Abstract  It is generally assumed that learning is restricted to neural and immune systems. However, the systemic memory hypothesis predicts that all dynamical systems that contain recurrent feedback loops store information and energy to various degrees. Sensitive transplant patients may evidence personal changes that parallel the history of their donors. The objective of this study was to evaluate whether changes following heart transplant surgery parallel the history of the donors. We conducted open-ended interviews with volunteer transplant recipients, recipient families or friends, and donor families or friends, in hospitals in various parts of the country. Patients included ten recipients who had received heart or heart–lung transplants. Main outcome measures were transcripts of audiotaped interviews quoted verbatim. Two to 5 parallels per case were observed between changes following surgery and the histories of the donors. Parallels included changes in food, music, art, sexual, recreational, and career preferences, as well as specific instances of perceptions of names and sensory experiences related to the donors. The incidence of recipient awareness of personal changes in cardiac transplant patients is unknown. The effects of the immunosuppressant drugs, stress of the surgery, and statistical coincidence are insufficient to explain the findings. We suggest that cellular memory, possibly systemic memory, is a plausible explanation for these parallels.