New data, new findings, new preprint! 🧵 Here are the results from the first psychedelic simultaneous PET-MRI study mapping LSD's receptor binding, blood flow changes, and functional connectivity. https://t.co/LHo6NSFsAy

https://t.co/PWm7azhAK5 First Australian psychedelic clinical trial shows great safety and potential for efficacy in methamphetamine use disorder! Big congrats to this team, I'm sure it was a mammoth of work :) @lizjknock

I'm defending my PhD thesis next Friday (5th Sep). It's a public event and also online, so anyone is welcome to join :) I'll do a 40 min summary of my thesis then there'll questions from the great and powerful @ProfDavidNutt and @neurovidaurre

Another great example of someone actually testing a "thing people say" about psychedelics.

Table for completeness

Has anyone made an updated version of the Glennon 1984 human dose vs 5-ht2(a) receptor Ki graph?

Our psilocybin / ketanserin blood flow paper also just hit the press :)

This is your brain on LSD🌠

Oh, I forgot to add earlier, but the occupancy fit was much better with bw-adjusted doses than fixed doses - so bodyweight is probably pretty important

6/ But now the interesting fMRI result, the decreases in GCOR correlated well with 5-HT2AR occupancy (as expected) but negatively with CBF changes, indicating effects on neurovascular coupling, which may be a serious issue for all BOLD fMRI studies to date!

5/ The study wasn't really set up for BOLD fMRI effects, but just looking at effect sizes, we see some similarities to previous work, including increased sample entropy, but also widespread decreases in global connectivity.

4/ We observed clear hysteresis between plasma LSD and subjective effects - peak experiences occurred ~30 min after peak plasma levels. This delay may relate to LSD's unique slow dissociation kinetics from 5-HT2A receptors. We don't see the same loop at all for psilocybin!

3/ Surprising vascular effects: LSD increased cerebral blood flow by ~20% and internal carotid artery flow by 28%, and didn't affect ICA diameter - the complete opposite of psilocybin, which reduces CBF and constricts the ICA. What's up with that?

2/ Key finding: LSD shows extremely high affinity for serotonin 2A receptors - IC50 of 1.93 nM with near-complete occupancy (97%) at clinical doses. We also showed maximal occupancy from only 75 mcg, indicating any differences in effect above this are due to off-target effects.

1/ Study design: We did simultaneous PET-MR scans at baseline and following a single dose of LSD between 25 and 200 mcg; two participants also got late scans once the acute drug effects had subsided.

The paper is out :) https://t.co/rh9QGHCFoq

We've launched our study of psilocybin microdosing, with 5 in-lab dosing sessions in Baltimore Our main goal is to identify a safe dose for future home dosing clinical studies. The link below has more info and the online screener https://t.co/jqVIVVGNbU

Excited to share our work "On reconstruction of cortical functional maps using subject-specific geometric and connectome eigenmodes" with the amazing people @Sina_Mansour_L @jchrispang @AndrewZalesky @dvdevill @aitchbi:

How can 2C-B 💊contribute to psychedelic neuroscience, an otherwise "forgotten" psychedelic? We went off with @singletonion ,@NL_Mason , @sattertt and Jan to take an initial look at this using 7T resting state fMRI. 👇 https://t.co/WUAYws7id4

Check out this cool investigation of the effects of sleep and sleep deprivation on brain fluid dynamics!