@jhawkins and @hlee led a brainstorming session around the nature of reference frames and how they work in the brain. They discussed papers on grid cells and explored how grid cell and place cell mechanisms could lead to representing reference frames in the neocortex. This was a high-level exploratory discussion, with no conclusions drawn.
Summary Video
Main Video
0:00 Introduction
2:26 Overview of Challenges We’re Working on Related to Reference Frames
4:02 How We Used to Think About Reference Frames in the Biological Model: Layer 4, Layer 6A & Grid Cells
6:06 Back to the Drawing Board: Thinking about Grid Cells and Place Cells
8:28 Grid Cells Are Anchored by Environmental Distal Cues
15:06 Place Cells Are Also Mapped from Environmental Distal Cues
16:31 More than One Grid Cell Module Is Needed to Get a Good Reference Frame Mapping
17:54 Reviewing Two Papers on Grid Cell Remapping
25:43 An In-Depth Exploration of the Computational Model Used for Grid and Place Cells
37:01 The Lykken 2025 Paper
49:09 Summarizing how We’re Currently Thinking about Biological Reference Frames
53:40 Some Speculations on how Location Is Represented in the Brain
58:19 Some More Speculative Thoughts on Biological Reference Frames
1:01:58 A Possible Model to Think About Biological Reference Frames
1:07:52 One More Paper: A Novel Somatosensory Spatial Navigation System Outside the Hippocampal Formation
1:12:15 Final Thoughts on Biological Reference Frames