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Published on: July 12, 2021
Melatonin suppresses nighttime memory formation in zebrafish
Oliver Rawashdeh1, Nancy Hernandez de Borsetti, Gregg Roman
1Department of Biology and Biochemistry, University of Houston, 369 Science and Research II, Houston, TX 77204-5001, USA.
Science (New York, N.Y.)
|November 17, 2007
Summary
The biological clock affects memory. In zebrafish, melatonin suppresses memory formation at night, but blocking melatonin improves nighttime memory.
Area of Science:
- Chronobiology
- Neuroscience
- Behavioral Science
Background:
- Biological clock mechanisms influencing memory remain largely unknown.
- Diurnal rhythms significantly impact cognitive functions, including learning and memory.
Purpose of the Study:
- To investigate the role of the biological clock and melatonin in regulating memory formation.
- To elucidate the specific mechanisms by which melatonin affects learning and memory in zebrafish.
Main Methods:
- Operant conditioning paradigm in diurnal zebrafish.
- Administration of melatonin during daytime and melatonin receptor antagonists at nighttime.
- Pinealectomy and training under constant light conditions.
Main Results:
- Learning and memory were significantly better during the day compared to the night.
- Daytime melatonin treatment mimicked nighttime memory suppression.
- Constant light exposure improved nighttime memory by reducing melatonin levels.
- Melatonin receptor antagonist treatment and pinealectomy enhanced nighttime memory formation.
Conclusions:
- Melatonin is both sufficient and necessary for impaired memory formation during the night.
- These findings highlight melatonin as a key regulator of circadian influences on memory.
