If you do a little research about grid cells, you’ll find there many types of cells that deal with representing some core spatial aspect of reality (location, space, direction, proximity, speed, distance). I think it is fun to think about gravity in this context, because if brains evolved with different gravity, or no gravity, or multiple gravitational pulls, the version or projection of reality we would understand would be vastly different at a core cellular level. All because these processes evolved over millions of years in a different gravitational environment.
So basically grid cells are just cells that learn to respond to a certain specific stimulus or input pattern? Given that it is possible the specific stimulus may be realized by the grid cell in an indirect manner.
rhyo, I think in evolutionary terms. The first simple life in the ocean had to deal only with up and down and sunlight. What time of day should I be close to the surface? What time of day should I be close to the sea floor. To me the diurnal cycle and up/down should be very deep in biology on earthly life.
Quadrupeds should be basically two-dimensional thinkers. Monkeys and the descendants of monkeys that lived in trees, that navigated in a 3D environment, should be three dimensional thinkers. Whether we have lost three dimensional thinking from our millions of years of 2D walking I do not know.
I think we’ve had it ever since we had opposable thumbs and starting building tools. You need a proper representation of 3D space to build tools.
Yes, and fish live in a completely 3D world.
I’ve assumed a long time that we humans and probably most mammals have a proper 3D “bucky ball” style grid cell representation of space. There is some evidence in bats of place cells that project into 3D space.
Despite those core cellular optimisations though, it’s also remarkable how quickly the brain can cope with a change in one of those constants, e.g. if you went to the moon (I’m yet to try this myself).
Do the grid cells employ some sort of gravity detection system like statoliths …used by plants?
Not directly. The gravity detection systems are both postural and from the vestibular system. These are both senses that are sensed somewhat like vision or hearing. There are several layers of processing before this is digested to the level of being fed into the grid-forming cortex areas.
Ok thanks…that makes more sense…probably a lot faster too.