Bhavanga (Pali, "ground of becoming") is the most fundamental aspect of mind in Theravada Buddhism. It is an exclusively Theravada doctrine that differs from Sarvastivadin and Sautrantika theories of mind, and has been compared to the Mahayana concept of store-consciousness. The term does not occur in the Nikayas, though the Theravada tradition identifies it with one that does; the phenomenon described as "luminous mind." The Theravada tradition asserts that it is the bhavanga that motivates one to seek nibbana. It is first found in the Patthana, part of the Theravada Abhidhamma Pitaka.
The bhavanga concept does not directly address certain questions first raised in the Kathavatthu. The limits of Abhidharmic analysis were first raised there, then more specifically by the Sautrantikas, and then finally explicitly and systematically by the Yogacharins.
In the Theravadin Abhidhamma, both conceptualizing and mental consciousness normally arise conditioned by other mental states. However, they also have an unspecified kind of rūpa (matter, form) as "support condition" and "basis." Peter Harvey finds that incorporating this physical basis more fully may answer certain questions that the Abhidhamma does not address.
In modern times, Theravadins such as Nyanatiloka Thera have departed from traditional descriptions of the bhavanga, broadening the scope of the concept. Nyanatiloka Thera suggests that the bhavanga can be used to explain continuity of the personality in a lifetime, but that the nervous system could also be the register in which sense impressions are stored.