Biomedical Engineering Reference
In-Depth Information
impaired brain function and behavior during seizures caused by
abnormally increased activity, abnormally decreased activity, or
both? There remains much to learn about spike-and-wave dis-
charges through the use of fMRI. Behavioral tests in both humans
and animals must be added to simultaneous EEG-fMRI in order
to fully correlate behavioral deficits with the anatomy of fMRI
signal changes
(28, 68)
. More sophisticated analytic techniques
must be developed in order to explore the fMRI time-course,
as well as to better correlate the electrophysiology data with
the hemodynamic response measured by fMRI data. Long-range
network changes can be further investigated using resting func-
tional connectivity studies based on the fMRI signals, and using
technology such as diffusion tensor imaging (DTI). Numerous
measurements, including CBF, CBV, and CMRO2, have yet to
be undertaken in human patients or animal models to more
fully understand the fundamental neuroenergetics of SWD. fMRI
investigation of additional rat, mouse, and feline models of SWD
(23, 94, 95)
can also provide a more general understanding of
SWD mechanisms. Finally, these techniques should be applied to
understand developmental changes that occur during the devel-
opment of epilepsy. Neuroimaging has the potential to provide
a safe, non-invasive biomarker for epileptogenesis and its pre-
vention, and could ultimately be used as a way to monitor the
success of treatments aimed at suppressing spike-wave develop-
ment
(27)
. Much exciting research remains to be done using
fMRI to investigate the unknowns of spike-and-wave discharges
and epilepsy in the future.
Acknowledgments
We thank Mi Hae Chung for assistance with the figures. This
work was supported by NIH R01 NS055829, R01 NS049307,
P30 NS052519, the Donaghue Foundation, and by the Betsy and
Jonathan Blattmachr family.
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