From: hubermanlab
Cannabis, also known as marijuana, is a plant that contains over 70 psychoactive compounds, with THC (tetrahydrocannabinol) and CBD (cannabidiol) being the most well-known. These compounds have diverse effects on both the brain and body. Understanding these effects is critical for evaluating the benefits and risks of cannabis use.
Cannabinoids and Their Mechanisms
Cannabis interacts with the body primarily through cannabinoid receptors, which are part of the endocannabinoid system that regulates various physiological processes. The two main cannabinoid receptors are CB1 and CB2. CB1 receptors are concentrated in the brain and play a significant role in modulating neurotransmitter release, while CB2 receptors are linked with the immune system [00:50:00].
- THC is the compound responsible for the ‘high’ associated with cannabis. It binds to CB1 receptors, affecting regions of the brain involved in memory, pleasure, and time perception [00:34:00].
- CBD, on the other hand, does not produce a high and is generally associated with relaxation and potential therapeutic benefits without significant psychoactive effects [00:17:00].
Psychoactive Effects
Mood and Perception
The effects of cannabis on mood and perception can vary significantly:
- Euphoria and Relaxation: Sativa strains generally lead to increased focus, mood elevation, and talkativeness by stimulating the prefrontal cortex and modulating limbic circuits [00:58:00].
- Relaxation and Sedation: Indica strains typically produce relaxation and sedation by affecting CB1 receptors in different neural pathways [01:06:00].
Memory and Cognition
Cannabis affects memory, particularly short-term memory, by impacting hippocampal function. Both sativa and indica can lead to short-term memory impairment [01:10:00].
Speech and Movement
Chronic cannabis use can alter speech patterns, reducing vocal intensity and changing timing, likely due to its effects on motor circuits involved in speech production role of neural circuits [01:39:00].
Physiological Effects
Appetite and Metabolism
Cannabis can increase appetite (the “munchies”) by acting on the hypothalamus, which regulates hunger and energy balance. It affects both cognitive desire for food and digestive tract signaling [01:12:00].
Hormonal Effects
Regular cannabis use has been shown to:
- Increase prolactin levels, thus reducing dopamine and testosterone, which can affect libido and sexual function role_of_testosterone_and_estrogen_in_mens_and_womens_health [01:58:00].
- Impact reproductive hormones by reducing gonadotropin-releasing hormone, potentially affecting fertility impact_of_lifestyle_factors_on_fertility [02:05:00].
Long-term Effects and Risks
Dependence and Tolerance
Chronic cannabis use can lead to tolerance, dependence, and increased anxiety and depression over time. The neurochemical pathways adapt by downregulating receptor sensitivity, requiring more cannabis for the same effect, which may worsen these conditions in the long term [02:21:00].
Impact on Adolescents and Brain Development
Cannabis use in adolescents (ages 16-24) carries significant risks, including:
- Enhanced predisposition to anxiety, depression, and psychosis later in life.
- Accelerated thinning of gray matter in the prefrontal cortex, impairing cognitive functions such as decision-making and planning impact_of_neuroplasticity_on_behavior_and_addiction [02:28:00].
Pregnancy and Fetal Development
The use of cannabis during pregnancy is alarming, given that 15% of pregnant women report using cannabis. Cannabinoids affect fetal brain development critically by interacting with CB1 receptors, which are vital for neural development sensitive_periods_for_neurodevelopment_especially_during_puberty [02:14:00].
Conclusion
While cannabis has evident therapeutic potentials in a controlled setting, such as pain relief and treatment for certain medical conditions, it also poses substantial risks, especially when used chronically or during critical periods of brain development. It is vital for users and healthcare providers to consider these effects when evaluating cannabis use cannabis_effects_on_stress_feeding_and_development.