Skip to main content
Dryad logo

Data From: Fear conditioning potentiates the Hippocampal CA1 commissural pathway In vivo and increases awake phase sleep

Citation

Subramaniyan, Manivannan et al. (2021), Data From: Fear conditioning potentiates the Hippocampal CA1 commissural pathway In vivo and increases awake phase sleep, Dryad, Dataset, https://doi.org/10.5061/dryad.sj3tx965f

Abstract

The hippocampus is essential for spatial learning and memory. To assess learning we used contextual fear conditioning (cFC), where animals learn to associate a place with aversive events like foot-shocks. Candidate memory mechanisms for cFC are long-term potentiation and long-term depression, but there is little direct evidence of them operating in the hippocampus in vivo following cFC. Also, little is known about the behavioral state changes induced by cFC. To address these issues, we recorded local field potentials in freely behaving mice by stimulating in the left dorsal CA1 region and recording in the right dorsal CA1 region. Synaptic strength in the commissural pathway was monitored by measuring field excitatory postsynaptic potentials (fEPSPs) before and after cFC. After cFC, the commissural pathway’s synaptic strength was potentiated. Although recordings occurred during the wake phase of the light/dark cycle, the mice slept more in the post-conditioning period than in the pre-conditioning period. Relative to awake periods, in non-rapid eye movement (NREM) sleep the fEPSPs were larger in both pre- and post-conditioning periods. We also found a significant negative correlation between the animal’s speed and fEPSP size. Therefore, to avoid confounds in the fEFSP potentiation estimates, we controlled for speed-related and sleep-related fEPSP changes and still found that cFC induced long-term potentiation, but no significant long-term depression. Synaptic strength changes were not found in the control group that simply explored the fear-conditioning chamber, indicating that exploration of the novel place did not produce the measurable effects caused by cFC. These results show that following cFC, the CA1 commissural pathway is potentiated, likely contributing to the functional integration of the left and right hippocampi in fear memory consolidation. In addition, the cFC paradigm produces significant changes in an animal’s behavioral state, which are observable as proximal changes in sleep patterns.

Methods

The data were collected from mice during different behavioral states before and after fear conditioning. In vivo field recording was used to measure changes in field potentials (fEPSP). Data were processed in MATLAB and submitted here in .mat file extension.

Usage Notes

Users should read the original research article associated with this dataset in order to understand this data set.

Funding

Chernowitz Medical Research Foundation

National Institute of Neurological Disorders and Stroke, Award: R01NS021229

National Institute on Alcohol Abuse and Alcoholism, Award: R01AA026267

Chernowitz Medical Research Foundation