Sachin Sethi

Is it possible to be invisible? Fiction is full of characters with the power to vanish. But some animals have real-life ways to become nearly invisible.

So excited to share a story I wrote for
@snexplores.bsky.social on how some animals make themselves (almost) invisible - and why humans can't do the same! My last piece written as a
@aaasmassmedia.bsky.social, and probably the one I had the most fun working on.
www.snexplores.org/article/how-...

29.01.2026 16:16 — 👍 3    🔁 2    💬 0    📌 0

Population-level calcium bumps in the fly brain can be driven by structured inhibition, & T-type Ca channels play a key role in computation which, in this case, means combining heading and wind direction. It’s also a nice example of how physiology doesn’t always fall out cleanly from the connectome.

06.01.2026 16:35 — 👍 6    🔁 1    💬 0    📌 0

Neuronal calcium spikes enable vector inversion in the Drosophila brain In the fly central complex, PFNa neurons switch from firing classical sodium spikes when depolarized to firing non-canonical T-type calcium spikes when hyperpolarized. This bidirectional spiking allow...

www.cell.com/cell/fulltex...

We had a lot of fun working on this project (led by Itzel Ishida, not on bluesky). Some interesting highlights from the paper -

06.01.2026 16:35 — 👍 53    🔁 25    💬 1    📌 2

On the left, the image shows a schematic of a fly head, ring neurons and EPG neurons together with some calcium imaging frames. On the right is a photo of a fly on a ball in virtual reality and another schematic of a VR system.

📢 Join us, the Haberkern lab, @uni-wuerzburg.de for a postdoc studying neural circuit mechanisms of navigation. You’ll spearheading neurophysiology experiments on our brand new 2P!

⏳ Apply by 28th February 2026

Details: www.haberkernlab.de/docs/ENPostd...

#neuroscience #academicjobs #postdoc

23.12.2025 11:27 — 👍 50    🔁 38    💬 3    📌 2

Schematic of how ER-EPG plasticity enables the bump of activity in EPGs to accurately track visual cues. As a fly makes a counter-clockwise turn (top to bottom) it will view visual cues (e.g. the sun) from a new angle and the EPG activity bump (red) will swing clockwise around the network by integrating self motion signals with these visual inputs. When the fly faces a different angle, distinct visual ER neurons are active. Plasticity forms a trough of weak synapses (large circles - strong synapses, small circles - weak synapses) that allow ER neurons with distinct visual tuning to move the EPG bump via disinhibition.

*First preprint from our lab* !!!!!
How does the brain learn to anchor its internal sense of direction to the outside world? 🧭
led by Mark Plitt @markplitt.bsky.social & Dan Turner-Evans, w/ Vivek Jayaraman:
“Octopamine instructs head direction plasticity” www.biorxiv.org/content/10.6...
Thread ⬇️

15.12.2025 18:26 — 👍 140    🔁 51    💬 3    📌 4