A few studies have uncovered what may “show” aspects of the donor in those who receive the transplanted organ.

Organ transplants are believed to be the process of implanting an organ from a donor into a new recipient — nothing more. However, several studies focus on the unsettling beliefs or behaviors that recipients reveal relative to the donors. No, it’s not something from Mary Shelley’s writings or Tim Burton’s films, and it is both intriguing and curious, perhaps frightening, at the same time.

The belief has always been that memory resides in the brain, yet we know there may be other types of memory reservoirs that don’t remain in the brain but may be in other areas of our bodies, organs, or anywhere. Just because we haven’t discovered all of them doesn’t mean they don’t exist.

We are now in an era of discovery, probably unlike any other area aside from the time when Leonardo da Vinci was doing dissections and anatomic drawings in his studio. New observations are pushing us into these areas of the unknown; some are stunning, and one area is heart transplants.

Overall, these findings support the idea that heart transplant patients experience “exosome memory transfer.” There is evidence to support the idea that at least some of our memories are stored in the heart and move around in the blood pathways over time. This idea simplifies at least some parts of how the heart works when remembering things. Memories are mostly made in the brain, but it’s not the only place.

Exosomes move memory from the cells to the heart and back again. This changes all the time, throughout a person’s life. The nerve paths do not play a role at all or very little. Still, this does not mean that memories do not also form in the heart. This idea is not completely ruled out, either. Exosome memory transfer could be one reason people with heart transplants change who they are.

In 2020, just under 8200 heart transplants were done worldwide; in 2021, more than 144,000 organs were transferred. Transplantation surgery can have big effects on a person’s mental health, and some patients worry that they will take on the personality traits of their donor.

Studies examining heart donation recipients have found that their personalities change after getting a new organ. Some of them even started to exhibit traits that were present in their donors. Reports like this have been found in both medical and non-medical journals. Did they receive information on their donors and unconsciously incorporate some traits, and believe it was because the heart carried these traits with it?

A study in Canada looked at 27 teenage heart transplant recipients and found that many of them had trouble integrating their ideas of “self” and “other” (i.e., their donated organ). Some of them also had thoughts or questions about possibly taking on the traits of their donor through their donor’s heart. However, no numbers were given for how often mental changes happen.

People who received kidney, liver, or other organs also said their emotions, sense of smell, and food preferences changed after the transplant. However, these changes were generally temporary and not as strong as the changes seen in people who received hearts

Reports of mental changes and memories of past events are not now just showing up. One woman who had a heart and lung transplant said that after her surgery, she noticed changes in her habits, views, and tastes. She had strange cravings for foods she used to hate. For example, she was a dancer and director who cared about her health, but as soon as she got out of the hospital, she had to go to Kentucky Fried Chicken and order chicken nuggets, which she never did.

Now, it made her feel better to wear cool colors instead of the bright reds and oranges she used to like. Then she started acting in a way that was not like her at all — it was more like the donor’s attitude. In a strange twist, Kentucky Fried Chicken nuggets that had not been eaten were found in the jacket of the young male giver who had been killed.

Anyone interested in reading more on the subject might want to read “The Heart’s Code,” which details findings related to heart transplants and changes recipients have experienced.

Some patients are afraid that their personalities might change after receiving an organ transplant. Recommendations are that this is something that should be talked about with potential transplant recipients before they go through with the surgery, as it might make them less hesitant and more likely to follow through with their post-transplant treatment. Heart transplant recipients (91.3%) and other organ transplant patients (87.5% of participants) said they had changed somehow. These results show that personality changes are common after any organ donation, though this may again be due to selection bias.

As the results of many studies over the past 50 years have indicated, there is more memories stories in places we never considered. Stored memories may reside in organs used for transplant and may result in recipients experiencing changes no one had ever expected.