Science feature

This is your brain on cannabis

MIT alumnus gives $4.5M to support research into the effects of cannabis on the brain

The MIT School of Science announced on Tuesday that Charles Broderick ’99 has made a $9 million gift to MIT and Harvard Medical School to support basic science research into the effects of cannabis on the brain and human behavior through the creation of the Broderick Fund for Phytocannabinoid Research. With the legalization of marijuana becoming increasingly prevalent (11 states, including Massachusetts, have fully legalized marijuana, and 23 additional states have legalized medical marijuana), both the scientific and the medical communities have voiced concerns on the lack of research of the neurological phenomena that underlie the effects of marijuana use in adults and adolescents. Broderick, who has worked closely with marijuana companies since leaving MIT as a private investor and founder of Uji Capital LLC, created the fund in an effort to destigmatize cannabis use by increasing both the public and the medical community’s understanding of the science behind cannabis.

MIT has received half of the $9 million gift, and that $4.5 million will be used to support four researchers at the McGovern and Picower Institutes: Earl Miller, Myriam Heiman, Ann Graybiel, and John Gabrieli. This gift aims to make strides in that area over the next three years by supporting both basic science and clinical research into the neurological effects of cannabis. The Tech spoke with Miller, Heiman, and Gabrieli about their plans.

The Heiman Lab focuses on uncovering the molecular phenomena that lead to neurodevelopmental and neurodegenerative disease. Myriam Heiman, Latham Family associate professor of neuroscience at the Picower Institute, plans to use the funds to explore the relationship between cannabis and neurological disorders, specifically schizophrenia and Huntington’s Disease. Her work in schizophrenia relates to the glutamate hypothesis, which suggests that dysfunctions in the glutamatergic signaling pathway contribute to the development of schizophrenia. Cannabis is thought to restore this pathway via the cannabinoid receptor, which reduces production of glutamate, a neurotransmitter that excites other neurons and is linked to many psychiatric disorders. However, long-term cannabis use in adolescents is linked to the development of schizophrenia for reasons that are not currently well understood. Heiman believes that developing a better understanding of the role of the cannabinoid receptor in this signaling pathway might uncover drug targets or therapeutic options that were not previously known, saying, “Often if you look at what is broken in a system, you can find out how the system works.”

The Gabrieli Laboratory explores the neural circuit systems involved in emotion and learning through functional MRI (fMRI) and behavioral studies. John Gabrieli, professor of brain and cognitive sciences and health sciences and technology at the McGovern Institute, is interested in focusing on the role of tetrahydrocannabinol (THC) in cognition. THC is one of the main psychoactive components of cannabis, giving users their characteristic “high.” “There’s some evidence that THC can promote cognition in patients with schizophrenia,” said Gabrieli. He plans to use the gifted funds to perform behavioral and fMRI studies on the effects of THC in adult patients with schizophrenia, in an effort to better understand the mechanisms that underlie this phenomenon. He is also interested in the potential use of cannabis to reduce anxiety in children with autism spectrum disorder, but plans to focus his initial work with the Broderick Fund on understanding the effects of cannabis on neural circuit dynamics in adults.

The Miller Lab studies the neural basis of cognition, focusing on how we focus our attention, hold ideas in our minds, and make decisions. Earl Miller, professor of neuroscience in the Picower Institute, explained his lab’s work as striving to understand “network dynamics, how neurons work together in networks, and how these network properties produce cognition.” The lab previously discovered that there are two types of brain waves involved in top-down and bottom-up processes — that is, processes where we act on our previous knowledge of the world and processes where we act on sensory information. According to Miller, the balance of these two types of brain waves is important for normal cognition: “You can’t have a brain where the floodgates are open and everything is coming right in. You have to have a brain where you can regulate what is important to pay attention to.” Miller’s interest in cannabis relates to these processes and the brain waves that seem to regulate them. “There’s a lot of brain disorders, like attention deficit disorder, where this balance goes awry, so the first thing we want to know is the effect that cannabis has on the balance between top-down and bottom-up brain waves. No one has asked the question at that level yet.” Specifically, he is interested in understanding how cannabinoid receptors, which are involved in appetite, pain, mood, and memory via the aforementioned excitatory glutamate pathway affect neural circuit dynamics that influence these brain waves.  

Looking towards the future, all of the researchers hope to uncover some of the basic mechanisms, on a molecular or systems level, that drive our experiences with cannabis. This knowledge has the potential to both help scientists better understand cognitive functions at the molecular and neural circuit levels and help clinicians design better treatments for neurological diseases. In speaking to MIT News on the topic, Broderick outlined similar hopes for his gift, stating that “We need to replace rhetoric with research” in national conversations around cannabis legislation and use.