BRAINS Cross-Cohort Symposia occur in the years between Fellows Symposia. They are offered to BRAINS Fellows, and now also Affiliates, from all prior cohorts. Topics are selected to be relevant regardless of career stage and career path. The program is designed to deepen and expand participants' professional networks, build cross-cohort community connections, develop new career skills, and address current career challenges and questions.

A pilot Cross-Cohort Symposium for Fellows was held in June 2016 outside of Seattle, WA. It featured using the Myers-Briggs Type Indicator (MBTI) as a framework to better understand personal leadership styles and the styles of others with whom Fellows work and manage.

The 2018 Cross-Cohort Symposium for Fellows took place in September 2018 in Seattle, WA. The theme was “Being an Effective Leader.” Attendees explored how to improve their ability to be an influential and effective leader in interpersonal and organizational situations. They also examined how social identities impact leadership experiences.

Due to the coronavirus pandemic, the 2020 Cross-Cohort Symposium took place virtually over four days. The virtual platform allowed BRAINS to pilot the inclusion of Affiliates as well as Fellows. The theme was "Navigating Change" and included topics such as mental health and wellness, and communicating and delivering effective talks.