A distinctive electrographic entity: bursts of rhythmical temporal theta.

The goal of this study was to investigate the electro-clinical correlations of a distinctive EEG pattern: bursts of rhythmic temporal theta (BORTT). Patients (260) with this pattern were compared to 4 control groups. The peak age in patients with BORTT was in the 50's, appearing especially in black females. The incidence of this pattern in our randomly selected patient group was significantly greater than in a group without evidence of organic cerebral disease. BORTT had a marked preference for the left temporal area (93%), as opposed to the right (30%). In 1/3 of patients, no other EEG finding appeared and in an equal number other mild slow wave abnormalities were seen. Evidence of some kind of vascular disorder (33%) or trauma (16%) was found in nearly 1/2 of the BORTT patients, but the pattern is likely associated with may kinds of etiologies. In conclusion, BORTT likely represents a mild slow wave abnormality, especially of the left temporal lobe in adults, indicating a slight neurophysiological disturbance of varying etiology, but often of vascular origin.