Abstract #0210
fMRI post-stimulus undershoots in visual cortex are neuronal in origin
Karen J Mullinger 1,2 , Matthew Cherukara 1 , Susan T Francis 1 , and Stephen D Mayhew 2
1
SPMIC, School of Physics and Astronomy,
University of Nottingham, Nottingham, Nottinghamshire,
United Kingdom,
2
BUIC,
School of Psychology, University of Birmingham,
Birmingham, West Midlands, United Kingdom
The fMRI post-stimulus undershoot is widely observed but
its origins remain unclear. We recorded EEG-BOLD-ASL
responses to 10s-duration flickering and static visual
checkerboard stimuli and show that the amplitude of both
the BOLD and CBF post-stimulus undershoots in V1 are
negatively correlated with the 10-20s post-stimulus
power of the occipital EEG alpha (8-13Hz) oscillation.
In addition, flicker trials resulted in both
significantly larger fMRI undershoots and significantly
higher post-stimulus alpha power responses than static
trials. These results provide further evidence that the
fMRI undershoot arises from a neuronal mechanism and
comprises a unique feature of brain activity.
How to access this content:
For one year after publication, abstracts and videos are only open to registrants of this annual meeting. Registrants should use their existing login information. Non-registrant access can be purchased via the ISMRM E-Library.
After one year, current ISMRM & ISMRT members get free access to both the abstracts and videos. Non-members and non-registrants must purchase access via the ISMRM E-Library.
After two years, the meeting proceedings (abstracts) are opened to the public and require no login information. Videos remain behind password for access by members, registrants and E-Library customers.
Click here for more information on becoming a member.
