It is true: there is a newly-discovered set of neurons found in a type of worm that, when activated, causes the male of the species to forego food in search of sex. That this set of neurons was just discovered actually does matter to the lives of humans. Or at least, it could. But not because it confirms the cliche of men starving for sex:

Researchers may have figured out why men can prioritize sex over food. Well, some men.

It’s a matter of two “mystery” neurons, suggest researchers at University College London.

They found that these extra neurons — which are unique to males — allow them to remember and seek sex even at the expense of food and are also behind some sex-based differences in learning.

So, what happened?

C. elegans is a species of worm about which we know a surprising amount. In biology research, there are some species of plants and animals that, for one reason or another, get more attention than others. Elodia and Drosophila (fruit flies) are very common study species.

C. elegans is popular because it is a simple organism that happens to share a lot of common traits with more advanced forms of life like humans. By studying C. elegans, we can often make intelligent extrapolations about how things work in other species.

In particular, C. elegans has the distinction of being the only species of life for which we have a complete neuronal map. Every neuron, every synapse (connections between neurons), every feature of the neural network of the C. elegans has been long-since mapped and analyzed… at least, so we thought.

Two researchers at the University College of London, wife and husband team Dr. Arantza Barrios and Dr. Richard Poole, research the sexual dimorphism of C. elegans. Sexual dimorphism means that different sexes have different traits (think boobs. I know I do).

In the past, the dimorphism of C. elegans has always been studied in a different portion of the worm, where differences are more obvious: the tail. These researchers discovered one set of sexually-dimorphous neurons in the head of the animals, which they named the Mystery Neurons of the Male (MNM).

What they do turns out not to be much of a mystery at all: they learn to recognize the opposite sex as a priority stimulus. Don’t we all? When the opposite sex is near – which turn out to be hermophrodites, in the C. elegens’ case – the worm with active MNM will ignore other homeostatic functions – like eating – in favour of pursuing sexual reproduction.

So. There you have it: males of the C. elegens species will forego eating in favour of sex. Or at least, they will favour sexual reproduction over other things. Not quite the whiz-bang you were hoping for? Of course not, because non-science – and even some science – news sources want to focus on sex, sex, sex. Yet the reality of what the boffins in London discovered is way more important and honestly cooler.

Why it matters

Worms getting it on don’t seem terribly relevant to humans. And indeed, they are not. What really matters is, again, the fact that simple organisms like the C. elegens can give us clues to our own biology. In this case, science has been looking for the keys to understanding sexual dimorphism in human cognition. We know that some decision making in humans is consistently different from one sex to the other. While much of the scientific community has been certain that such a difference also existed in the brain’s wiring, science has thus far not been able to pin that difference down.

That a simple creature so far removed from us in the evolutionary tree should have such a simple device for continuing the species may indicate that a similar development across species. Or, it may not. It’s just way too early to tell.

The other, perhaps even more significant, discovery that this new development represents is the appearance of glial cells in such a simple organism. Here in Rochester, we know all about glial cells, because that’s what our neuroscientists specialize in.

Glial cells are, effectively, stem cells for the brain. They are part of the glimphatic system, and their job is to grow more neuronal  cells when old ones wear out or are damaged. Remember Nancy Reagan in the 80’s? Insisting that you could not grow brain cells back, so don’t do drugs? Well, the old bat was wrong. Do drugs: your glial cells will make more neurons, no sweat.

It’s is significant that glia create entirely new neuronal cells at different age stages, at least in the case of C. elegans. Rather than simply creating the same type of cell over and over again, it seems like glia (individual glial cells) can alter their behavior throughout the lifetime of an individual. It means glia are a lot more flexible than we knew, which may point the way towards therapies for neurodegenerative disease like Parkinson’s or Alzheimer’s.


So, maybe not the sexy news you were hoping for. If you’d been planning on filling out your 6pm news cast or your morning radio talk show? Sorry. But understanding the fundaments of human cognition and finding cures for wasting brain disease seems kind of important. But these messages got lost, because pee-pees and hoo-hahs. Maybe, if the media industry at large could stop giggling and take this more seriously, we could appreciate this amazing discovery for what it is.

But for now, dear reader, it’s just you and us.

In August of last year, we reported on the recent discovery of a “Glymphatic Pathway,” which is essentially a waste-disposal system for the brain. This system, discovered by Jeffrey Iliff and Maiken Nedergaard of the University of Rochester, mirrors the role of the lymphatic system in other organs of the body. The system removes waste proteins from the brain and the effective running of this system, scientists believe, is the difference between a healthy brain and one with Alzheimer’s Disease.

Building on that research, boffins at the University of Stony Brook used tracing elements and MRI scanning to trace the entire glymphatic system, from the back of the brain to the nasal cavity, to better understand the pathway and what a damaged one might look like:

This advanced imaging technique has the potential to be used as a way to monitor the human brain to map brain waste clearance and access (sic) disease susceptibility. Theoretically, if clinicians were able to capture a defect in the glymphatic system where certain channels are malfunctioning, plaque formation would likely accelerate, Benveniste says.

This plaque buildup may be an early sign of disease susceptibility before evidence of any cognitive changes. Though there is no known way to repair malfunctions in the glymphatic system, the research team is investigating ways to repair or open malfunctioning channels.

Mapping out this system is part of a wider effort to understand “white matter” in the neurological system.

Sometimes, there’s nothing more cathartic than taking out the garbage – even for your brain.

Neuroscientists at University of Rochester Medical Center have discovered a previously unrecognized system that drains waste from the brain. Dubbed the “glymphatic system” due to its similarities with the lymphatic system, but instead managed by brain cells known as glial cells, this new-found system brings hope for many brain conditions, including Alzheimer’s Disease, Parkinson’s Disease, stroke, and traumatic brain injuries, which are all attributed in some way to waste protein build up on the brain.

Here’s how it works – the highly organized system acts as a series of pipes, piggybacking off of the brain’s blood vessels to drain away waste products. Think of it as if the brain has two big garbage cans; the first one collecting waste through a gradual trickle, the second one under much more pressure, pushing large volumes daily to carry waste away more forcefully.

That’s a lot going on in our brains on a daily basis – so how were we unaware of all of this until now? According to scientists, the system only works when it’s intact and operating in a living brain, which had previously been extremely difficult. To study the living, whole brain, the team at U of R used a technology known as two-photon microscopy, which allows scientists to look at the flow of blood and other substances in the brain of living animals – in this case, mice.

This is not the first discovery to stem from this research at U of R.  Back in the spring, a similar study found that parts of the brain that were not cleaning properly could be to blame for ADHD.  This is all great news, though. Once a definitive  biological cause has been pinned down with certainty, then medicines can be created to treat the problem.

See? Your mom wasn’t kidding when she told you it’s important to clean!