Abstract:
:The electrophysiological basis for higher brain activity during rest and internally directed cognition within the human default mode network (DMN) remains largely unknown. Here we use intracranial recordings in the human posteromedial cortex (PMC), a core node within the DMN, during conditions of cued rest, autobiographical judgments, and arithmetic processing. We found a heterogeneous profile of PMC responses in functional, spatial, and temporal domains. Although the majority of PMC sites showed increased broad gamma band activity (30-180 Hz) during rest, some PMC sites, proximal to the retrosplenial cortex, responded selectively to autobiographical stimuli. However, no site responded to both conditions, even though they were located within the boundaries of the DMN identified with resting-state functional imaging and similarly deactivated during arithmetic processing. These findings, which provide electrophysiological evidence for heterogeneity within the core of the DMN, will have important implications for neuroimaging studies of the DMN.
journal_name
Proc Natl Acad Sci U S Aauthors
Dastjerdi M,Foster BL,Nasrullah S,Rauschecker AM,Dougherty RF,Townsend JD,Chang C,Greicius MD,Menon V,Kennedy DP,Parvizi Jdoi
10.1073/pnas.1017098108subject
Has Abstractpub_date
2011-02-15 00:00:00pages
3023-8issue
7eissn
0027-8424issn
1091-6490pii
1017098108journal_volume
108pub_type
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