A Parametric Manipulation of Factors Affecting Task-induced Deactivation in Functional Neuroimaging
Journal of Cognitive Neuroscience
Deactivation of Sensory-Specific Cortex by Cross-Modal Stimuli
Journal of Cognitive Neuroscience
Conceptual Processing during the Conscious Resting State: A Functional MRI Study
Journal of Cognitive Neuroscience
The Cerebral Response during Subjective Choice with and without Self-reference
Journal of Cognitive Neuroscience
Deactivations, Global Signal, and the Default Mode of Brain Function
Journal of Cognitive Neuroscience
Going awol in the brain: Mind wandering reduces cortical analysis of external events
Journal of Cognitive Neuroscience
Journal of Biomedical Imaging - Recent Advances in Neuroimaging Methodology
Cognitive and emotional modulation of brain default operation
Journal of Cognitive Neuroscience
Unification of speaker and meaning in language comprehension: An fmri study
Journal of Cognitive Neuroscience
Spatio-temporal brain dynamics mediating post-error behavioral adjustments
Journal of Cognitive Neuroscience
Hippocampal involvement in processing of indistinct visual motion stimuli
Journal of Cognitive Neuroscience
Group Study of Simulated Driving fMRI Data by Multiset Canonical Correlation Analysis
Journal of Signal Processing Systems
Dynamic causality analysis on default mode network
AICI'12 Proceedings of the 4th international conference on Artificial Intelligence and Computational Intelligence
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Deactivation refers to increased neural activity during lowdemand tasks or rest compared with high-demand tasks. Several groups have reported that a particular set of brain regions, including the posterior cingulate cortex and the medial prefrontal cortex, among others, is consistently deactivated. Taken together, these typically deactivated brain regions appear to constitute a default-mode network of brain activity that predominates in the absence of a demanding external task. Examining a passive, block-design sensory task with a standard deactivation analysis (rest epochs vs. stimulus epochs), we demonstrate that the default-mode network is undetectable in one run and only partially detectable in a second run. Using independent component analysis, however, we were able to detect the full default-mode network in both runs and to demonstrate that, in the majority of subjects, it persisted across both rest and stimulus epochs, uncoupled from the task waveform, and so mostly undetectable as deactivation. We also replicate an earlier finding that the default-mode network includes the hippocampus suggesting that episodic memory is incorporated in default-mode cognitive processing. Furthermore, we show that the more a subject's default-mode activity was correlated with the rest epochs (and "deactivated" during stimulus epochs), the greater that subject's activation to the visual and auditory stimuli. We conclude that activity in the default-mode network may persist through both experimental and rest epochs if the experiment is not sufficiently challenging. Time-series analysis of default-mode activity provides a measure of the degree to which a task engages a subject and whether it is sufficient to interrupt the processes—presumably cognitive, internally generated, and involving episodic memory—mediated by the default-mode network