Joel Mainland

1/3 The humble glass jar is a workhorse in olfactory research, but comes w/ hidden problems:
- Unknown headspace concentration
- Concentration dilution by ambient air

These add noise to odor measurements.

Our preprint introduces something new, something bag.🧪 @jmainland.bsky.social & Matt Andres

High-Fidelity Tuning of Olfactory Mixture Distances in the Perceptual Space of Smell Through a Community Effort https://www.biorxiv.org/content/10.64898/2025.12.13.694160v1

Cool new post-doctoral position in my lab on the area of human social chemosignaling. What role does odor and olfaction play in shaping social behavior?

(Here also is a 10-minute video about this new line of work in the Human Nature Lab: humannaturelab.net/making-of/so... .)

Please share.

Decoding human olfaction by high heterologous expression of odorant receptors detecting signature odorants Emter et al. improve in vitro expression of odorant receptors (OR) by engineering the C-terminal domain. With a library of engineered ORs, they discover ORs for signature odorants, which they relate…

Scientists at Firmenich buff.ly/jq1TyYa and now Givaudan buff.ly/u2gP5Ow report several olfactory receptors that appear to map cleanly onto specific odor notes (earthy, grapefruit, woody, etc.). 🧪

New preprint from the very talented Bob Pellegrino! 🧪

How do our genes influence our sense of smell? Study finds sex-specific effects How we smell is not just a matter of taste—it's also influenced by our genes. An international team of researchers led by scientists from Leipzig University has conducted the largest genetic study to date on the human sense of smell.

Analysis of over 21,000 individuals identifies seven new genetic regions linked to odor perception, with some effects differing between men and women and connections to Alzheimer's risk. doi.org/g9vn4j

In May we launched the DREAM Olfactory Mixtures Prediction Challenge 2025. The leaderboard round closed yesterday and 71 teams submitted predictions! Even if you missed the leaderboard phase, you can still submit a final model for the August 8th deadline.

DREAM Olfactory Mixtures Prediction Challenge 2025 'DREAM Olfactory Mixtures Prediction Challenge 2025' (Synapse ID: syn64743570) is a project on Synapse. Synapse is a platform for supporting scientific collaborations centered around shared biomed...

My favorite part of these challenges is actually after the competition closes. All participants get together and work collaboratively on a manuscript summarizing key insights and where the field stands. Join us! www.synapse.org/Synapse:syn6...

Building on last year's Mixture Discriminability Challenge, we're offering a dataset of 650+ blends, each assessed by trained panelists using a 51-word scent lexicon.

Most existing models predict odor perception at just one concentration. Yet, some odorants dramatically shift in quality as concentration changes—such as grapefruit mercaptan, pleasantly fruity at low concentrations but distinctly sulfurous at high levels.

This year, we have two challenges: 1) Predicting how odor quality changes with concentration, and 2) Describing an olfactory mixture. You can make up to three leaderboard submissions until July 21st, with one final submission allowed before August 8th.

Last year, we ran the second DREAM Olfaction Prediction Challenge www.synapse.org/Synapse:syn5... . This time focusing on predicting the similarity of mixture pairs.

Ten years ago the first DREAM Olfaction Prediction Challenge launched to predict the smell of a molecule from its structure. This led to a publication establishing benchmarks doi.org/10.1126/scie... , and then a subsequent surge in predictive modeling.

DREAM Olfactory Mixtures Prediction Challenge 2025 'DREAM Olfactory Mixtures Prediction Challenge 2025' (Synapse ID: syn64743570) is a project on Synapse. Synapse is a platform for supporting scientific collaborations centered around shared biomed...

With a contemporary smartphone, capturing, transmitting, and replicating sounds and visuals is a breeze, yet replicating scents remains elusive. If you want to change this, consider joining the 2025 DREAM Olfaction Challenge at www.synapse.org/Synapse:syn6....
@oldbap.bsky.social

After 21 years at my dream job, I’m very sad to announce my early retirement from the National Institutes of Health. My life’s work has been to scientifically study how our food environment affects what we eat, and how what we eat affects our physiology.

The final speaker lineup for the Philly Stand Up for Science Rally.

📢 TODAY’S THE DAY, PHILLY! 📢 We #standupforscience at 11 AM at City Hall!

We’ve got a great lineup of speakers for you (North Apron) and opportunities for other advocacy activities (Dillworth Park).

Hope to see you there!!
#standupforsciencephilly

Recalibrating Olfactory Neuroscience to the Range of Naturally Occurring Odor Concentrations Sensory systems enable organisms to detect and respond to environmental signals relevant for their survival and reproduction. A crucial aspect of any sensory signal is its intensity; understanding how...

Check out our review comparing typical experimental to naturally-occurring odor concentrations. You might be surprised.
www.jneurosci.org/content/45/1...
Thanks to Matt and Betty for asking me to take part!

What's Happening Inside the NIH and NSF

A long post about what’s happening to the science funding agencies in the US and why. As mentioned, this one just kept getting longer even as I kept stripping curse words from it.

www.science.org/content/blog...

a man with glasses and a black shirt says " it 's a small step that really goes a long way " ALT: a man with glasses and a black shirt says " it 's a small step that really goes a long way "

SOME GOOD NEWS ABOUT NIH FUNDING

Closed sessions of institute and center Advisory Counsel meetings are now permitted. This is where grant applications are discussed and approved for potential funding.

Open sessions where there are public presentations and discussions are still not allowed.

The Effect of Olfactory Disorder (and Other Chemosensory Disorders) on Perception, Acceptance, and Consumption of Food People with changes in the overall sensory experience of food often complain of taste disturbances, although the problem is normally caused by the loss of aroma in the food (thus an olfactory disorder...

Alexander Fjaeldstad and I have a new chapter in the book Smell, Taste, Eat: The Role of the Chemical Senses in Eating Behaviour, edited by @LorenzoDStafford. Lots of great insights here.

From our chapter, it’s clear that smell loss and its impact on ingestion remain vastly underexplored."

Olfaction with legs—Spiders use wall-pore sensilla for pheromone detection | PNAS The sense of smell is a central sensory modality of most terrestrial species. However, our knowledge of olfaction is based on vertebrates and insec...

doi.org/10.1073/pnas...
Olfaction in spiders. We found that the wall pore sensilla in spiders look similar from the outside to those of insects, but differ ultrastructurally in various ways. Independent evolution!
🧪

DeepNose: An Equivariant Convolutional Neural Network Predictive Of Human Olfactory Percepts The olfactory system employs responses of an ensemble of odorant receptors (ORs) to sense molecules and to generate olfactory percepts. Here we hypothesized that ORs can be viewed as 3D spatial filter...

Our DeepNose paper is in arxiv. In it, we present an equivariant CNN which can predict human olfactory perception based on molecular shapes, including mixtures. Comments/suggestions are very welcome.
arxiv.org/abs/2412.08747

A background in physics, and his own curiosity, have helped Dmitry Rinberg tackle the complexities of the neuroscience of smell. More on Rinberg sniffing out the mysteries of olfaction.

By Lina Zeldovich

www.thetransmitter.org/olfaction/sn...

The core figure, showing review counts from Publons data, indeed shows the intended effect but buries the lede:

No one uses Publons anymore.

Important paper!

www.biorxiv.org/content/bior...

Im not sure the Discussion fully delineates its radical implications.

No more...

* Place cells
* Grid cells, splitter cells, border cells
* Mirror neurons
* Reward neurons
* Conflict cells

(continued)

Hi Monica,
Could you please add me to the feed? I am an olfactory neuroscientist.
Here is my staff page: monell.org/joel-mainland/ and Scholar profile scholar.google.com/citations?us... Thank you!

Engineered receptors show how humans tell countless odour molecules apart The structures of engineered odorant receptors.

New paper in Nature showing how smell works in humans - no quantum woo involved, surprise surprise. Terrific stuff from Claire de March, Hiro Matsunami and others. Summarised here: www.nature.com/articles/d41...

My lab is looking for a postdoc to record lots of neurons while mice sniff each other. Basically I think that will tell us something more interesting about sensory processing than blasting pineapple smell into their noses. You don’t have to be an olfactionist to apply.

apply.interfolio.com/139308