Background: As competition for medical school admission intensifies, there is greater focus on the hidden curriculum—informal lessons learned during medical training that influence patient care, burnout resilience, and professional identity. Anticipatory socialization, the preliminary adoption by students of beliefs and behaviors perceived as essential for medical school success before matriculation, plays a crucial role in this process.

Anticipatory socialization impacts medical student and resident development, but limited research exists on its impact on pre-medical students' identity formation. This early identity shapes future professional behavior. This study explores how anticipatory socialization influences pre-medical students’ professional identity formation, focusing on how this process affects volunteering. Moreover, through the framework of self-determination theory, a general motivation theory, this study examines how motivational shifts influenced by anticipatory socialization impact intrinsic motivation for volunteering among pre-medical students.

Methods: Thirteen undergraduate, self-described pre-medical students from a North American university, who recently volunteered in a pre-medical capacity, participated in a semi-structured interview (September - November 2021). Open-ended questions explored their volunteer roles and the influence of their pre-medical identity on volunteering. Interviews were audio-recorded, transcribed, and thematically analyzed using content analysis within the framework of self-determination theory. Emerging themes in volunteering motivations, mindset changes due to the pre-medical identity, and the role of volunteering in medical school admissions were grouped into typologies, refined through group discussion.

Results: Thirteen semi-structured interviews were analyzed, revealing three major themes with eight subthemes. The first theme, volunteering motivation, included subthemes on motivations and goals. The second theme, the role of volunteering, had subthemes on lessons learned, challenges, and how volunteering should be evaluated in medical school applications. The third theme, the impact of pre-medical identities on volunteering, included subthemes on the impact of pre-medical identities, volunteering intentions, and the causes of pre-medical culture. Participants described a shift from intrinsic to extrinsic motivation for volunteering, before matriculation, due to anticipatory socialization, driven by the loss of self-determination theory’s three-factor structure (autonomy, competence, and relatedness) and various external factors.

Conclusion: In this study, anticipatory socialization among pre-medical students in North America, driven by peer competition, ambiguity in the medical school admissions process, and perceived expectations, caused a shift, based on self-determination theory, from intrinsic to extrinsic motivation for volunteering before matriculation. This shift is largely perceived by students as detrimental, with a return to intrinsic motivation seen as beneficial.