The purpose of this study was to test Beatty and McCroskey\u27s communibiological model of trait verbal aggressiveness. In general, this model views trait verbal aggressiveness as an expression of temperament; specifically, that trait verbal aggressiveness represents low thresholds for the fight or flight (FFS) neurobiological system. This model further contends that behavioral inhibition circuitry (BIS) moderates FFS activation by tempering aggressive impulses, otherwise FFS activation would manifest itself in the form of physical rather than verbal attacks. Beatty and McCroskey (1997) propose that low thresholds for stimulating the behavioral activation system (BAS) should be related to trait verbal aggressiveness to the extent that the construct involves a proactive rather than a purely reactive interpersonal function. Because previous research indicated that psychoticism (P), neuroticism (N) and extroversion (E) represent psychological manifestations of the FFS, BIS, and BAS systems, respectively, hypotheses linking P, N, and E to trait verbal aggressiveness (VAS) were tested. A multiple regression equation based on disattenuated correlations explained approximately 46% of the variance in VAS scores. Specifically, (1) the results for P and N were consistent with predictions derived from Beatty and McCroskey\u27s model, and (2) the results for E were indicative of a purely reactive function of trait verbal aggressiveness. Implications for theory and research are discussed