President Samhat participating in psychology studies

Senior Theses: 2006-2007

Honors Thesis:The effect of extrinsic rewards on intrinsic motivation
an honors thesis by Leandra Parris
Faculty advisor: Alliston Reid, Ph.D.

Chapter 1 of this honors thesis reviews the empirical and theoretical research on the effects of extrinsic rewards on intrinsic motivation. A wide variety of theories are identified and explained. There are two problems with previous research: the use of self reports and the inability to apply the theories to nonhumans. Response deprivation theory provides a way of integrating this research across species. Concurrent chain schedules are presented as possible alternatives to the use of self reports for measuring intrinsic motivation. Chapter 2 presents four experiments designed to test the use of concurrent chain schedules as measures of intrinsic motivation. A concurrent chain schedule using two computer games tested the effects of extrinsic rewards on intrinsic motivation. The rewards utilized were verbal praise, unexpected money, expected money for participation, and expected money for performance. This technique shows great promise for research in this field, but will require more research to optimize its effectiveness.

 Senior Theses:
A successive-approximations approach to producing complex phonemes
Rachel Hyatt, Mary Catherine McClain, Megan Propst, and Kelsey Roth
Faculty Advisor: Alliston Reid, Ph.D.

The present study utilized a multiple-modality successive-approximations method to train English-speaking participants to produce the Spanish alveolar trill /rr/. The successive-approximations approach has shown to be a useful method of shaping desired behaviors. This approach requires a target behavior to be broken down into a series of steps in which participants must complete one step accurately before progressing to the next step. Experimenters implemented a series of approximations, such as relaxation exercises, auditory and visual modeling, and motor feedback exercises while providing feedback on accuracy. Spectrogram analysis provided a comparison of the baseline and final trills of each subject, confirming that this successive-approximations approach is a successful method for acquiring the trill.

Working memory and aging: Examination of interference theory by manipulating item similarity
Ashley Clary and Ashley Zais
Faculty Advisor: Kara Bopp, Ph.D.

Working memory is the process of simultaneously manipulating and storing information temporarily (Baddeley, 2001). Previous research has found age-related differences in working memory (Craik & Jennings, 1992). The inhibition-reduction theory is one of many theories that account for the age-related decline of working memory. The current study examined the effect of interference by manipulating item similarity in verbal and visuospatial working memory tasks. The Bopp Repetition-Detection task was used to test working memory of younger and older adults. Participants were required to find a repeated stimulus in two separate locations on a computer screen simultaneously. Of interest was whether the two locations utilized the same set of stimuli (interference condition) or different types of stimuli (non-interference condition). As hypothesized, age differences were significantly reduced on non-interference trials compared to interference trials in the verbal domain. However, age differences remained consistent across conditions for the visuospatial domain. The results provide task-specific support for the inhibition theory, but also suggest the inhibition theory is not able to explain the entire age-related difference in working memory. 

Effects of expectancy and self-awareness on impression formation in children
Erica Cosh, Stephanie Johnson, and Jessica Manning
Faculty Advisor: Cecile McAninch, Ph.D.

This study, stemming from an interest in the negative outcomes of rejected children, focused on expectancy and impression formation in children.  Though there were not enough subjects recruited to see significant differences, the manipulations of positive and negative expectancies and subject self-awareness did show tendencies toward the study’s hypotheses.  Impressions formed did match the anticipated affect from given expectancies and self-awareness did have a short term effect on increasing positive ratings of a peer child with a negative expectancy.

Differences in Taste Sensitivity to Linoleic Acid between Male and Female Rats
Cameron Corbin, Rebecca Dover, Brittany Lewis, Kimberly Smith
Faculty Advisor: David Pittman, Ph.D.

Obesity is an increasingly serious health problem in the United States, as it is responsible for serious health problems and death.  Obesity is linked to ingestion of dietary fats, therefore the identification of a component of dietary fats that may increase ingestion by orosensory stimulation represents a critically important step towards controlling fat intake.  Fat is composed of a combination of several different free fatty acids, which have been shown to be detectable by rats using conditioned taste aversion methodology.  Linoleic acid appears to be more detectable than oleic acid, both of which have been  shown to increase the licking to sweet solutions, presumably by increasing the perceived sweetness of the solutions. The goal of our research is to discover if varied levels of linoleic acid increases the palatability of sucrose, a desirable tastant, in a dose-dependant manner and whether there is a difference in sensitivity for male and female rats.  Neither male nor females showed increased ingestion as the levels of linoleic acid increased, although both males and females did show an increase in licks to increasing concentrations of sucrose, as was expected.  No differences between sexes were found for linoleic acid, but a sex difference was found for sucrose concentrations.  Microstructure analysis showed that there are increases in the number of bursts with increasing concentrations of linoleic acid, and that the number of licks are regulated by the palatability of the solution rather than satiety.  Although the experiment did not reveal a sex difference for taste sensitivity to linoleic acid paired with sucrose, it did show that females have an increased sensitivity to linoleic acid alone, which can be explored through future research.

The Relationship of Worry to the Experience of Pain
Carla Turner and Tanya Frantz
Faculty Advisor: John Lefebvre, Ph.D.

Worry and general anxiety have become a common problem in the fast pace environment of today.  Low levels of worry can be positive and help people to accomplish things; however, high levels of worry can lead to anxiety and depression that can impair the completion of everyday activities. The purpose of this study was to examine the correlation between catastrophic worriers and pain. Catastrophic worriers spend an extended amount of time consumed in their worries until they reach the point of the worst impact of worry. This study investigated whether individuals with high catastrophizing tendencies perceive pain at greater intensities than individuals without catastrophizing tendencies.  Study 1 was a correlational study based on an online survey. This survey was completed by 306 people. The measures used in this survey included VNS, MPQ-SF, CATS, PCS, PASS, RRS, FPQ-III, and PANAS. Study 2 was a pilot study conducted at Wofford College. The participants were composed of 21 undergraduate students at Wofford College. The meaures that were administered included CATS, PANAS, and PCS. The participants were randomly assigned to three conditions including pain, current worry, or squirrel. A catastrophizing interview was administered. The subjects were then exposed to finger pressure pain in the Forgionne-Barber device. The participants’ pain ratings were recorded for each weight trial. The hypothesis was that as the number of catastrophizing steps increased, the pain ratings would also increase. This hypothesis was not supported by our data. The second hypothesis was that as catastrophic worry and catastrophizing increased the pain ratings would also increase. This was supported by our results.