Izumi Fukunaga
@ifukunaga.bsky.social
570 followers 390 following 30 posts
Neuroscientist with interests in olfaction, circuits, neurophysiology of behavior, and more. Associate professor at OIST. Profile: https://www.oist.jp/research/research-units/sbn/izumi-fukunaga Lab: https://www.oist.jp/research/research-units/sbn
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Reposted by Izumi Fukunaga
andreas-t-schaefer.bsky.social
Lots of exciting clinical PhD projects at Crick - including the opportunity for neurosurgeons to work with us and record electrical activity in patients with neuropixels probes. Please share widely!
crick.ac.uk
We're looking for clinicians who are passionate about research to join our 3-year fully funded clinical PhD programme. 🔬🩺

Apply by 14 November 2025. 👇

www.crick.ac.uk/careers-stud...
Doctoral clinical fellows
The Crick's clinical PhD programme.
www.crick.ac.uk
Reposted by Izumi Fukunaga
neurovenki.bsky.social
(edited repost) Thrilled to see our computational work on adaptive shaping of behavior (we call it outcome-based curriculum learning) in PLoS Comp Biol! @wl-tong.bsky.social, @gautamreddy.bsky.social & I formalize curricula in any RL task that can be framed as sequential simple-to-complex behavior.
Adaptive algorithms for shaping behavior
Author summary Animals are commonly trained by ‘shaping’ their behavior using a sequence of simpler tasks towards a complex behavior. Numerous schools of thought have proposed heuristics for shaping b...
journals.plos.org
Reposted by Izumi Fukunaga
simonepigolotti.bsky.social
Open faculty positions in Physics at OIST
oistedu.bsky.social
📢 #FacultyHiring: OIST is hiring! We invite exceptional scientists to apply for faculty positions in:
- Ecology, Environmental Science, Earth Science, and Oceanography
- Physics and Quantum Science (including related fields)
🔗: www.oist.jp/careers/facu...
Reposted by Izumi Fukunaga
neurovenki.bsky.social
We watched mice follow scent trails drawn on an “endless” treadmill. By manipulating trail geometry/statistics, perturbing mouse nose & brain, and modeling behavior with a Bayesian framework, we show that mice use predictive (rather than reactive) strategies.
Reposted by Izumi Fukunaga
Reposted by Izumi Fukunaga
oistedu.bsky.social
Tiny changes in our brain chemistry sets us apart from Neanderthals and Denisovans – and when introduced into mice, seem to help females compete better for scarce resources 🧠 Read about how ADSL may have influenced our evolution www.oist.jp/news-center/...
Tracing brain chemistry across humanity’s family tree
Small changes to an enzyme suggest how modern humans differ from Neanderthals and Denisovans in biochemistry and behavior.
www.oist.jp
ifukunaga.bsky.social
We don’t yet understand how our findings translate to human behavior and cognition, but hopefully they offer clues to our origins.

Grateful for the opportunity to take part in this fascinating collaborative work and to @oistedu.bsky.social for all the support.
ifukunaga.bsky.social
What’s more, another mutation in the non coding region - also positively selected - reduces the ADSL expression in humans. So, reduction in the ADSL activity seems overall beneficial.
ifukunaga.bsky.social
Turns out this mutation reduces the stability of the enzyme.

When the “humanised” ADSL was introduced into the mouse, the enzyme substrates increased particularly in the brain, and female mice became adept at accessing a scarce resource (in this case, water in the cage).
ifukunaga.bsky.social
ADSL is an enzyme crucial for purine biosynthesis.

As the modern human lineage split from those of Neanderthals and Denisovans, a single amino acid mutation in this enzyme became fixed.
ifukunaga.bsky.social
Talking of understanding the brain in the evolutionary context…

We have a new study out, led by Xiang-Chun Ju in Svante Pääbo’s lab at OIST:

The activity and expression of adenylosuccinate lyase were reduced during modern human evolution, affecting brain and behavior

www.pnas.org/doi/10.1073/...
PNAS
Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans...
www.pnas.org
Reposted by Izumi Fukunaga
farrowlab.bsky.social
Fantastic to see this collaborative work with Hopi Hoekstra out in Nature (tinyurl.com/3at3zvby). Lead by @felixbaier.bsky.social and @katjareinhard.bsky.social. Not possible without @bramnuttin.bsky.social , Chen Liu and @arnausd.bsky.social.

Excited to see where this work leads.
ifukunaga.bsky.social
Thank you Andreas and also for your very helpful feedback!
ifukunaga.bsky.social
P.s., some colleagues in the field consider this study controversial :) We have tried our best to respond to the comments in the limited time we had. We would very much like to hear if others get a different result. An open discourse like that might help move the field forward.
ifukunaga.bsky.social
Of course, we have not exhausted all possible ways of activating the olfactory bulb output. The encoding format may well depend on the downstream regions involved. There’s plenty more to do!

Congratulations to Xiaochen Fu and all authors!
ifukunaga.bsky.social
What does this mean?

Sniff rhythms may not provide clock-like reference signals in downstream areas.

Rather, with progressive stages of olfactory processing, the system may rely more on firing rates and synchrony, with the sniff rhythm serving a more nuanced, modulatory role.
ifukunaga.bsky.social
We found that, when the activity bypasses the olfactory bulb, mice can discriminate between:

✅ spike counts
✅ synchrony
❌ timing relative to respiratory cycle

This result is surprising because sniff-locking is prevalent in the output of the olfactory bulb.
ifukunaga.bsky.social
Animals’ sniffing drives rhythmic input to the olfactory system.

How does this timing contribute to perception, especially beyond first steps of olfactory processing?

We tested this using simple closed-loop optogenetics in our new paper: www.cell.com/iscience/ful...
Decoding olfactory bulb output: A behavioral assessment of rate, synchrony, and respiratory phase coding
Neurogenetics; Behavioral neuroscience; Sensory neuroscience
www.cell.com
Reposted by Izumi Fukunaga
neuroluci.bsky.social
How do brain circuits evolve? We started looking for some answers by using synapse-resolution cross-species comparative connectomics on an entire olfactory circuit 👇

bit.ly/44aVm9E
ifukunaga.bsky.social
For students in USA who are affected by the current situation:

OIST Graduate School is accepting special applications right now.

Deadline June 15, 2025

www.oist.jp/admissions/s...
Special Application Deadline for Students Accepted or Studying in the United States
www.oist.jp