From a change in perspective after a second chance at life to hormonal changes caused by new organs, scientists are still trying to understand what causes personality changes.
A phenomenon that has drawn increasing attention is the apparent change in personality and preferences noticed by some patients after receiving an organ through a transplant.
Case studies and personal accounts suggest changes ranging from changes in taste to new interests in musicart or even changes in emotional responses. One widely cited case involved a woman who led a predominantly vegetarian lifestyle but developed a sudden craving for fried chicken after receiving a heart transplant from a donor known for enjoying fast food.
Similar effects have been observed in bone marrow transplant recipients, with reports of individuals developing new food preferences, such as acquiring a taste for pickles or switching from white wine to red wine. In addition to diet, some patients described changes in moodin life perspective and personal interests.
According to Adam Taylor, professor and director of the Clinical Anatomy Learning Center at Lancaster University, several factors can help explain these changes. In an article published in , Taylor notes that the placebo effect may play a role, as surviving a potentially fatal disease and receive a “second chance” it can naturally change a person’s outlook and behavior. However, the expert argues that physiological explanations should not be discarded.
Donated organs are biologically active and can influence body chemistry of the receiver. The heart, in particular, releases hormones such as atrial natriuretic peptide (ANP), which affect blood pressure, fluid balance and heart rate. Variations in hormone production or sensitivity introduced by a donated organ can lead to subtle but significant changes in the functioning of the body, potentially influencing mood and behavior, says .
The heart also interacts with the brain through hormonal signaling that affects stress responses and emotional regulation. Likewise, serotonin, the hormone often associated with mood, is largely produced in the intestine, which highlights the interconnectedness of bodily systems. Replacing an organ may therefore have cascading effects throughout the body.
Initial studies suggest that these experiences are far from rare. Taylor notes that up to 90% of transplant recipients report noticing some degree of personality change, although the extent and causes vary greatly. The researchers warn that more systematic studies are needed to distinguish between physiological effects, psychological factors and coincidence.
