4 ms·

as for 'storage of durations' mentioned in the interview there is a well known paper on "time cells" in the hippocampus [0] by Howard Eichenbaum et al. which do

as for 'storage of durations' mentioned in the interview there is a well known paper on "time cells" in the hippocampus [0] by Howard Eichenbaum et al. which doesn't seem to refer to Purkinje cells (which only exist in the cerebellum [1]). There is significant evidence for temporal memory maintained in the hippocampus and entorhinal cortex [2], just like grid cells[3] in the hippocampus used as coordinate system for spatial and abstract navigation [4] while time cells facilitate "navigation" in temporal dimension. [0] Hippocampal "time cells" bridge the gap in memory for discontiguous events https://pubmed.ncbi.nlm.nih.gov/21867888/ https://pubmed.ncbi.nlm.nih.gov/21867888/ [1] Basic anatomy of human memory https://courses.lumenlearning.com/wsu-sandbox/chapter/parts-of-the-brain-involved-with-memory/ https://courses.lumenlearning.com/wsu-sandbox/chapter/parts-... [2] Time cells in the human hippocampus and entorhinal cortex support episodic memory https://www.pnas.org/content/117/45/28463 https://www.pnas.org/content/117/45/28463 [3] Grid cells: http://www.scholarpedia.org/article/Grid_cells http://www.scholarpedia.org/article/Grid_cells [4] Time (and space) in the hippocampus https://www.sciencedirect.com/science/article/pii/S2352154616302819 https://www.sciencedirect.com/science/article/pii/S235215461...

pishpash 6y ago
Truly, I believe there are multiple architectures for information processing in the body, and not only in the brain/neurons. Think of the computing landscape where you have a salad bowl of ANN's implemented on TPU's, some GPU's, some specialized ASIC's, DSP's, some CPU's. There is no reason to believe efficient information encoding through evolution ends up with one architecture. It's going to turn out to be as varied as the differentiated cells in the body, though there may be some unification in foundational units at the equivalent level of transistors of something, maybe some molecular machinery that stores a bit or activates a switch. Presumably that's what Gallistel is looking for. It does seem wasteful for a whole neuron to be the basic unit of information processing, so I agree there should be something more atomic inside.
- seesawtron 6y ago
  That is an interesting line of thought. Cortex and non-cortical regions are somewhat different in terms of their cell types composition which could inherently support different computation and learning mechanisms.
- avocad 6y ago
  I always saw the hormones that regulate our emotions as primitive forms of memory, older than neurons. So an organism can remain in a certain state for a while. There is also the possibility that RNA is used for memory: https://www.bbc.com/news/science-environment-44111476 https://www.bbc.com/news/science-environment-44111476

pishpash 6y ago

Truly, I believe there are multiple architectures for information processing in the body, and not only in the brain/neurons. Think of the computing landscape where you have a salad bowl of ANN's implemented on TPU's, some GPU's, some specialized ASIC's, DSP's, some CPU's. There is no reason to believe efficient information encoding through evolution ends up with one architecture. It's going to turn out to be as varied as the differentiated cells in the body, though there may be some unification in foundational units at the equivalent level of transistors of something, maybe some molecular machinery that stores a bit or activates a switch. Presumably that's what Gallistel is looking for. It does seem wasteful for a whole neuron to be the basic unit of information processing, so I agree there should be something more atomic inside.

seesawtron 6y ago
That is an interesting line of thought. Cortex and non-cortical regions are somewhat different in terms of their cell types composition which could inherently support different computation and learning mechanisms.
avocad 6y ago
I always saw the hormones that regulate our emotions as primitive forms of memory, older than neurons. So an organism can remain in a certain state for a while. There is also the possibility that RNA is used for memory: https://www.bbc.com/news/science-environment-44111476 https://www.bbc.com/news/science-environment-44111476