The Effect Time Stressors Have On a Subject's Amount of Error in the Rod-and-Frame Test
In 1948, Witkin and Asch developed the rod-and-frame test to study the role of visual and gravitational cues in judging the visual vertical (Cian, 1997). Since the researchers have examined the many different possible outcomes of the orginal experiment They do this by adding, changing, or subtracting different parts of the experiment. Such variations include: the addition of strobe lighting on the frame (Cian, 1997), changes in the body posture of the subjects (Sigman, 1978), and the subtraction of an unlimited time restraint (Cian, 1995).
Cian and Raphel's experiment consisted of subjects viewing pictures flashed on a screen for a limited amount of time. The results supported the conclusion that time does have an effect on a subject's performance. Participants scores improved when their time was limited. The following study attempts to discover whether or not the knowledge of being timed (a time stressor) has an effect on a subject's accuracy of the rod placement, in Witkin and Asch's orginal rod-and-frame box.
Methods
Subject's consisted of twenty-five, Alma College student volunteers, ranging in age from eighteen to twenty-three.
The apparatus used was Witkin and Asch's original rod-frame box (Polymetric Company's Model: V-1260-AR). The frame was positioned at a right twenty-five degree angle and remained at that angle throughout the experiment. The rod angles were adjusted (in no particular order) to ten degrees left, eight degrees left, twenty degrees right, and fourteen degrees right.
The box was placed on the table and the subjects were seated in from of it. At this time instructions on how to adjust the rod were given. Subjects were informed that the object of the experiment was to rotate the handle of the appartus until they thought the rod was perfectly vertical.
Each subject participated in eight trials. Throughout the first four trials the subjects were unaware of the time factor. Their mind was set on achieving perfect accuracy, because that is what they were told their scores was based on. In the last four trials subjects were informed , and reminded throughout the experiment, that the amount of time it took them to complete the experiment would be factored into their scores. However, the participants were also reminded that they would still be scored on accuracy.
When the subject entered the room the rod was already set to the first angle. After each trial the subject was asked to remove their head from the fitted headrest, and to turn around. While the subject was not looking, the angle of the rod was altered. Upon the completion of each trial, both the time and the amount of error were recorded.
Results
After learning that time was a factor in thier scores, the subjects' amount of error did not increase or decrease in any major way. Although there was a slight decrease in the average effect on the subjects' amount of error, it was not enough of a difference to conclude that the time stressor had an effect on the subjects' amount of error. The results do show, however, the time stressor effected the subjects' placements of the rod (see figure 1). When the starting degree was negative (to the left) the participants turned the rod to the right. If the starting degree was positive (to the right) the subjects turned the rod to the left. The time stressor played an important role in how far to the right or left the subject moved the rod. When the participants were not under a time restraint, they did notmove the rod as far to the right or left as they did when they were under a time stressor. These results showed people under-compensated when there was no time restraint, and over-compensated when a time restraint was placed upon them.
Discussion
Many theories help to contribute some explination to this experiement's results. The first is the Confusion Theory. Although one would think the frame around the rod could be ignored, it cannot. After a few trials, the subject may grow accustomed to the tilt of the frame, causing its negative effect to decrease. This is known as adaptation, and could explain why the amount of error seemed to level off at the end of each section of trials.
There are also many everyday explinations for these results. The first explination could be the subjects' ability to work under pressure. All of the volunteers were college students, and each was accustomed to working under pressure. Being under a time restraint, subjects are in a hurry to finish each trial. They do not have time to second guess their answers. The lack of second guessing could be another explination for the differences in compensations. The subjects may have over-compensated due to the time stressor. They felt they did not have enough time to change their answers. The subjects were quick to assume the line was vertical, because they were no longer concentrating on the rod. Their focus was now on their times. Some of the subjects felt they needed to compete with other times. In thier minds they were in a competition with themselves and with all of the others. They were even less likely to readjust the rod, because that would take away from thier time. The more time they took, the lower they thought their score would be. The fear of being the slowest subject to complete each trial could be another explination for their amount of error.
Note that students over-compensated due to the time stressor. The students under-compensated when there was no time restraint placed upon them. This graph illustrates the differences in the degree of error, which occured due to the presence of a time stressor.
References
Cian, Corinne, Esquivie, Dominique, Barraud, Pierre-Alain, Raphel, Christian, & Ohlmann, Theophile. (1997) Strobe Frequency in the Rod and Frame Effect. Perceptual & Motor Skills, 85(1), 45-50.
Cian, Corrine, Raphel, Christian. (1995) The Role of Limited Time Exposure on the Rod and Frame Illusion: Vection or Orientation Contrast Effect?. Current Psychology of Cognition, 14(4), 367-386.
Sigman, Eric, Goodenough, Donald R., Flannagan Michael. (1978) Subjective Estimates of Body Tilt and the Rod-and-Frame Test. Perceptual & Motor Skills, 47(3, Pt 2), 1051-1056.
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