Date Thesis Awarded


Access Type

Honors Thesis -- Access Restricted On-Campus Only

Degree Name

Bachelors of Arts (BA)




Paul Kieffaber

Committee Members

Lisa Szykman

Jennifer Stevens


The present research used electroencephalography (EEG) measures to examine the neural mechanisms of purchase behavior. Specifically, this study examined how affective priming influences a purchase decision when brand and price are varied. Participants were presented with Yes/No purchase decision trials for 14 different grocery products- seven national brand and seven private label products- while EEG activity was recorded. Price was increased or decreased relative to a base reference price. Prior to product onset, an emotional prime was flashed. The prime was a positive, negative, or neutral image from the International Affective Picture System (IAPS). Main behavioral results showed that fewer products were bought following a negative prime relative to positive or neutral, regardless of brand type or price. Event-related potentials (ERPs) locked to the product onset revealed very early effects of emotion (VEEEs), consisting of differential brain activity between positive/negative and neutral primes at posterior sites around 125 ms. Although the positive prime did not appear to have an overall behavioral influence, this result indicates that its emotional content was still captured at the neural level. A late positive complex (LPC), which reflects an association with positive outcome, was observed between 650-1000 ms at fronto-central sites. Main LPC results showed increased LPC activity for purchase trials following a positive prime. Overall, the results are consistent with similar research and show that buying decisions are malleable. The present research is among the first to demonstrate the effect of emotional priming on purchase behavior, and offers insight on some of the brain processes that drive purchase decisions, not all of which are manifested at the behavioral level.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

On-Campus Access Only