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Biphasic effects of THC in memory and cognition
Edward J Calabrese1, Alberto Rubio-Casillas2
1Department of Environmental Health Sciences, University of Massachusetts, Amherst, MA, USA.
European Journal of Clinical Investigation
|March 26, 2018
Summary
Delta-9-tetrahydrocannabinol (THC) from cannabis can impair memory but also enhance neurological function in aging animals. This study explains this paradox using hormesis, a biphasic dose-response model.
Area of Science:
- Neuroscience
- Pharmacology
- Aging Research
Background:
- Delta-9-tetrahydrocannabinol (THC), the main psychoactive compound in cannabis, is known to cause short-term memory impairment.
- Recent research suggests THC may improve neurological function and cognitive abilities in aged animals, challenging the established paradigm.
- Studies indicate THC can promote neurogenesis, protect against neurodegeneration in Alzheimer's models, and mitigate inflammation-induced cognitive deficits.
Purpose of the Study:
- To reconcile the seemingly contradictory effects of THC on cognitive function.
- To propose a unifying framework explaining how THC can both impair and improve memory and neurological function.
Main Methods:
- Review and synthesis of existing scientific literature on THC's effects on cognition and neurobiology.
- Application of the hormesis theory (biphasic dose-response) to explain observed THC effects.
Main Results:
- The paradoxical effects of THC, including memory impairment at high doses and cognitive enhancement at low chronic doses, align with hormesis.
- Hormesis provides a framework to understand THC's neuroprotective and memory-restoring properties in aged and diseased models.
Conclusions:
- The observed effects of THC on cognitive function are best explained by a biphasic dose-response relationship, consistent with hormesis.
- Low-dose, chronic THC administration may offer therapeutic potential for age-related cognitive decline and neurodegenerative diseases.
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