Date of Graduation


Document Type


Degree Type



Eberly College of Arts and Sciences



Committee Chair

Kevin Larkin

Committee Co-Chair

Julie Brefczynski-Lewis

Committee Member

Barry Edelstein

Committee Member

Amy Gentzler

Committee Member

Julie Hicks-Patrick


Positive emotions are related to improved physical and mental health. One potential mechanism through which positive emotions affect physical health is by reducing cardiovascular reactivity to stress and enhancing recovery from stress. The undoing hypothesis proposes physiological recovery from stressful events can be improved by induction of positive emotions. Although there is some research supporting the undoing hypothesis, the evidence is largely mixed. The purpose of the present study was to compare two methods of inducing positive emotions to determine if one method was superior at inducing positive emotions and thereby determine how each method affected cardiovascular recovery from stress among a sample of undergraduate students. The study employed a 2 x 2 between-subjects design. The first between subjects factor, Smile, involved a manipulation based on the facial feedback hypothesis (Smile, No-smile). The second between subjects factor, Event, involved exposure to photographs of a pleasant or neutral event (Happy, Neutral). Participants completed a mental arithmetic stressor task while engaging in the positive emotion induction tasks. Measures of cardiovascular responses were obtained and areas under the curve were calculated for each cardiovascular measure during a recovery period following exposure to stress.;Results demonstrated that the smile manipulation was associated with increased diastolic blood pressure responses to stress and that exposure to personally relevant photographs of pleasant events was associated with increased systolic blood pressure responses to stress. No significant effects of positive emotions were observed on measures of cardiovascular recovery from stress.;The findings observed in the current study did not support the undoing hypothesis. There are several possible explanations for the inconsistent findings. The types of positive emotion induction tasks used in the present study differed from previous research, which may account for the differences in findings. Further, recovery in the present study was measured by area under the curve. This method has not previously been used to examine recovery with the undoing hypothesis. Future research should continue to examine the undoing hypothesis to uncover reasons for the lack of consistent findings across studies that have employed various methods of measuring recovery.