Unexpected changes in learned task contingencies trigger sharp wave ripples in the primate hippocampus during virtual navigation
Bibliographic record
Abstract
Abstract The hippocampi and mesial temporal lobes play a central role in episodic memory and associative learning. It is unclear how unexpected experience influences learning. Hippocampal sharp wave ripples (SWR) are an electrical biomarker of memory consolidation. We tracked when and where SWR occur during 2 tasks. Local field potentials were recorded in the hippocampi, entorhinal cortices and amygdalae of non-human primates (NHP; n=3) performing reversal and associative learning tasks in a 3D virtual environment. Our results show hippocampal SWR occurred when learned task contingencies were unexpectedly altered. Surprise rewards and reward denial were associated with SWR rates 9.8x and 8.0x greater than expected rewards. The highest density of SWR occurred in zones where errors were made. SWR were preceded by event-related potentials in the amygdala but not entorhinal cortex. Our results suggest that SWR generation in primates may prioritize behaviourally relevant experience for commitment to memory to allow flexible learning.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.016 | 0.018 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.003 | 0.006 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.004 | 0.004 |
| Research integrity | 0.001 | 0.013 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".