Cortex-wide BOLD fMRI activity reflects locally-recorded slow oscillation-associated calcium waves
- Johannes Gutenberg-University Mainz, Germany
- University Hospital Münster, Germany
Abstract
Spontaneous slow oscillation-associated slow wave activity represents an internally generated state which is characterized by alternations of network quiescence and stereotypical episodes of neuronal activity - slow wave events. However, it remains unclear which macroscopic signal is related to these active periods of the slow wave rhythm. We used optic fiber-based calcium recordings of local neural populations in cortex and thalamus to detect neurophysiologically defined slow calcium waves in isoflurane anesthetized rats. The individual slow wave events were used for an event-related analysis of simultaneously acquired whole-brain BOLD fMRI. We identified BOLD responses directly related to onsets of slow calcium waves, revealing a cortex-wide BOLD correlate: the entire cortex was engaged in this specific type of slow wave activity. These findings demonstrate a direct relation of defined neurophysiological events to a specific BOLD activity pattern and were confirmed for ongoing slow wave activity by independent component and seed-based analyses.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Fa474/5)
- Cornelius Faber
Deutsche Forschungsgemeinschaft (SFB 1080)
- Albrecht Stroh
Deutsche Forschungsgemeinschaft (SFB 1193)
- Albrecht Stroh
Deutsche Forschungsgemeinschaft (SPP 1665)
- Albrecht Stroh
Focus Program translational Neurosciences
- Miriam Schwalm
- Albrecht Stroh
Interdisciplinary Center for Clinical Research Münster (Fa3/1603,PIX)
- Cornelius Faber
Excellence Cluster Cells in Motion (EXEC 1003)
- Cornelius Faber
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal husbandry and experimental manipulation were carried out according to animal welfare guidelines of the Westfalian Wilhelms-University and the Johannes Gutenberg-University Mainz and were approved by the Landesamt für Natur-, Verbraucher- und Umweltschutz Nordrhein-Westfalen, Recklinghausen, Germany (animal protocol number: 84-02.04.2015.A427), and the Landesuntersuchungsamt Rheinland-Pfalz, Koblenz, Germany (animal protocol number: G 14-1-040). All surgery was performed under deep isoflurane anesthesia.
Copyright
© 2017, Schwalm et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Cortex-wide BOLD fMRI activity reflects locally-recorded slow oscillation-associated calcium waves
eLife 6:e27602.
https://doi.org/10.7554/eLife.27602
Further reading
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