PT  - JOURNAL ARTICLE
AU  - Garrett, Douglas D.
AU  - Kovacevic, Natasa
AU  - McIntosh, Anthony R.
AU  - Grady, Cheryl L.
TI  - Blood Oxygen Level-Dependent Signal Variability Is More than Just Noise
AID  - 10.1523/JNEUROSCI.5166-09.2010
DP  - 2010 Apr 07
TA  - The Journal of Neuroscience
PG  - 4914--4921
VI  - 30
IP  - 14
4099  - http://www.jneurosci.org/content/30/14/4914.short
4100  - http://www.jneurosci.org/content/30/14/4914.full
SO  - J. Neurosci.2010 Apr 07; 30
AB  - Functional magnetic resonance imaging (fMRI) research often attributes blood oxygen level-dependent (BOLD) signal variance to measurement-related confounds. However, what is typically considered “noise” variance in data may be a vital feature of brain function. We examined fMRI signal variability during fixation baseline periods, and then compared SD- and mean-based spatial patterns and their relations with chronological age (20–85 years). We found that not only was the SD-based pattern robust, it differed greatly, both spatially and statistically, from the mean-based pattern. Notably, the unique age-predictive power of the SD-based pattern was more than five times that of the mean-based pattern. This reliable SD-based pattern of activity highlights an important “signal” within what is often considered measurement-related “noise.” We suggest that examination of BOLD signal variability may reveal a host of novel brain-related effects not previously considered in neuroimaging research.