Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle
Circadian rhythm misalignment has a deleterious impact on the brain and the body. In rats, exposure to a 21-hour day length impairs hippocampal dependent memory. Sleep, and particularly K-complexes and sleep spindles in the cortex, have been hypothesized to be involved in memory consolidation. Alter...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2020-10-01
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| Series: | Frontiers in Neuroscience |
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| Online Access: | https://www.frontiersin.org/article/10.3389/fnins.2020.551843/full |
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| author | Scott H. Deibel Ryan Rota Hendrik W. Steenland Hendrik W. Steenland Karim Ali Bruce L. McNaughton Bruce L. McNaughton Masami Tatsuno Robert J. McDonald |
| author_facet | Scott H. Deibel Ryan Rota Hendrik W. Steenland Hendrik W. Steenland Karim Ali Bruce L. McNaughton Bruce L. McNaughton Masami Tatsuno Robert J. McDonald |
| author_sort | Scott H. Deibel |
| collection | DOAJ |
| description | Circadian rhythm misalignment has a deleterious impact on the brain and the body. In rats, exposure to a 21-hour day length impairs hippocampal dependent memory. Sleep, and particularly K-complexes and sleep spindles in the cortex, have been hypothesized to be involved in memory consolidation. Altered K-complexes, sleep spindles, or interaction between the cortex and hippocampus could be a mechanism for the memory consolidation failure but has yet to be assessed in any circadian misalignment paradigm. In the current study, continuous local field potential recordings from five rats were used to assess the changes in aspects of behavior and sleep, including wheel running activity, quiet wakefulness, motionless sleep, slow wave sleep, REM sleep, K-complexes and sleep spindles, in rats exposed to six consecutive days of a T21 light-dark cycle (L9:D12). Except for a temporal redistribution of sleep and activity during the T21, there were no changes in period, or total amount for any aspect of sleep or activity. These data suggest that the memory impairment elicited from 6 days of T21 exposure is likely not due to changes in sleep architecture. It remains possible that hippocampal plasticity is affected by experiencing light when subjective circadian phase is calling for dark. However, if there is a reduction in hippocampal plasticity, changes in sleep appear not to be driving this effect. |
| first_indexed | 2024-12-12T13:08:23Z |
| format | Article |
| id | doaj.art-62329df52758461e9e0669005683ccaf |
| institution | Directory Open Access Journal |
| issn | 1662-453X |
| language | English |
| last_indexed | 2024-12-12T13:08:23Z |
| publishDate | 2020-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Neuroscience |
| spelling | doaj.art-62329df52758461e9e0669005683ccaf2022-12-22T00:23:35ZengFrontiers Media S.A.Frontiers in Neuroscience1662-453X2020-10-011410.3389/fnins.2020.551843551843Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark CycleScott H. Deibel0Ryan Rota1Hendrik W. Steenland2Hendrik W. Steenland3Karim Ali4Bruce L. McNaughton5Bruce L. McNaughton6Masami Tatsuno7Robert J. McDonald8Department of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaDepartment of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaDepartment of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaNeuroTek Innovative Technology Inc., Toronto, ON, CanadaDepartment of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaDepartment of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaDepartment of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United StatesDepartment of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaDepartment of Neuroscience, University of Lethbridge, Lethbridge, AB, CanadaCircadian rhythm misalignment has a deleterious impact on the brain and the body. In rats, exposure to a 21-hour day length impairs hippocampal dependent memory. Sleep, and particularly K-complexes and sleep spindles in the cortex, have been hypothesized to be involved in memory consolidation. Altered K-complexes, sleep spindles, or interaction between the cortex and hippocampus could be a mechanism for the memory consolidation failure but has yet to be assessed in any circadian misalignment paradigm. In the current study, continuous local field potential recordings from five rats were used to assess the changes in aspects of behavior and sleep, including wheel running activity, quiet wakefulness, motionless sleep, slow wave sleep, REM sleep, K-complexes and sleep spindles, in rats exposed to six consecutive days of a T21 light-dark cycle (L9:D12). Except for a temporal redistribution of sleep and activity during the T21, there were no changes in period, or total amount for any aspect of sleep or activity. These data suggest that the memory impairment elicited from 6 days of T21 exposure is likely not due to changes in sleep architecture. It remains possible that hippocampal plasticity is affected by experiencing light when subjective circadian phase is calling for dark. However, if there is a reduction in hippocampal plasticity, changes in sleep appear not to be driving this effect.https://www.frontiersin.org/article/10.3389/fnins.2020.551843/fullsleepcircadian rhythmsratsmemorycircadian misalignment |
| spellingShingle | Scott H. Deibel Ryan Rota Hendrik W. Steenland Hendrik W. Steenland Karim Ali Bruce L. McNaughton Bruce L. McNaughton Masami Tatsuno Robert J. McDonald Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle Frontiers in Neuroscience sleep circadian rhythms rats memory circadian misalignment |
| title | Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle |
| title_full | Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle |
| title_fullStr | Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle |
| title_full_unstemmed | Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle |
| title_short | Assessment of Sleep, K-Complexes, and Sleep Spindles in a T21 Light-Dark Cycle |
| title_sort | assessment of sleep k complexes and sleep spindles in a t21 light dark cycle |
| topic | sleep circadian rhythms rats memory circadian misalignment |
| url | https://www.frontiersin.org/article/10.3389/fnins.2020.551843/full |
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