Biopsychology Lab: COMT Genotype Associations with Vagal Tone and Frontal Alpha Asymmetry

Brittany L. Smith, Jenna E. Dunham, Brianna M. Sweeney, Chloe Dearing, Rachel H. Shepherd, Mark E. Bardgett

https://doi.org/10.59390/SMML6995

Course-based undergraduate research experiences (CUREs) engage students in the research process to promote active learning of complex material. We created a 5-week Biopsychology Laboratory (Biopsych) CURE that integrates concepts in genetics, neurotransmission, autonomic regulation, executive function, electro-encephalography, and human subjects research. The underlying principles of the Biopsych CURE focus on how the prefrontal cortex orchestrates cognitive control and coordinates parasympathetic activity. The rs4680 single nucleotide polymorphism (SNP) in the catechol-O-methyltransferase (COMT) gene may explain individual variability in prefrontal cortical function since the presence of the A versus G alleles directly affects neurotransmission in this region. To assess this, students in the Biopsych CURE conducted a prospective cohort study on themselves to examine whether there would be differences between rs4680 GG, AG, and AA genotypes in executive function, parasympathetic activity, and frontal alpha asymmetry (FAA). During the allotted class time, students successfully learned to collect buccal swab samples, isolate DNA, quantify DNA with a spectrophotometer, and use the iWorx data acquisition system to measure heart rate, vagal tone, and alpha and beta EEG waves. They also learned to analyze the data and wrote a research report on their findings. For their class research project, they found that the GG genotype had higher vagal tone compared to A carriers while taking the Stroop test, indicating greater parasympathetic activity. The GG genotype also showed higher FAA compared to A carriers while viewing emotional face presentations, indicating greater left cortical activity. This suggests that the GG genotype may display parasympathetic and cortical activity patterns that are generally conceded as advantageous to mental health. Students learned to graphically depict their data and wrote a research report on their findings. Overall, the Biopsych CURE enabled students to work actively with core topics in the field while conducting meaningful research and the course evaluations demonstrated high student satisfaction with CURE activities.