Why Does Weed Make Some People Giggle and Some People Freak Out?

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It has long been observed that marijuana — or cannabis, weed, grass, or pot, as you prefer — can produce seemingly contradictory psychological effects in the people who smoke (or, these days, vape or nibble) it. Some partakers experience a feeling of elation; others descend into paranoid anxiety.

A study of the effects of THC (tetrahydrocannibinol), the main psychoactive ingredient in marijuana, conducted at Western University in Ontario, Canada, has discovered why this happens.

Since medical marijuana is now legal in 33 states and recreational weed is legal in 11 and Washington D.C., it seems appropriate that scientists would want to analyze exactly how THC works.

Studying the behavior of rats fed the chemical, using “an integrative combination of behavioral pharmacology and…electrophysiology,” the Canadian researchers discovered that reactions to marijuana depend on which part of an individual brain is the most sensitive to THC. 

While they haven’t yet identified the molecular pathways that lead to one part or the other, they observed that if the anterior (front) part of the brain is most sensitive, the drug’s effect is one of happiness and relaxation. If it’s the posterior (rear) portion, fear and paranoia are likely to set in. 

Exactly why it affects different parts of the brain in different subjects isn’t yet understood. Relaxation is obviously preferable to fear as a reaction, though. Stress and other things can lead to memory loss and brain shrinkage.

Human studies are next. A co-author of the study, Western University professor Steven R. Laviolette, told Yahoo Lifestyle that the eventual goal of this research is to be able to modulate THC formulations so that they don’t activate negative feelings. Such information would be invaluable to North America’s largest marijuana companies.