2. Overview of Talk
Conclusion
Methodological
Recipe and Caveats
Background
Future directions
5. Conclusion
Resting state networks are:
Highly robust across cultures, laboratories,
methods
Localized to gray matter and predicted by
tractography
Found in fMRI, EEG, MEG, and intracranial
recordings
Implicated in information processing, multi-
tasking, memory, learning, development and
emotion
Easy to obtain, easy to analyze, and damn
interesting
Human connectomics - dont get left behind!
8. simple recipe for rsfMRI
5-7 minutes of rest
Fixation, or no-fixation.
Place at beginning of scan
Duplicate for maximum effect
Extra ROI timeseries/foci
ICA vs a priori seed-r
Regression with whole brain and/or task
12. Pre-processing
Band-pass filter:
remove constant offsets
and linear trends,
retain <0.08 Hz
Regression of nuisance
variables; motion,
global signal, average
lateral ventricle, deep
cerebral white matter.
22. A little history
The default mode of brain function originally proposed by
Raichle and Fox (2001)
Attracted initial controversy; why we should resist the baseline
Has since exploded, evolved into the functional and human
connectome projects.
Confusion springs from a failure to distinguish between psychological,
physiological and anatomical accounts. The Rt. Hon. Lord Brain (Brain 1969)
From a brief history of the DMN (Raichle, 2007)
25. Resting States are Predicted by
Structure
Predicting human resting-state
functional connectivity from structural
connectivity
1. C. J. Honeya, O. Spornsa,1, L. Cammounb, X. Gigandetb, J. P.
Margulies et al. (2009) Thiranb, R. Meulicand P. Hagmannb,c
31. To be safe
If you want to look at anti-r networks:
Record respiration
Avoid global signal regression
Include a task likely to engage CEN and SAL networks.
32. A Default Mode?
Marianas Trench Argument: Dont conflate structure with
content!
Rumination, introspection, social cognition
Free-energy
Consciousness?
33. Picking apart DMN
Although exact function remains unclear, DMN connectivity at rest and
during task-processing now implicated in:
Schizophrenia
OCD
Autism
ADHD
Levels of consciousness
Task-irrelevant thoughts
34. Measuring the Default
The Resting State Questionnaire (RSQ)
Experience Sampling (Schooler et al)
Differential engagement by task
Correlation with individual differences
38. Real Conclusion
There is simply too much multi-modal, multi-cultural evidence to
dismiss slow-wave processing as a feature of mammalian brains
Simple stories; DMN as consciousness, pure anti-correlation,
1:1 mapping between structure and function = FAIL
If you are spending the time and energy doing fMRI, you might
as well spend 5-7 minutes at rest.