4 ms·

I suggest starting with the works by Howard Eichenbaum on memory and Edvard & May-Britt Moser (and John O'Keefe and Lynn Nadel) on place & grid cells. For th

I suggest starting with the works by Howard Eichenbaum on memory and Edvard & May-Britt Moser (and John O'Keefe and Lynn Nadel) on place & grid cells. For the latest and greatest see https://twitter.com/doellerlab https://twitter.com/doellerlab https://twitter.com/KordingLab https://twitter.com/KordingLab https://twitter.com/preston_lab https://twitter.com/preston_lab https://twitter.com/memorylab https://twitter.com/memorylab https://twitter.com/ptoncompmemlab https://twitter.com/ptoncompmemlab https://twitter.com/MillerLabMIT https://twitter.com/MillerLabMIT https://twitter.com/hugospiers https://twitter.com/hugospiers Once you start pulling that thread you'd be surprised how much we do know.

p1esk 6y ago
Unless you know of working implementations of memory algorithms I tend to agree that we have no clue how memory works.
- deleted 6y ago
  [deleted]
- andyxor 6y ago
  that's called being lazy
TaupeRanger 6y ago
Literally nothing you posted surprises me in the least, and literally none of this work shows that we know anything at all about how memory is implemented. Perhaps read some of the many takedowns of so called "grid cells" which show that it is completely unsurprising and not at all interesting or noteworthy that activity in some parts of the brain correlates with location information. The important questions always remain unanswered.
eli_gottlieb 6y ago
We know a fair bit about how cognitive maps work in 2D and 3D Euclidean environments. We know damn little about how nontrivial manifold structure can be learned, particularly in spaces with more than three dimensions.
- andyxor 6y ago
  spatial cognitive maps used for navigation are extendable to arbitrarily high dimensional spaces for abstract concept representation, using pretty much the same machinery. There is a ton of work on this, both theory and empirical evidence, here are just a few: "Navigating cognition: Spatial codes for human thinking" https://science.sciencemag.org/content/362/6415/eaat6766.abstract https://science.sciencemag.org/content/362/6415/eaat6766.abs... "Organizing conceptual knowledge in humans with a gridlike code" https://science.sciencemag.org/content/352/6292/1464 https://science.sciencemag.org/content/352/6292/1464 "The Hippocampus Encodes Distances in Multidimensional Feature Space" https://www.sciencedirect.com/science/article/pii/S0960982219302052 https://www.sciencedirect.com/science/article/pii/S096098221... "A non-spatial account of place and grid cells based on clustering models of concept learning" https://www.nature.com/articles/s41467-019-13760-8 https://www.nature.com/articles/s41467-019-13760-8 "A learned map for places and concepts in the human MTL" https://www.biorxiv.org/content/10.1101/2020.06.15.152504v1.abstract https://www.biorxiv.org/content/10.1101/2020.06.15.152504v1.... "What Is a Cognitive Map? Organizing Knowledge for Flexible Behavior" https://www.sciencedirect.com/science/article/pii/S0896627318308560 https://www.sciencedirect.com/science/article/pii/S089662731... "A map of abstract relational knowledge in the human hippocampal–entorhinal cortex" https://elifesciences.org/articles/17086 https://elifesciences.org/articles/17086 "Map-Like Representations of an Abstract Conceptual Space in the Human Brain" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884611/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884611/ "Knowledge Across Reference Frames: Cognitive Maps and Image Spaces" https://www.sciencedirect.com/science/article/pii/S1364661320301327 https://www.sciencedirect.com/science/article/pii/S136466132... "Concept formation as a computational cognitive process" https://www.sciencedirect.com/science/article/pii/S235215462030190X https://www.sciencedirect.com/science/article/pii/S235215462... "Efficient and flexible representation of higher-dimensional cognitive variables with grid cells" https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1007796 https://journals.plos.org/ploscompbiol/article?id=10.1371/jo... "The cognitive map in humans: spatial navigation and beyond" https://www.nature.com/articles/nn.4656 https://www.nature.com/articles/nn.4656 "A general model of hippocampal and dorsal striatal learning and decision making" https://www.pnas.org/content/117/49/31427.short https://www.pnas.org/content/117/49/31427.short "On the Integration of Space, Time, and Memory" https://www.sciencedirect.com/science/article/pii/S0896627317305603 https://www.sciencedirect.com/science/article/pii/S089662731...

p1esk 6y ago

Unless you know of working implementations of memory algorithms I tend to agree that we have no clue how memory works.

deleted 6y ago
[deleted]
andyxor 6y ago
that's called being lazy

TaupeRanger 6y ago

Literally nothing you posted surprises me in the least, and literally none of this work shows that we know anything at all about how memory is implemented. Perhaps read some of the many takedowns of so called "grid cells" which show that it is completely unsurprising and not at all interesting or noteworthy that activity in some parts of the brain correlates with location information. The important questions always remain unanswered.

eli_gottlieb 6y ago

We know a fair bit about how cognitive maps work in 2D and 3D Euclidean environments. We know damn little about how nontrivial manifold structure can be learned, particularly in spaces with more than three dimensions.

andyxor 6y ago
spatial cognitive maps used for navigation are extendable to arbitrarily high dimensional spaces for abstract concept representation, using pretty much the same machinery. There is a ton of work on this, both theory and empirical evidence, here are just a few: "Navigating cognition: Spatial codes for human thinking" https://science.sciencemag.org/content/362/6415/eaat6766.abstract https://science.sciencemag.org/content/362/6415/eaat6766.abs... "Organizing conceptual knowledge in humans with a gridlike code" https://science.sciencemag.org/content/352/6292/1464 https://science.sciencemag.org/content/352/6292/1464 "The Hippocampus Encodes Distances in Multidimensional Feature Space" https://www.sciencedirect.com/science/article/pii/S0960982219302052 https://www.sciencedirect.com/science/article/pii/S096098221... "A non-spatial account of place and grid cells based on clustering models of concept learning" https://www.nature.com/articles/s41467-019-13760-8 https://www.nature.com/articles/s41467-019-13760-8 "A learned map for places and concepts in the human MTL" https://www.biorxiv.org/content/10.1101/2020.06.15.152504v1.abstract https://www.biorxiv.org/content/10.1101/2020.06.15.152504v1.... "What Is a Cognitive Map? Organizing Knowledge for Flexible Behavior" https://www.sciencedirect.com/science/article/pii/S0896627318308560 https://www.sciencedirect.com/science/article/pii/S089662731... "A map of abstract relational knowledge in the human hippocampal–entorhinal cortex" https://elifesciences.org/articles/17086 https://elifesciences.org/articles/17086 "Map-Like Representations of an Abstract Conceptual Space in the Human Brain" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884611/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884611/ "Knowledge Across Reference Frames: Cognitive Maps and Image Spaces" https://www.sciencedirect.com/science/article/pii/S1364661320301327 https://www.sciencedirect.com/science/article/pii/S136466132... "Concept formation as a computational cognitive process" https://www.sciencedirect.com/science/article/pii/S235215462030190X https://www.sciencedirect.com/science/article/pii/S235215462... "Efficient and flexible representation of higher-dimensional cognitive variables with grid cells" https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1007796 https://journals.plos.org/ploscompbiol/article?id=10.1371/jo... "The cognitive map in humans: spatial navigation and beyond" https://www.nature.com/articles/nn.4656 https://www.nature.com/articles/nn.4656 "A general model of hippocampal and dorsal striatal learning and decision making" https://www.pnas.org/content/117/49/31427.short https://www.pnas.org/content/117/49/31427.short "On the Integration of Space, Time, and Memory" https://www.sciencedirect.com/science/article/pii/S0896627317305603 https://www.sciencedirect.com/science/article/pii/S089662731...