Temporal and Spatial Factors
Posted on
November 3, 2023
Let's learn all the facts about a brain pattern called
Temporal and Spatial Factors
!
Temporal and Spatial Factors
Yamada, Thoru, and Elizabeth Meng. Practical Guide for Clinical Neurophysiologic Testing: EEG. Available from: Wolters Kluwer, (2nd Edition). Wolters Kluwer Health, 2017. Greenfield, John, L. et al. Reading EEGs: A Practical Approach. Available from: Wolters Kluwer, (2nd Edition). Wolters Kluwer Health, 2020.
In addition to examining the amplitude, frequency, and waveform of the given EEG activity, it is equally important to assess the temporal factor and the spatial factor of the activity. So, what does that even mean?
It is well agreed that EEG has excellent temporal resolution reflecting dynamic brain function in terms of milliseconds (timing). Temporal factors are also important in distinguishing normal from abnormalactivity.
Example of a temporal factor: paroxysmal bursts are a physiological pattern in sleep or during an arousal period but if a similar paroxysmal burst appears in the awake state, it would be abnormal.
Spatial and anatomical resolution for localization of an electrical source of a given activity are determined by location.
Example of a spatial factor: a vertex sharp wave is a sharply contoured transient spatially maximum at the midline (vertex) with symmetrical spread to the parasagittal regions in normal sleep. But if similar discharges appear in only one hemisphere or consistently asymmetric, they could represent an abnormal pattern.