While adults might be spending the weekend trying to remember where they have hidden a hoard of Easter eggs, the black-capped chickadee has no trouble recalling where its treats are stashed. Now researchers have discovered why: the diminutive birds create a barcode-like memory each time they stash food.
Black-capped chickadees are known for tucking food away during the warmer months – with some estimates suggesting a single bird can hide up to 500,000 food items a year. But more remarkable still is their reliability in finding the morsels again.
Now researchers say they have unpicked the mechanism behind the feat. Writing in the journal Cell scientists in the US report how they gave chickadees sporadic access to sunflower seeds within an arena featuring more than 120 locations where food could be stashed.
The behaviour of the birds and the activity at each cache site – be it the storage of food, retrieval of food or checks on a stash – were recorded on video.
The team used an implanted probe in the brain of each bird to record the activity of neurons in its hippocampus – a brain structure crucial for memory formation.
The results show that each time a bird stashed seeds, even if it was in the same location, a different combination of neurons fired in its hippocampus, resulting in a barcode-like pattern of activity.
The same "barcode" was observed when the morsel was retrieved as for when it was cached.
The barcodes were distinct from place cells – neurons in the hippocampus known to be involved in the formation of memories involving specific locations. "The two overlapped randomly so that neurons could be neither, either, or both," said Dr Selmaan Chettih of Columbia University's Zuckerman Institute, first author of the study.
[...] "These results suggest that the barcode represents a specific episodic experience, unique in place and time in the chickadee's life," the researchers report.
Journal Reference:
Selmaan N. Chettih et al., Barcoding of episodic memories in the hippocampus of a food-caching bird, Cell, Published:March 29, 2024 DOI: https://doi.org/10.1016/j.cell.2024.02.032
(Score: 4, Funny) by mhajicek on Tuesday April 02 2024, @01:59AM (1 child)
They're using the same system I use for milling cutter inventory.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 5, Interesting) by JoeMerchant on Tuesday April 02 2024, @01:39PM
Well, instead of ink on labels, the researchers are seeing neural activity (likely recorded by a single electrode) over time, which they're calling a "bar code" but in reality they're getting a time-series representation of what's happening in 3D around the probe.
For a couple of decades now, there has been a "repeating music" theory of both neural processing / decision making and memory storage. The different layers of neural processing take a set of inputs which cause the present layer to react in a certain (often repeating) pattern. That firing pattern then - eventually - triggers the next layer to start firing its own pattern and so on until you start activating motor neurons, or encode a memory, etc. When memory is involved, something (quite amazing) "looks up" the appropriate memory which is recalled as a similar (just ask a collection of eye-witnesses: it's not exact) firing pattern which then gets incorporated into whatever activity called up that memory's chorus of decisions eventually triggering the motor responses.
So, these researchers managed to plant a probe somewhere near the chickadee's memory center and observed similar firing patterns during memory storage and recall. Cool.
What's more amazing to me than the human brain, which has roughly as many neurons as there are stars in the Milky Way, are creatures like wasps which manage all their complex behaviors from optical and smell based 3D flight navigation to nest building etc. on 5000 neurons or less. Then we can consider what sperm whales might be doing with over 6x the brain mass of humans...
🌻🌻 [google.com]
(Score: 1) by khallow on Tuesday April 02 2024, @02:49AM (2 children)
What happens when they check on a stash, and it's not there? Wonder if they have a way of keeping track of which hiding spots get busted?
(Score: 4, Informative) by Anonymous Coward on Tuesday April 02 2024, @03:12AM (1 child)
They try other spots? Some do remember which spots are empty among other things.
https://northernwoodlands.org/outside_story/article/brainy-birds-stash-stores-thieves [northernwoodlands.org]
https://www.cam.ac.uk/research/news/hushed-hoarders-and-prying-pilferers [cam.ac.uk]
https://arstechnica.com/science/2016/01/crows-the-tail-pulling-food-stealing-bird-prodigies/ [arstechnica.com]
(Score: 1, Interesting) by Anonymous Coward on Tuesday April 02 2024, @03:56PM
Sounds like bird memory includes garbage collection...