How we interact with others and understand their emotions, intentions, and actions in a social setting is a fundamental characteristic of our human existence. The ability to integrate and understand these social experiences in a healthy manner is known as “social cognition” and “allows us to sustain interactions, develop relations with others, understand each other, and act together.”

However, a central theme underlying many psychiatric disorders is that of dysfunctional social cognition, which critically impacts the evolution and treatment of these disorders (e.g. schizophrenia, borderline personality disorder, depression, and social anxiety disorder). Despite the importance of understanding the neurobiological basis of social cognition to develop new psychiatric treatment approaches, few studies have been carried out to this end.

To remedy this paucity of research, a team of Swiss neurobiologists have conducted a study (published in the journal PNAS, in April 2016) on how psilocybin intake and consequent stimulation of serotonin receptors affected the emotional processing of study participants to negative social interactions. The authors note: “Impairments in social cognition are leading causes of disability and compromise real-world functioning, including independent living and productivity at work.” They go on to state: “[A] better understanding of the neurobiological foundations of social cognition is urgently required for the development of novel and targeted therapies.”

The researchers opted to use psilocybin, the primary hallucinogenic component found in magic mushrooms, because it binds with high affinity to several serotonin receptors in the brain. Research on the system of serotonin receptors has revealed that these receptors play a key role in the regulation of mood, emotions, learning, and memory, and are implicated in social cognition. Furthermore, psilocybin has been shown to modulate neural activity in brain areas associated with social cognition.

The Swiss research team studied the effect of psilocybin versus placebo on the processing of feelings of social exclusion/rejection by using a combination of brain imaging technologies on a set of 21 healthy volunteers who played an online ball-tossing game called Cyberball while receiving MRI scans. Cyberball was developed specifically to study in a controlled manner the effects of interpersonal ostracism and acceptance, whereby participants think they are playing with two or three other players, except that the number of times a person receives the ball and other variables are controlled by the programmer and not the participants. The game allows for the assessment of how participants react to being left out.

After conducting their experiments, the researchers observed that psilocybin administration and its consequent effects on the serotonin receptor system led to significantly reduced activation of key brain areas involved in the processing of social exclusion. In other words, participants receiving the psilocybin treatment were less affected by feeling left out of the Cyberball game when the other “players” were essentially playing keep-away. This is in contrast to the participants receiving the placebo, who exhibited increased activation in those brain regions associated with social exclusion processing.

Furthermore, the researchers found a positive correlation between activity in a key area of the brain involved in social exclusion processing, called the midcingulate cortex, and the subjective experiences of the self in the participants who received the psilocybin. What this means is that as the midcingulate cortex was activated by psilocybin, participants felt an increased sense of being connected or at one with everything.

The authors explain: “[The] correlation between experience of unity and social pain processing may indicate that alterations in the sense of self after Psilocybin administration are import for changes in social interaction processing… which suggests that the sense of self can profoundly impact the experience of interpersonal relationships.”

They go onto to talk about how this feeling of being connected, brought on by psilocybin, “may also lead to an increased connection between oneself and other human beings, as well as stronger identification and empathic encounters with others,” which will consequently allow “negative experiences [to be] more bearable.” It follows that this increased connection and empathy could carry over favorably into therapeutic scenarios, supporting the relationship between client and therapist, allowing for the discussion of “painful experiences in a protective and secure environment.”

Interestingly, in a similar study conducted on MDMA and social exclusion, researchers discovered that MDMA also reduced the effect of social exclusion on mood and self-esteem. However, administration of MDMA affected perception of social exclusion because the participants tended to overestimate the number of times they received a throw. This is in stark contrast to psilocybin, where all participants retained an uncompromised awareness of how many times they received the ball; consequently, they were well aware of being socially excluded. The authors conclude: “Whereas MDMA seems to affect the perception of social exclusion, psilocybin may actually reduce the experience of social pain itself without significantly influencing the awareness of being excluded.”

Understanding the neurobiological basis of the processing of social pain and rejection experiences will ultimately lead to improved psychiatric treatment options for people who suffer from disorders influenced by social factors. The Swiss researchers have shown that psilocybin administration significantly lessened social pain processing by modulating neuronal activity in key areas of the brain linked to social cognition, but caution that their findings were based on a pool of healthy volunteers. Thus, they may not “translate directly” to actual psychiatric patients suffering from severe social exclusion experiences (e.g. schizophrenia patients).

Regardless, psilocybin is proving itself to be a remarkable asset to the human experience at multiple levels (social, emotional, and spiritual) and will be an instrumental tool in increasing our knowledge about social and emotional processes at the neurobiological level, especially those underlying psychiatric disorders.