This study extends research on Communicatively Restricted Organizational Stress (CROS) by documenting the impact of assimilation, organizational support, and impostor syndrome on CROS in a Graduate Teaching Assistant (GTA) student population. Through a survey of 102 GTAs from U.S. universities, we found that higher levels of assimilation and organizational support, along with lower levels of impostor syndrome, predicted lower CROS Prevalence. Lower CROS Prevalence then predicted lower CROS Distress. Fellow graduate student familiarity, acculturation, and recognition appeared to play a more significant role in CROS Prevalence than other dimensions of assimilation. Our findings support the implementation of targeted socialization efforts for addressing graduate student mental health; we conclude with several recommendations based on our data.