Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
May 25, 2026
Sheida Shadani, Kaspar McCoy, Lina Ong et al.
A single dose of psilocybin (1.5 mg/kg) in C57BL/6 J mice produces sex-specific effects on social behavior and dopamine signaling. In females, psilocybin acutely increased huddling and induced hypothermia, and post-acutely enhanced novelty-seeking and grooming, with no comparable effects in males. By 24 hours, males showed reduced grooming and rearing but increased sociability toward a cage-mate, accompanied by blunted novelty-evoked nucleus accumbens dopamine responses lasting up to 7 days. At 7 days, females shifted social preference toward familiarity, associated with prolonged dopamine release during familiar interactions, while males increased grooming. Both 5-HT1A and 5-HT2A receptors contributed to these sex-specific behavioral effects.
Psychedelics.
February 3, 2026
Sheida Shadani, Erika Greaves, Zane B. Andrews et al.
Psilocybin did not alter sociability in female mice under metabolic stressors—activity-based anorexia, food restriction, or running wheels—but increased preference for social familiarity (reduced novelty-seeking) in control mice. Both activity-based anorexia and running wheel groups showed elevated novelty-seeking behavior, though with distinct social patterns. Psilocybin raised levels of the proinflammatory cytokine interleukin-6 (IL-6) in running wheel mice, and that increase correlated with preference for novelty; no such relationship appeared in the other groups. These context-dependent effects on social behavior and inflammation highlight the need for further research on psilocybin's mechanisms across sexes and disease models.
bioRxiv (Cold Spring Harbor Laboratory)
December 22, 2025
Sheida Shadani, Kaspar McCoy, Lina Ong et al.
A single dose of psilocybin (1.5 mg/kg) alters social behaviors in C57BL/6J mice in sex-specific ways. In females, psilocybin acutely triggers huddling linked to body temperature changes, enhances preference for social novelty 4 hours after administration lasting about 24 hours, but reverses to a preference for familiar over novel conspecifics 7 days later, associated with prolonged nucleus accumbens dopamine signaling during familiar sniffing. In males, psilocybin reduces stress-related behaviors at 24 hours and increases preference for familiar conspecifics, with blunted novelty-evoked dopamine responses at both 24 hours and 7 days. Both 5-HT1A and 5-HT2A receptors modulate these behaviors in sex-specific ways. The prosocial effects of psychedelics are not universal, emphasizing the need for sex-informed approaches.
bioRxiv (Cold Spring Harbor Laboratory)
October 15, 2025
Sheida Shadani, Erika Greaves, Zane B. Andrews et al.
preprint
A single dose of psilocybin did not alter sociability in female mice exposed to activity-based anorexia, food restriction, or exercise, but increased preference for familiarity in control mice. Novelty-seeking behavior rose in both anorexia-model and exercise mice, with distinct social patterns. Psilocybin elevated the inflammatory marker interleukin-6 in exercised mice, which correlated with novelty preference; no such link appeared in other groups. These context-dependent effects on social behavior and inflammation underscore the need to study psilocybin's mechanisms across sexes and disease models.