Month: January 2024
-
Vision and Flickering States
As soon as you open your eyes, the regions of activity in the default mode network begin to decrease activity. Well, that’s exactly what happens to alpha activity on the EEG. We say alpha attenuates, which means decreases amplitude. At the same time this network turns off. Should you begin working on a task, say…
-
Anatomy of Default Mode
I have included the parts of the brain that are active, mainly consuming Oxygen at which time the subjects are in a state of awake, eyes closed, restful waking. Images are a sort of average over many individual subjects. The red areas are mostly in the midline in the front of the brain, the Medial…
-
Default State: EEG
I came of age in neurology before clinicians had the means to show activity in specific parts of the brain as can be done now with PET and fMRI. In the late 20th century neurologists discussed restful eyes-closed waking. We used the EEG to follow alterations in mental states. Being any movement at all would…
-
States
The first mental state is the Default Mode Network. This symmetric anatomic brain area found on brain metabolic studies such as fMRI and PET outlined by Marcus Raichle et al 2001. Their human subjects were scanned, eyes closed, generally thinking of nothing. When I first came upon this description I thought, that is exactly the…