Showing papers on "Time perception published in 1979"

The perception of time

Abstract: The present paper organizes and evaluates selected portions of the time perception literature. Emphasis is on data and theory concerned primarily with judgments of brief temporal intervals. Research concerning the psychophysical law for time, Weber’s law, the time-order error, and the role of nontemporal information is evaluated. This is followed by a consideration of current, quantitatively oriented, theoretical formulations for time perception.

EEG alpha biofeedback and time perception.

Abstract: Attempts to relate psychological time to physiological variables date to Hoagland's ( 2 ) studies which developed the concept of an "internal clock" against whose "ticks" psychological time is experienced. Several candidates for the physiological pacemaker have been proposed including EEG cortical events, in particular the EEG alpha rhythm (5),; +e actual evidence on the alpha rhythm has been mixed and complicated by the lim~tatlons of correlational designs ( 3 ) and use of invasive .techniques such as drugs ( I ) , and photic driving ( 4 ) . With these problems in mind, EEG alpha biofeedback was used to manipulate EEG alpha to observe effects on time perception. Each of the 12 participants sat, eyes open, in a dimly lit room for 12 identical 1-hr. sessions. An Autogenic Systems Model 120 EEG biofeedback device detected 8to 13-Hz activity between active electrodes at T3-Ol. Three consecutive 8to 13-Hz waves were required to deliver a feedback tone through a speaker. After a brief baseline, there were four 5-min. biofeedback segments of alternating EEG alpha enhancement and suppression. An identical 20-min. period followed except a time-estimation task with intervals of from 30 to 100 sec. was superimposed on the biofeedback tasks. The experimenter said "start" to initiate each interval to be estimated and "stop" at the end, at which time the participant gave a verbal estimate of the interval in seconds. The percent of the time criterion EEG alpha was present was recorded for each time estimation trial. There was over-all control of EEG alpha, with means of 81.3% alpha time in alpha enhancement segments vs 32.8% in suppression (Fu" = 65.75, p < .OOl). With time estimates expressed as percentages of the actual intervals, there was no effect of interval length on time estimates ( p > . l o ) . Although time estimates became shorter across sessions ( p < .005), this effect did not interact with biofeedback conditions. Time estimates were longer during biofeedback enhanced alpha, 11896, as compared to 107% of the actual intervals during alpha suppression (F,,l, = 7.40, 9 < .01). Correlations between time estimates and concurrent alpha within biofeedback conditions yielded no significant relationships. The shorter time esrimates during decreased alpha -slowing of psychological time with increased EEG activation-are contrary to EEG pacemaker theories. The present results may be related to an unmonitored physiological pacemaker whose activiry was indirectly influenced by the alpha biofeedback or to associated changes in conscious experience. There is as yet no clear support for a simple pacemaker mechanism in the brain. reflected in the EEG alpha rhythm, whose "ticks" mark off psychological time. Biofeedback is a promising. non-invasive, method of investigating the effects of physiological variables on the perception of duration.

The indifference interval and the filled duration illusion : a study of temporal experience with durations between 200 and 1100 msec

Abstract: Three experiments investigated phenomena related to the concept of the indifference interval and the filled duration illusion from an information processing viewpoint. In Experiment 1 an increasing linear function between nontemporal stimulus information and subjective duration was found when subjects judged 300 and 330 msec durations, but not 500 and 550 msec durations. In Experiment 2 an additional level of nontemporal stimulus extent was used, and a quadratic function between nontemporal events and duration judgments was found. In Experiment 3 a wider range of durations was used, but with the same number of levels of nontemporal stimuli employed in Experiment 1. The relation between nontemporal stimuli and duration judgments returned to an increasing linear function. In all three experiments the effects on nontemporal stimuli tended to disappear as the durations became longer. STATEMENT OF PERMISSION TO COPY In presenting this thesis in partial fulfillment of the requirements for an advanced degree at Montana State University, I agree that the library shall make it freely available for inspection. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by my major professor, or, in his absence, by the Director of Libraries. It is understood that any copying or publication of this thesis for financial gain shall not be allowed without my written