MDMA modulates human sensorimotor cortical pathways during gentle touch.
Imaging neuroscience (Cambridge, Mass.) January 1, 2024 Hanna Molla, Giovanni Novembre, Anya Bershad et al.
MDMA increases the perceived pleasantness of touch, but the neural mechanisms are not well understood. In a double-blind, randomized, within-subject fMRI study with 18 healthy participants, MDMA (1.5 mg/kg) compared to placebo enhanced affective ratings of gentle touch at both a slower, more pleasant speed (3 cm/s) and a faster, less pleasant speed (30 cm/s). Plasma oxytocin levels also increased more during the MDMA session. On the neural level, primary sensorimotor areas showed greater hemodynamic changes during MDMA for both touch speeds, indicating an early influence within somatosensory pathways. Changes in oxytocin levels interacted with the drug in area MT+, associated with motion perception. However, the posterior insula did not show preferential activation for the slower stroking speed.