Long term effects of weed
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Long-Term Effects of Cannabis Use
Psychosocial and Educational Impact
Lower Educational Achievement and Psychiatric Illness
Long-term cannabis use, especially at high intake levels, has been linked to several adverse psychosocial outcomes. These include lower educational achievement and, in some cases, psychiatric illnesses such as psychosis . However, the evidence does not clearly establish a cause-and-effect relationship between cannabis use and these psychosocial issues.
Cannabis as a Gateway Drug
There is also a consideration that cannabis may act as a "gateway" drug, potentially leading to the use of more harmful substances like heroin. This gateway hypothesis remains a topic of ongoing research and debate.
Cognitive and Brain Structure Changes
Cognitive Deficits
Chronic cannabis use is associated with small to moderate deficits in various cognitive domains, including executive function, learning and memory, and decision-making. These cognitive impairments persist even after prolonged abstinence, although the magnitude of these deficits is generally small .
Brain Structure Alterations
Research indicates that long-term cannabis use can lead to structural changes in the brain. Regular cannabis users show reduced gray matter volume in regions such as the medial temporal cortex, temporal pole, parahippocampal gyrus, insula, and orbitofrontal cortex . These areas are rich in cannabinoid CB1 receptors and are involved in motivational, emotional, and affective processing. Functional imaging studies also reveal differences in brain activation patterns, particularly in the hippocampal, prefrontal, and cerebellar areas.
Physical Health Risks
Respiratory and Cardiovascular Disorders
Long-term cannabis use has been associated with respiratory issues, particularly in smokers, and cardiovascular disorders . These physical health risks are significant, although cannabis is often considered relatively safe compared to other recreational drugs.
Oculomotor Function
Chronic cannabis use can impair basic visuomotor skills, including increased latency in prosaccade and antisaccade tasks and prolonged saccade amplitudes. These impairments affect visual search, spatial navigation, and reading abilities.
Developmental Concerns
Prenatal and Adolescent Exposure
Exposure to cannabis during prenatal and adolescent stages can have long-lasting effects on mental health and neural systems. This is particularly concerning for vulnerable populations such as pregnant women and adolescents. The interaction between cannabis use and genetic polymorphisms can increase the risk of mental health issues.
Conclusion
The long-term effects of cannabis use are multifaceted, impacting psychosocial outcomes, cognitive function, brain structure, and physical health. While some adverse effects are well-documented, the causal relationships remain complex and require further longitudinal studies for a comprehensive understanding. Despite these risks, cannabis is often perceived as less harmful compared to other illicit substances, highlighting the need for balanced and informed discussions on its use.
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