Human satiety and hunger are usually measured by observations of eating behavior or by verbal reports. Neither of these seems to be an objective method of measurement. Some studies have indicated that pupil responses to pictures of food may correspond with interest in food. The objective of this study was to determine the feasibility of using pupil responses to food pictures to measure human satiety. Pupil sizes of 17 women, mean age 25.3 years, were measured as the women watched slide pictures of food before and after eating a high carbohydrate breakfast. Each subject participated in one to four experiments. Plasma glucose values were measured with the AutoAnalyzer ferricyanide method. Samples were taken during the fasting state and at approximately 30, 45, and 60 minutes after a breakfast which contained one gram of carbohydrate per kilogram of subject's body weight. Pupil sizes were measured with equipment which included an infra-red sensitive television camera. Pupil responses to pictures of food were compared to pupil responses to control pictures of non-food items. The differences of the changes in pupil responses before and about 50 minutes after eating were compared to several variables to determine correlation coefficients. Plasma glucose values were found to be similar to those in other studies in which subjects ingested glucose solutions. Fasting glucose values were similar for all subjects using oral contraceptives and those who were not. Samples taken at approximately 60 minutes showed a higher plasma glucose level (118.6 mg./100 ml. [plus or minus] 30.7) for oral contraceptive users than for non-users (95.2 mg./100 ml. [plus or minus] 15.4). Several significant correlations were found between changes in pupil response to food pictures after eating and some of the considered variables. Blue-eyed subjects had increased pupil responses to pictures of peaches and crackers, and brown-eyed subjects had decreased responses to these pictures (peaches, p<.05; crackers, p<02). Subjects who usually ate all they wanted had increased responses to pictures of crackers, and subjects who restrained their eating had decreased responses to these pictures (p<.02). Increasing rate of the fall in plasma glucose correlated with smaller or negative changes in response to pictures of eggs and sausage, cookies, and jelly on toast. Decreasing rapidity of the plasma glucose fall was associated with greater responses to these pictures (eggs and sausage, p<.05; cookies, p<.02; jelly on toast, p<.05). Other significant correlations were also found for changes in pupil responses to various food pictures when the variables of time of day, experiment number, body mass index and percentage of body fat (as determined by skinfold measurements) were considered, but there is some doubt about the validity of these correlations. No correlations were significant when comparisons were made of pupil response changes and the variables of oral contraceptive use, age, plasma glucose value, days before menses, and the time after eating. Suggestions are given for improvements in the experimental method. The significant correlations of pupil response changes with the rate of plasma glucose decline are in agreement with other reports of significant correlations between verbal ratings of hunger and satiety and capillary-venous differences in blood glucose. With some modifications in techniques, it is suggested that further studies of human satiety and hunger involve pupillometry. / Graduation date: 1978

Until recently psychologists taught that it was impossible to condition the autonomic nervous system and the smooth muscles and glands it controls by any other means than by Pavlovian techniques. In 1960, Kimmel and Hill demonstrated the possibility of instrumental conditioning of the galvanic skin response. Since then, there have been reports of learned control of a wide range of autonomic responses. In the present study, it was hypothesized that pupillary size with it's bi-directional autonomic innervation would be an excellent candidate for illustration of the same rules of conditioning by biofeedback training as has been demonstrated by other autonomic nervous system functions. A total of 10 subjects were split into 2 groups and randomly assigned to either a dilation training group or a constriction group. As hypothesized self-control of pupil diameter via the use of external feedback was demonstrated.

Because of the recent upsurge in the investigation of physiological measures as indicators of emotional states, this project was performed on the basis of Eckhard Hess' and Michel Janisse's differing ideas concerning pupil diameter as an emotional indicator. Auditory humor, 3 pre-rated levels of jokes, was recorded and presented to 10 male and 10 female subjects while respiration, skin conductance and pupil diameter were recorded. The data were subjected to various analyses of variance. Only the main effect of time samples was found to be significant. Although this effect does not support either Hess' or Janisse's hypotheses, it does show that there was some reaction and possibly could mean that the auditory stimuli utilized were not diverse enough to produce a significant pupil reaction. The investigation did show that although physiological arousal does not reveal itself, the subjects still subjectively judged the jokes to be significantly different.

Previous studies of cognitive fatigue which have used the pupillary response have centered on long term, time-induced effects. Results have indicated that pupil diameter decreases as a function of cognitive fatigue. This study examined the effects of short term, task-induced fatigue on the pupillary response.The research design involved the use of a pre/post paradigm with an interpolated mental multiplication task designed to produce cognitive fatigue. Pupil diameter and rating scale measures were obtained, as well as a measure of the subjects' numerical aptitude. By analyzing the pre/post differences in pupil diameter over time, the use of the pupillary response for the assessment of short term, task-induced cognitive fatigue was demonstrated to be feasible.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 134-142).