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VANCOUVER, BRITISH COLUMBIA: July 8th, 2010 - An unidentified young man smokes a joint on the steps of the Vancouver Art Gallery on July 8th, 2010. Gallery employees are worried that marijuana smoke is getting into the museum via air vents.



Everyone knows that pot makes you paranoid. Now we know why.

Smoking a joint fires up receptors in part of the amygdala - the brain region that directs our inner horror show, a study has found.

Scientists at the University of Western Ontario in London believe these "cannabinoid" receptors are activated by THC, the main psychoactive component of marijuana, Time reports.

When researchers blocked the receptors in rats, the critters given electric shocks did not learn to associate the jolts with the almond or peppermint scent in their cages, or the striped or polka-dot decor. (If you've already smoked up today, chances are I'm losing you here.)

But rats who got a marijuana-like drug to boost the receptors froze with panic after they were given an electric shock and put back in their (admittedly scary-looking) scented cages.

Pot enhances a kind of fear-based learning about associations, researchers concluded. That leads to paranoia, which means freaking out about things that wouldn't normally trigger anxiety, like a helicopter flying over your 'hood.

The study, published in the Journal of Neuroscience, suggests that marijuana encourages the brain to jump to scary conclusions about places and events, and see patterns and connections that don't really exist (i.e. conspiracy theories).

For example, it's unlikely that helicopter over your house is full of cops out to get you - unless you've got a grow-op in your basement.

What do you think? Does research like this convince you to stop toking? Or will you be romancing Mary Jane as long as you can hold a lighter to a spliff?

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