Cannabis binds to the so-called Cannabinoid receptor 1 (CB1-receptor), one of the most common receptors in our brain. CB1-receptors serve as switches that can turn various biological processes on or off. Under normal circumstances, the CB1-receptors are activated by cannabis-like substances that are produced in the brain. For a long time, CB1-receptors were believed to be situated only on nerve cells (neurons), but the team has shown that another player is involved as well: astrocytes.
Astrocytes are a type of glia cell in the brain and spinal cord. These cells play an important supportive role in the nervous system. The team discovered that the CB1-receptors located on these cells play an important role in how the brain develops, especially in one’s earlier years. The researchers specifically looked at a process known as plasticity – which is how the brain adjusts and changes. At younger ages, there are certain periods when the brain has heightened plasticity, meaning that it can adapt and change more easily. This is known as the critical period.