We discovered two main associations between PAU-PRS and brain morphometry. First, PAU-PRS were associated with lower frontal pole volume; this finding aligns with evidence that adolescents who drink heavily have lower volume here (32). Unlike past studies showing reduced volume is associated with increased impulsive behaviors (33), we found no evidence that a proxy behavior of externalizing psychopathology is associated with frontal pole volume. This may be because of differences in measurement between trait impulsivity and trait externalizing.
