Imperial College London

Dr Christopher Timmermann

Faculty of MedicineDepartment of Brain Sciences

Research Fellow



+44 (0)20 7594 7994c.timmermann-slater15 CV




Burlington DanesHammersmith Campus






BibTex format

author = {Timmermann, Slater CB and Roseman, L and Haridas, S and Rosas, F and Luan, L and Kettner, H and Martell, J and Erritzoe, D and Tagliazucchi, E and Pallavicini, C and Girn, M and Alamia, A and Leech, R and Carhart-Harris, R},
doi = {10.1073/pnas.2218949120},
journal = {Proceedings of the National Academy of Sciences of USA},
pages = {1--12},
title = {Human brain effects of DMT assessed via EEG-fMRI},
url = {},
volume = {120},
year = {2023}

RIS format (EndNote, RefMan)

AB - Psychedelics have attracted medical interest, but their effects on human brain function are incompletely understood. In a comprehensive, within-subjects, placebo-controlled design, we acquired multimodal neuroimaging [i.e., EEG-fMRI (electroencephalography-functional MRI)] data to assess the effects of intravenous (IV) N,N-Dimethyltryptamine (DMT) on brain function in 20 healthy volunteers. Simultaneous EEG-fMRI was acquired prior to, during, and after a bolus IV administration of 20 mg DMT, and, separately, placebo. At dosages consistent with the present study, DMT, a serotonin 2A receptor (5-HT2AR) agonist, induces a deeply immersive and radically altered state of consciousness. DMT is thus a useful research tool for probing the neural correlates of conscious experience. Here, fMRI results revealed robust increases in global functional connectivity (GFC), network disintegration and desegregation, and a compression of the principal cortical gradient under DMT. GFC × subjective intensity maps correlated with independent positron emission tomography (PET)-derived 5-HT2AR maps, and both overlapped with meta-analytical data implying human-specific psychological functions. Changes in major EEG-measured neurophysiological properties correlated with specific changes in various fMRI metrics, enriching our understanding of the neural basis of DMT’s effects. The present findings advance on previous work by confirming a predominant action of DMT—and likely other 5-HT2AR agonist psychedelics—on the brain’s transmodal association pole, i.e., the neurodevelopmentally and evolutionarily recent cortex that is associated with species-specific psychological advancements, and high expression of 5-HT2A receptors.
AU - Timmermann,Slater CB
AU - Roseman,L
AU - Haridas,S
AU - Rosas,F
AU - Luan,L
AU - Kettner,H
AU - Martell,J
AU - Erritzoe,D
AU - Tagliazucchi,E
AU - Pallavicini,C
AU - Girn,M
AU - Alamia,A
AU - Leech,R
AU - Carhart-Harris,R
DO - 10.1073/pnas.2218949120
EP - 12
PY - 2023///
SN - 0027-8424
SP - 1
TI - Human brain effects of DMT assessed via EEG-fMRI
T2 - Proceedings of the National Academy of Sciences of USA
UR -
UR -
UR -
VL - 120
ER -