Search results
Results from the WOW.Com Content Network
This alpha activity is centered in the occipital lobe, [22] [23] although there has been speculation that it has a thalamic origin. [24] The second occurrence of alpha wave activity is during REM sleep. As opposed to the awake form of alpha activity, this form is located in a frontal-central location in the brain.
During wakefulness, theta oscillations have been often related to successful performance in memory tasks, and cued memory reactivations during sleep have been showing that theta activity is significantly stronger in subsequent recognition of cued stimuli as compared to uncued ones, possibly indicating a strengthening of memory traces and ...
[151] [152] Ekirch attributes the change to increases in "street lighting, domestic lighting and a surge in coffee houses," which slowly made nighttime a legitimate time for activity, decreasing the time available for rest. [152] Today in most societies people sleep during the night, but in very hot climates they may sleep during the day. [153]
When an individual first begins to sleep, stage 1 is entered, marked by the presence of some theta activity, which indicates that the firing of neurons in the neocortex is becoming more synchronized, as well as alpha wave activity (smooth electrical activity of 8–12 Hz recorded from the brain, generally associated with a state of relaxation).
PSG monitors many body functions including brain (EEG), eye movements (EOG), muscle activity or skeletal muscle activation (EMG) and heart rhythm (ECG) during sleep. Electroencephalography (EEG) EEG records the brain's spontaneous electrical activity over a short period of time, usually 20–40 minutes, as recorded from multiple electrodes on ...
Then those cycles are broken into stages within two categories: NREM sleep (non-rapid eye movement sleep) and REM sleep (also known as rapid eye movement sleep). Your brain activity changes during ...
[23] Furthermore, they suggest that the alpha rhythm could be the "natural resonance frequency of the visual cortex during the waking state, whereas the alpha activity that appears in the drowsiness period at sleep onset could be indexing the hypnagogic imagery self-generated by the sleeping brain, and a phasic event in the case of REM sleep."
The importance of PGO waves during REM sleep also aids the idea of PGO waves as a signal that a person is dreaming. [22] Since dreaming occurs during REM sleep, the PGO waves are theorized to be the signals that make the brain start to recount the experiences from the previous day.