Most people assume that use of marijuana would cause a progression in memory loss, but new studies show it might actually improve the brain and memory in older adults and help to reduce progressive memory loss.
Nearly 40-60% of those over age 65 experience progressive memory loss. The hippocampus, a region of the brain involved in the formation and retrieval of memories, often deteriorates with age. Hormones and proteins that protect and repair brain cells and stimulate neural growth also decline with age. Additionally, older people often experience decreased blood flow to the brain, which can impair memory and lead to changes in cognitive skills.
Cannabis might be able to help with all these factors. A recent study published in the journal Nature Medicine revealed that older mice reverted back to the state of 2-month old mice after being administered low-dose cannabis treatment.
The homeostatic mechanisms in the endocannabinoid system (ECS) largely determine the progression of aging. ECS activity declines during aging because CB1 receptor expression and coupling to G proteins is reduced, and levels of the major endocannabinoid 2-arachidonoylglycerol (2-AG) decrease
In the study, a low dose of Δ9-tetrahydrocannabinol (THC) reversed the age-related decline in cognitive performance of aged mice. The study found an enhanced expression of synaptic marker proteins and increased hippocampal spine density. Additionally, THC treatment restored hippocampal gene transcription patterns to those of THC-free animals aged 2 months.
THC improves cerebral blood flow. Cannabinoids perform essential functions within the brain, and as one ages, the number of cannabinoids produced in the brain decrease. As the cannabinoid system declines, the brain further accelerates aging.
Nature Medicine volume 23, pages 782–787 (2017)