Document Type



Doctor of Philosophy



First Adviser

Wuest, Francis J.


The present study is an attempt to provide more than correlative evidence that brain rhythms actively influence the perception of temporal. duration. Brain rhythms were manipulated using intermittent photic and auditory stimulation. EEG recordings during experimental trials demonstrate the effects of these manipulations during production of a ten second duration. Various patterns of synchrony and synchrony in brain activity can be produced by pairing frequencies of afferent activity With a subject's underlying spontaneous activity. Changes also occur over time in the experimental setting. This latter change may be due to changes in arousal or activation level. Subjects produced a time interval under varying conditions of intermittent and steady stimulation over forty-five trials. The results showed that times lengthen over sequential trials, and that there is an additional lengthening effect when the pattern of cortical activity is synchronous. It is concluded that the pattern of cortical activity as evidenced in an EEG record has a significant effect on the perception of time. A model of the physiological systems active in such activity is suggested.