Speaker 1: Hey, this is Julie Douglas from the podcast The Stuff
Speaker 1: of Life here to tell you that super producer Noel
Speaker 1: Brown and I are cooking up season two for an
Speaker 1: August release. So if you haven't already checked out season
Speaker 1: one of the Stuff of Life, there's a big bowl
Speaker 1: of ten episodes ready for you to dig into on
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Speaker 1: In the meantime, apply sunscreened liberally and we'll see you
Speaker 1: in August. Welcome to brain Stuff from How Stuff Works. Hey,
Speaker 1: brain Stuff, this is Christian Seger. So here in the
Speaker 1: United States, marijuana is most commonly used as an illicit drug.
Speaker 1: Our society thinks of stereotypical users as being you know,
Speaker 1: forgetful and absent minded. And this is because the main
Speaker 1: psychoactive ingredient in marijuana impairs our memory. It's called tetro
Speaker 1: hydro cannabinal or for the sake of you know, brevity,
Speaker 1: th HC. Th HC alters how information is processed in
Speaker 1: the hippocampus. This is the area of the brain that
Speaker 1: is responsible for memory formation. However, you consume marijuana, THHC
Speaker 1: enters your brain by latching onto a protein called cannabinoid
Speaker 1: receptor type one, or c B one for short. There
Speaker 1: are c B one sprinkled throughout the brain. There in
Speaker 1: your cortex, basil, ganglia, the hypothalamus, and the hippocampus where
Speaker 1: we form our memories. See where I'm going here for
Speaker 1: a short term memory. Forty years worth of different studies
Speaker 1: show that th HC disrupts our short term memory, making
Speaker 1: it hard to form new memories when you're high. This
Speaker 1: also makes it really difficult to remember what happened when
Speaker 1: you were high, even after the th HC wears off,
Speaker 1: and larger doses of th HC have even more of
Speaker 1: an effect on memory. Frequent users are more tolerant to
Speaker 1: the th HC, however, and its effects including memory loss.
Speaker 1: But what about recalling your existing memories. Th HC does
Speaker 1: not actually affect that, nor does it lead to memory
Speaker 1: loss or dementia. Therefore, users can remember things they already know,
Speaker 1: like their name or where they live. And Our bodies
Speaker 1: have a biological system made of natural marijuana like compounds.
Speaker 1: This is called the endocannabinoid system. It regulates our memory formation,
Speaker 1: functioning as a filter so we're not overloaded with information.
Speaker 1: The system is involved in the extinction of our negative
Speaker 1: memories as well. That's what they call it extinction. It
Speaker 1: can influence pain, memory, mood, and even appetite, and researchers
Speaker 1: hope that by using THHC they can help people forget
Speaker 1: bad memories such as post traumatic stress disorder. So studies
Speaker 1: do show that as people age, they lose neurons in
Speaker 1: the hippocampus, and chronic THC use can hasten this loss. Also,
Speaker 1: a study out of Northwestern University published in March of
Speaker 1: fifteen showed that teens who smoked daily for three or
Speaker 1: more years have been found to have an abnormally shaped hippocampus.
Speaker 1: They also performed poorly on long term memory tests, eighteen
Speaker 1: percent worse than those who didn't use marijuana. The deformation
Speaker 1: of the hippocampus is thought to be connected to this
Speaker 1: poor memory. Subjects in this study took a narrative memory
Speaker 1: test where they listened to a series of stories for
Speaker 1: one minute twenty to thirty minutes later, they were asked
Speaker 1: to recall as much from the stories as they could,
Speaker 1: and this assessed their ability to encode, store, and recall
Speaker 1: details from their stories. The longer the individuals used marijuana chronically,
Speaker 1: the more abnormal their hippocampus was shaped. This probably damages
Speaker 1: its neurons and its axons, as well as supportive environments.
Speaker 1: The abnormalities didn't seem to go away either, even when
Speaker 1: observed in individuals in their early twenties who had stopped
Speaker 1: using marijuana for over two years now. It's important to
Speaker 1: note that drawing definitive conclusions about marijuana's long term effects
Speaker 1: is difficult because steady participants often use multiple substances. Rats
Speaker 1: exposed to th HC before they're born, after birth, and
Speaker 1: during rat adolescence show problems with learning and memory tasks
Speaker 1: later in their lives. A rats hippocampus changes as well
Speaker 1: when it's exposed to th HC, and imaging in human
Speaker 1: adolescence shows that regular users display impaired neural connectivity. This
Speaker 1: affects memory, learning, and impulse control. The endocannabinoid system is
Speaker 1: important to the formation of our synapses during early brain
Speaker 1: development and refining them during adolescence, so it's possible that
Speaker 1: marijuana use is affecting this development. If you want to
Speaker 1: learn more about marijuana, memory, and medical health, I recommend
Speaker 1: that you go check out my other podcasts stuff to
Speaker 1: blow your mind. We just recently did two deep dive
Speaker 1: episodes into marijuana. Check it out. Check out the brain
Speaker 1: Stuff channel on YouTube, and for more on this and
Speaker 1: thousands of other topics, visit how stuff works dot com