When someone first walks into the average supermarket, they are greeted with mounds of produce. They find themselves asking questions like, “Why is this tomato more expensive than this one?” One of the few companies that utilize a creative marketing method is Trader Joe’s. Trader Joe’s restricts the variations of one particular item so that there are not many unnecessarily difficult choices for the shopper. The decrease in the number of choices has been shown to increase customer satisfaction in their purchases by alleviating stress, making customers lifelong friends of Trader Joe’s.¹ For everyone, making decisions can be challenging due to the overwhelming amount of choices or time pressure. But the difficulty of decision-making is not only influenced by the combination of these external factors, it may also be affected by a person’s current mental state.

The study on Trader Joe’s launched an interesting discussion over differing methods to entice consumers after finding that too many choices lead to decision paralysis and less sales. Recently, a new study has built upon previous behavioral models by adding an additional biological perspective behind decision-making. Most notably, a recent study on consumer decision-making investigates the role of serotonin on choice deferral; the choice to not make a choice; and the compromise effect, the tendency for consumers to pick the most intermediate options. 

Serotonin is a neurotransmitter that is a regulator of mood, behavior, and memory and is commonly synonymous with the feeling of euphoria. Reports find that positive mood states tend to reflect favorably on advertisements and consumer goods. It has long been known that mood affects decision-making, particularly that excess stress makes it difficult to make what would be considered normal decisions by inhibiting working memory and memory recall functions.² Because decision-making is primarily influenced by prior knowledge and memory, impairing these functions could result in detrimental side effects on one’s ability to make grounded decisions. Other findings have also concluded that stress can affect serotonin transmission in the brain, leading to fluctuations in mood and temperament.³ Aside from prior research that broadly characterizes serotonin’s role in the improvement or impairment of cognitive abilities, there have yet to be concrete studies on the impact that serotonin may have on consumer decision-making. 

A recent study by Dr. Marcel Lichters and his colleagues found a new correlation between serotonin and decision-making: decision deferral and increasing the compromise effect.⁴ In their study, they were able to manipulate serotonin levels using acute tryptophan depletion (ATD). By lowering tryptophan, a precursor to serotonin, serotonin levels in the brain are subsequently reduced.⁴ Lowering serotonin levels through this method allows researchers to specifically isolate and manipulate one neurotransmitter without impacting other functionalities. In doing so, they were able to temporarily impair cognition through artificially mimicking a serotonin deficit that may occur in consumers in a lower mood state. In the study, participants were asked to choose their purchases based on price and quality. The researchers noted how often participants hesitated, switched between items, or refused to purchase goods. The results suggest that reduced serotonin levels increase decision deferral, meaning consumers make the conscious choice to not make a decision between options. Interestingly, reduced serotonin levels also increases the compromise effect, suggesting that reduced serotonin levels may also increase the probability that the consumer will pick the intermediate option of the choices. 

For companies aiming to create a more consumer-friendly environment, increasing serotonin levels to boost the mood of their customers can significantly enhance sales. Possible ways to increase serotonin levels in consumers is to display goods around natural sunlight and other proven environmental factors from previous behavioral studies that can induce serotonin secretion.⁴ Aside from benefiting corporations, researching the biological basis of decision-making may allow for a more comprehensive understanding of the way people make potentially life-altering decisions on a daily basis.

References

1. Porcelli, A. J., & Delgado, M. R. (2017). Stress and Decision Making: Effects on Valuation, Learning, and Risk-taking. Current Opinion in Behavioral Sciences, 14, 33–39. https://doi.org/10.1016/j.cobeha.2016.11.015
2. Sarmiento, L. F., Lopes da Cunha, P., Tabares, S., Tafet, G., & Gouveia Jr, A. (2024). Decision-making under stress: A psychological and neurobiological integrative model. Brain, Behavior, & Immunity – Health, 38, 100766. https://doi.org/10.1016/j.bbih.2024.100766
3. Natarajan, R., Northrop, N. A., & Yamamoto, B. K. (2015). Protracted effects of chronic stress on serotonin dependent thermoregulation. Stress (Amsterdam, Netherlands), 18(6), 668–676. https://doi.org/10.3109/10253890.2015.1087502
4. Lichters, M., Brunnlieb, C., Nave, G., Sarstedt, M., & Vogt, B. (2016). The Influence of Serotonin Deficiency on Choice Deferral and the Compromise Effect. Journal of Marketing Research, 53(2), 183–198. https://doi.org/10.1509/jmr.14.0482

Image References

Banner Image: Understanding and Eliminating Key CX Friction Points Effectively.(2019). [Graphic].https://contentsquare.com/blog/how-to-use-customer-journey-analytics-to-eliminate-friction-for-users/