I'm not sure how I can use this information but it's interesting.
http://www.pnas.org/content/109/14/5487
Abstract
The brain is the body's largest energy
consumer, even in the absence of demanding tasks. Electrophysiologists
report on-going
neuronal firing during stimulation or task in
regions beyond those of primary relationship to the perturbation.
Although the
biological origin of consciousness remains elusive,
it is argued that it emerges from complex, continuous whole-brain
neuronal
collaboration. Despite converging evidence
suggesting the whole brain is continuously working and adapting to
anticipate and
actuate in response to the environment, over the
last 20 y, task-based functional MRI (fMRI) have emphasized a
localizationist
view of brain function, with fMRI showing only a
handful of activated regions in response to task/stimulation. Here, we
challenge
that view with evidence that under optimal noise
conditions, fMRI activations extend well beyond areas of primary
relationship
to the task; and blood-oxygen level-dependent
signal changes correlated with task-timing appear in over 95% of the
brain for
a simple visual stimulation plus attention control
task. Moreover, we show that response shape varies substantially across
regions, and that whole-brain parcellations based
on those differences produce distributed clusters that are anatomically
and functionally meaningful, symmetrical across
hemispheres, and reproducible across subjects. These findings highlight
the
exquisite detail lying in fMRI signals beyond what
is normally examined, and emphasize both the pervasiveness of false
negatives,
and how the sparseness of fMRI maps is not a result
of localized brain function, but a consequence of high noise and overly
strict predictive response models.
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