College of Science and Health Theses and Dissertations

Date of Award

Summer 8-23-2015

Degree Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Joseph A. Mikels, PhD

Second Advisor

Linda A. Camras, PhD

Third Advisor

Kimberly Quinn, PhD


Emotional facial expressions are potent social signals that can change people’s feeling states and shape judgments of targets that are unrelated to the expressions. Whether they originate from other individuals or advertisements in the environment, facial expressions are undoubtedly one of the most prominent emotional stimuli. Thus, there is a great need to examine how facial expressions can influence potentially consequential judgments and decisions that involve uncertain or risky prospects, as such decisions are greatly impacted by emotion.

The domains of finance and health could particularly benefit from such an examination. In the financial domain, expressions of other individuals could shape investment behavior. For instance, facial expressions may trigger emotional reactions that can focus an individual on either the unwanted consequences or benefits of a risky option. In the health domain, individuals’ evaluations of the risks and benefits associated with a medical treatment could be guided by the emotionality depicted on the face of a doctor. This second domain has particular relevance to older individuals due to their greater preference for positively over negatively valenced stimuli and the importance of effectively promoting preventative health behaviors for older adults.

Thus, two studies were conducted in order to examine the role of emotional facial expressions in judgments and decisions involving risk in the financial and health domains. The first study examined whether the posing of positive (happiness), negative (fear), and neutral facial expressions could influence participants’ affective responding and ultimately their sub-optimal risk-taking and risk-avoidant behavior in a financial investment task. In Study 1, the facial posing manipulation did not have the intended effect on participants’ changes in self-reported valence. Specifically, in the neutral-posing condition, participants reported the greatest increase in negative valence and demonstrated significantly greater sub-optimal risk aversion in comparison to the fear-posing condition. Furthermore, significant relations between participants’ facial responding and sub-optimal risk seeking behavior were discovered in the neutral posing condition. Specifically, decreased corrugator and increased zygomaticus activity in response to affectively neutral expressions in the neutral-posing condition was related to increased risk seeking. This relationship between fEMG activity and risk seeking was consistent with previously described relations between positive and negative affective and risk seeking. Thus, fEMG may be a useful tool when attempting to evaluate how individuals’ affective responses to stimuli relate to their risk seeking behavior in financial decision tasks.

The second study explored whether spontaneous facial responses to emotional facial expressions presented during an influenza vaccine commercial could change participants’ evaluations (behavioral intentions, risk perceptions, and integral feelings) regarding the flu vaccine. Importantly, this study included older and younger adults to examine whether aging-related increases in the preference for positive over negative information could lead to differential influences of positive and negative facial expressions on the above-mentioned evaluations. Manipulating the facial expressions in the commercial had a significant, albeit unpredicted effect on participants’ evaluations. Relative to those who watched the smiling doctors, older and younger adults who watched the concerned doctors felt better about the vaccine. Furthermore, older adults who watched the smiling doctors reported greater increases in worry about contracting the flu in comparison to those who watched the concerned doctors. Overall, findings of Study 2 suggest that concerned rather than happy facial expressions should accompany messages that are aimed at increasing vaccination behavior.

SLP Collection


Included in

Psychology Commons