Social bonds play an important role in human well-being, and neuroscience is increasingly exploring how our brains respond during close interactions. One particularly interesting phenomenon is interbrain synchrony—the alignment of neural activity between two people. Researchers have now investigated whether psychedelic experiences can influence this process in couples.
How the Study Was Conducted
The study involved 25 couples who received either LSD or a placebo on separate occasions. Researchers recorded their brain activity using electroencephalography while partners completed several activities together. These included sitting quietly next to each other, holding hands, and completing a shared drawing task.
The participants also described their subjective feelings, including love, safety and emotional closeness. This allowed researchers to compare measurable changes in brain activity with the way participants experienced their relationships.
Stronger Feelings and Greater Synchrony
After taking LSD, participants reported stronger feelings of love and security, while feelings of loneliness decreased. The EEG recordings revealed an increase in synchronization within the theta frequency range when partners were simply sitting together.
Interestingly, the same effect was not observed during more active tasks. This suggests that the changes may be particularly relevant to quiet moments of shared presence rather than communication or coordinated activity.
Why the Findings Matter
The results raise intriguing questions about the relationship between psychedelic experiences and social connection. Increased neural synchrony could indicate that partners become more attuned to each other during certain states of consciousness.
However, the findings should not be interpreted as proof that psychedelics automatically improve relationships. The study was relatively small, and participants generally knew whether they had received LSD. The emotional experience of taking part in the study may also have influenced the results.
What Researchers Still Need to Understand
Future research will need to examine whether similar effects appear in larger and more diverse groups. Scientists also need to determine how long changes in neural synchrony last and whether they have any meaningful connection with long-term relationship outcomes.
The study nevertheless provides another example of how modern neuroscience can investigate interpersonal experiences that are difficult to measure. Instead of looking only at the activity of an individual brain, researchers are beginning to examine what happens when two people interact—and whether altered states of consciousness can change the way their brains respond to one another.