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NOVA: The Cannabis Question

Eaten, dabbed, vaped and smoked – cannabis use is on the rise and our nation is at a crossroads

  • Christina Zeiders

In The Cannabis Question, NOVA explores our relationship with cannabis, uncovers what scientists have discovered about the plant’s effects on the body and brain, and examines the criminalization that has disproportionately targeted communities of color over several decades.

Watch NOVA: The Cannabis Question on-demand through the free PBS Video app or, or on WITF TV Wednesday, April 13 at 9pm. Set a reminder to watch here.

Cannabis is growing into a multi-billion-dollar industry as it moves out of the shadow of the illicit market and into newly legalized mainstream commerce. Nearly 55 million Americans say they currently use it, and yet there’s been surprisingly little scientific investigation of the plant in the United States.

The Cannabis Question follows scientists leading research on the endocannabinoid system—a collection of chemicals and receptors throughout the brain and body that help the body maintain balance, or homeostasis.

In fact, the cannabinoid receptor—named after cannabis—is the most abundant receptor in the brain. These receptors bind with our own cannabis-like molecules to regulate key functions such as appetite, cognition, memory, and emotion. Disruption of this crucial biological system can be associated with psychiatric disorders such as post-traumatic stress disorder (PTSD).

We’ll hear personal stories from people who use it to treat side effects from chemotherapy, PTSD, anxiety, and chronic pain. It follows Stanford neuroscientist Catherine Jacobson who experimented with CBD extracts as a treatment for her son, whose chronic epilepsy was not controlled by pharmaceutical drugs.

Her work helped pave the way for an FDA-approved cannabis-related drugs—Epidiolex—which can be prescribed to treat seizures. The film goes on to document clinical trials currently underway, including research into whether CBD could improve life for children with autism.

Scientists are just beginning to explore questions about the risks recreational use may pose to the developing brain. A clinical study by psychologist Joanna Jacobus scanned over 1,000 teenagers’ brains to examine cognitive differences between those who use cannabis and those who don’t. Researchers at Washington University in St. Louis look into prenatal exposures and how it affects the brain at the earliest stages of development.

The film also looks at the history of criminalization in the U.S. which started in 1937. At the time, government officials tapped into the prejudice towards Mexican immigrants, demonizing the Mexican Spanish word for cannabis – “marijuana” – and claiming it caused violent and deviant sexual acts.

In the 1970s, Richard Nixon ignored an expert panel recommending decriminalization and declared a “war on drugs,” which targeted radical youth, the poor, and especially people of color. Ultimately, the “war on drugs” would cost around a trillion dollars and contribute to a 700% increase in incarceration in under 40 years.

While an enormous number of Americans continue to experience the devastating effects of criminalization, cannabis is thriving in the wellness industry in legalized states—and government regulation is poised to become a major national debate.

Watch NOVA: The Cannabis Question on WITF TV Wednesday, April 13 at 9pm or on-demand through the free PBS Video app or

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