Mammals Natural 3D Compass Shown In Bats And Represented With Donuts

Scientists study the ‘3D head direction’ cell in bat and use a donut to explain how it works. via theverge

Picture yourself exiting a subway car. You step onto the platform and for a moment, you’re completely disoriented. It feels weird, because when you entered the car at another station, you knew north from south, but now you’re turned around. According to researchers at Weizmann Institute of Science in Israel, that feeling is likely caused by a temporary failure in what they think is the mammalian brain’s 3D compass — a compass that doesn’t rely on a magnetic field, but that orients our brains relative to our surroundings. And as it turns out, the best way to represent this 3D compass is by modeling it after a donut.

To understand how animals orient themselves in three dimensions, the researchers studied bats. These mammals are an ideal choice, because they need to be able to locate themselves in space even when they are flying with their bellies pointing toward the sky. To figure out how bats achieve this navigational feat, the researchers used a video-monitoring system and microelectrodes that they inserted in the bats’ brains. These electrodes transmitted brain signals during flight and helped the researchers track the animals’ head rotation. The resulting readings allowed the researchers to identify neurons within the bat’s brain that are tuned to specific 3D angles, sort of like a 3D vector. Moreover, the researchers realized that those neurons are located in a different region of the brain than those used to compute head directions in 2D — a finding that indicates that these two parameters are computed independently from each other.

“Basically what we found is that if you want to direct your head at a tree branch that’s at a certain elevation and angle from you,” says Arseny Finkelstein, a neuroscientist at the Weizmann Institute and a co-author of the bat navigation study published in Nature today, “you [will] want to compute this [in a] 3D direction. This ‘3D head direction cell’ can do that.”

Humans are obviously very different from bats, but Finkelstein thinks that it’s entirely possible that the human brain possesses the same type of 3D compass. Even though we can’t fly without the help of technology, we live in multi-layered environments — buildings with multiple floors are one example — and that means that being able to understand and process elevation, as well as direction in 3D is crucial.

That’s why discovering these “3D head direction cells” is so important. Until recently, our understanding of navigation was limited to cells that can help us form a mental map of our surroundings, as well as cells that help our brains navigate on a horizontal plane. But little was known about which cells work in combination with our mental maps to allow navigation in 3D. “This was never identified in any species, not just bats, but in mammalians species,” Finkelstein says. “Part of that was just because it used to be hard to track those angles — there was a technological gap.” But advancements in recording technology allowed this study to go forward. And the information that the researchers gathered is what lead to them to model the mammalian mental compass in the shape of a donut.

“It’s not an anatomical structure, but a functional representation,” Finkelstein says. “It’s the structure that we think these neurons follow. It’s how they work together.” The donut model is ideal, Finkelstein says, because it gives animals a lot of information about when their heads are inverted. A sphere wouldn’t be as detailed. “That’s a mathematical argument,” Finkelstein says. But it’s also based on biological necessity. “The animal cares about this information.”

According to David Rowland and May-Britt Moser, two neuroscientists at the Norwegian University of Science and Technology who didn’t participate in this study, the researchers’ work “demonstrates the immeasurable value” of using an animal behavior approach to study neuroscience. “By studying an animal that behaves in 3D,” they wrote in a news story for Nature published today, “[Finkelstein and colleagues] have discovered one way in which the mammalian brain orients in 3D.”

Read more


Halloween season is here!
Halloween season is here! Check out all the posts, gift guides, and more!

Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards

Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7:30pm ET! To join, head over to YouTube and check out the show’s live chat and our Discord!

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Join over 38,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython – The easiest way to program microcontrollers – CircuitPython.org


New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — NEW PRODUCT – Adafruit RP2350 22-pin FPC HSTX to DVI Adapter for HDMI Displays

Python for Microcontrollers – Adafruit Daily — Python on Microcontrollers Newsletter: Adafruit Grand Opening, Profile MicroPython Memory and More! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi — Classic editor

EYE on NPI – Adafruit Daily — EYE on NPI Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

Adafruit IoT Monthly — Garden Lights, Bluetooth 6.0, and more!

Maker Business – Adafruit Daily — A look at Boeing’s supply chain and manufacturing process

Electronics – Adafruit Daily — When do I use X10?

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !



No Comments

No comments yet.

Sorry, the comment form is closed at this time.