; Wachsmuth, Lydia ; Schache, Daniel; Lambers, Henriette; Faber, Cornelius: Functional MRI Readouts From BOLD and Diffusion Measurements Differentially Respond to Optogenetic Activation and Tissue Heating
Inhalt
- Materials and Methods
- Animal Preparation
- fMRI
- Experiment 1: Identifying the Threshold for Heating Artifacts
- Experiment 2: High-Intensity Light Application
- Experiment 3: Optogenetic and Electric Forepaw Stimulation
- Analysis
- Results
- Threshold for Heating Artifacts
- Diffusion fMRI With High Temporal Resolution Is Feasible
- Spatial Pattern and Temporal Shape of Signal Changes Upon High-Intensity Light Application
- Similar Signal Changes Due to Tissue Heating Occur in vivo and ex vivo
- Signal Changes Upon Tissue Heating Are Dominated by T2*-Effects
- Light Application Can Reduce the BOLD Signal Already at Low Light Intensities
- Signal Changes in Diffusion fMRI Are Similar to Those in GE-/SE-BOLD fMRI
- Neuronal Activation and Tissue Heating Lead to ADC Changes With Opposite Sign
- Discussion
- Heating Artifacts Have a Strong T2* Contribution
- Light Application Can Diminish BOLD Responses Upon Optogenetic Stimulation
- Signal Changes in Diffusion-Type Measurements Are Not a Heating Effect but Depend on Changes in Diffusion, T2 and T2*
- Conclusion
- Data Availability Statement
- Ethics Statement
- Author Contributions
- Funding
- Supplementary Material
- References