Psychology ETDs

Publication Date

Spring 5-16-2026

Abstract

Short-form video platforms like TikTok have quickly become the fastest growing segment of social media, thanks to powerful algorithms serving up personalized content driven by large quantities of user data. This study investigates the neuropsychological correlates of digital media use, with a particular focus on TikTok and smartphone screen time among young adults. Combining correlational analyses and an experimental design (n = 49; n = 44 included in final sample), we examined the relationship between digital media use and cognitive and emotional functioning across multiple domains. Objective measures of digital media consumption (daily average screen time and time on TikTok) were collected alongside popular subjective assessments of “problematic” use (the Internet Addiction Test and Bergen Social Media Scale). Participants were found to spend an average of over two hours daily on the platform, compared to existing average estimates of 53 minutes per day for U.S. users. In the correlational arm of the study, participants completed standardized neuropsychological evaluations using the NIH Toolbox and a series of validated questionnaires. Findings revealed distinct cognitive relationships for different measures of digital media use. Looking at various domains of cognitive functioning, significant negative associations were found between daily average screen time and working memory performance. Subjective measures of problematic use were more strongly associated with deficits in episodic memory. Problematic social media use also correlated with indicators of psychological distress, including anxiety, depression, and stress. In the experimental arm of the study, participants also performed a motivated decision-making task in each of two conditions: following 1) a 10-minute exposure to their TikTok feed, or 2) exposure to 10 minutes of a random TikTok feed. This personalized feed manipulation occurred within-subjects across two study visits. The experiment yielded complex three-way interactions between exposure to personalized content, prior TikTok use, and decision-making behavior. This study bridges gaps in our understanding of how to research novel digital media and what areas of cognition might be affected.

Degree Name

Psychology

Level of Degree

Masters

Department Name

Psychology

First Committee Member (Chair)

Jeremy Hogeveen

Second Committee Member

Benjamin Clark

Third Committee Member

Joshua Grubbs

Language

English

Keywords

TikTok, Social Media, Neuropsychology, Screen time, Episodic Memory, Social Media Addiction

Document Type

Thesis

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