MDMA modulates human sensorimotor cortical pathways during gentle touch.
Hanna Molla, Giovanni Novembre, Anya Bershad, Linda Handlin, Irene Perini, Harriet de Wit, India Morrison
Imaging neuroscience (Cambridge, Mass.) January 1, 2024 Peer reviewed DOI: 10.1162/imag_a_00316 via PubMed
Summary
MDMA administration at 1.5 mg/kg significantly enhanced the pleasantness of touch compared to a placebo in a study involving 18 healthy participants. Participants rated touch stimulation more positively during the MDMA session, and plasma oxytocin levels increased more than during the placebo session. fMRI results showed greater hemodynamic changes in primary sensorimotor areas during MDMA exposure for both slow and fast touch speeds, indicating early influences on somatosensory pathways.
Study at a glance
| Design | double-blind, randomized, within-subject design |
|---|---|
| Sample size | 18 |
| Population | healthy participants |
| Key finding | Participants rated touch stimulation as more pleasant during MDMA administration compared to placebo. |
Abstract
The stimulant ± 3,4-methylenedioxymethamphetamine (MDMA) has been shown to enhance the perceived pleasantness of touch. However, the underlying neural processes contributing to touch-related effects of MDMA are not well understood. Using a double-blind, randomized, within-subject design, this study used fMRI to examine hemodynamic changes following MDMA (1.5 mg/kg) vs. lactose placebo administration during gentle touch stimulation in a healthy sample (N= 18). Participants were stroked on the forearm at a slower, more pleasant (3 cm/s), and a faster (30 cm/s), less pleasant speed. For the MDMA session, participants' affective ratings of touch stimulation were higher than their placebo ratings. Increase in plasma oxytocin (OT) levels was also greater during the MDMA session. On the neural level, primary sensorimotor areas showed greater hemodynamic changes during the MDMA than during the placebo session for both touch speeds, indicating a relatively early influence within somatosensory pathways. Changes in OT levels showed an interaction with drug in an occipitotemporal region, area MT+, associated with motion perception. However, posterior insula did not show preferential activation for the slower stroking speed. These initial findings provide a basis for extending our knowledge of the neural processes underlying the effect of MDMA on affective touch.