Is that fruit fly tripping?
Giving LSD to fruit flies sounds a little like watching “racing turtle” at a pub: Fun, but unlikely to yield any really valuable new knowledge.
However, if that’s what you think, you’d be wrong.
Dr. Charles Nichols has been studying fruit flies for the better part of two decades, learning how their small brains — a mere 100,000 neurons, compared to our 86,000,000,000 — can teach us about how ours work. After all, many features of nervous systems are “conserved” across distant animal phyla, from bugs to people and everywhere in between.
We first met Dr. Nichols in Episode #196, Psychedelics vs. Inflammation. So if he sounds familiar, you’re not imagining things — but we’re covering all-new topics here.
It’s no secret that lysergic acid diethylamide produces profound effects on the human brain, and at shockingly low dosages. (Perceptual effects can be noticed by adults in as little as the 20 microgram range.) But that doesn’t mean that it would do anything similar — or anything at all in Drosophila melanogaster (better known as “fruit flies”).
When Dr. Nichols began looking into this, as a curious graduate student, it was just based on a hunch, and having learned that some other psychoactive stimulants had triggered results in Drosophila. He was prepared to see no results.
As it turned out, “tripping flies” became a linchpin of his scientific career.
The reason that LSD’s having effects on fruit flies is worth caring about is because of what we already know about how LSD effects human brains: by interacting with serotonin receptors, one of the most prevalent receptor-types in the brain — crucial to sensory perception, mood, emotional salience, and more.
If flies can “get high” on LSD, then we know that their brain’s serotonin system is mechanistically similar to ours. Meaning that…
The humble fruit fly can make an ideal guinea pig.*
In Episode #207, Dr. Nichols guides us through decades of study, citing psychedelic studies on animals from fruit flies to elephants. Along the way, we’ll learn why artificial intelligence is still a long way from giving us a virtual fly brain, a good use for stale beer, and the importance of serendipity in charting the course for a scientific career.
* Sorry, I couldn’t resist. 😉
Episode introduction: Bugs on Drugs.
This Week In Neuroscience: General Intelligence and Visual Object Recognition.
5-Star review shoutouts.
SDS news and updates.
Guest introduction: Dr. Charles Nichols.
Interview begins: Catching fruit flies.
Conceptual framework for using fruit flies to examine the effects of psychedelics and its translational potential.
Fruit fly mutants.
Giving LSD to fruit flies.
Target serotonin receptors for psychedelics in fruit flies.
Tryptophan and serotonin deficiency.
The elephant on LSD.
LSD dosing in fruit flies.
First round of experiments by Dr. Nichols.
The ability of a fruit fly to follow moving objects in it's environment.
Metabolic rate in fruit flies.
Serotonin 2A receptors.
Serotonin 2A receptors and visual processing in the human brain.
Sensory information mediated by the thalamus.
The brain, or even the thalamus, as a possible "reality filter."
Assigning meaning to sensory input by the locus coeruleus.
Research on potential therapeutic effects of psychedelics for depression and addiction.
Where the fruit fly comes in.
Default mode network in fruit flies.
Findings over the last 20 years.
Psychedelics and aggression in fruit flies.
Learning and memory in fruit flies.
Courtship behavior in fruit flies.
Attempt to map the neuronal response of fruit flies when dosed with methamphetamine.
Might mood be a concept that scales down to fruit flies?
Optogenetics in fruit fly studies and DREADD receptors.
Dr. Nichols's next research endeavors.
Will we have a complete model of the fruit fly brain anytime in the near future?
Conveying the importance of fruit fly research.
Ruthless Listener Retention Gimmick: Correlation Between Classical Psychedelic Use and Criminality.