In my 2-Minute Neuroscience videos I explain neuroscience topics in 2 minutes or less. In this video, I discuss the effects of cocaine on the brain. I describe cocaine’s primary mechanism of action, which involves inhibition of the reuptake of monoamine neurotransmitters like dopamine, norepinephrine, and serotonin. I also discuss the mesocorticolimbic dopamine pathway, which connects the ventral tegmental area with the nucleus accumbens, and is activated when someone uses cocaine.
Welcome to 2 minute neuroscience, where I simplistically explain neuroscience topics in 2 minutes or less. In this installment I will discuss the effects of cocaine on the brain.
Cocaine is a strong stimulant that can cause a range of effects including increased energy, alertness and euphoria, along with an elevated heart rate and other sympathetic nervous system responses. Cocaine also has a high potential for abuse and inclines users towards compulsive administration of the drug.
Although all of the details of how cocaine produces its effects are not known, it is thought that the main mechanism by which cocaine acts on the brain is through the inhibition of the reuptake of neurotransmitters called monoamines. Monoamines are a group of neurotransmitters that includes dopamine, norepinephrine, and serotonin. Reuptake is a method of removing neurotransmitters from the synaptic cleft between neurons. When reuptake is inhibited, it causes increased levels of neurotransmitters in the synaptic cleft.
Cocaine inhibits reuptake by blocking the action of the proteins known as transporters that are normally responsible for it. By blocking monoamine transporters and inhibiting monoamine reuptake, cocaine causes levels of dopamine, norepinephrine, and serotonin to increase in the brain, enhancing the activity of these neurotransmitters at their receptors.
Although cocaine increases levels of dopamine, norepinephrine, and serotonin, it is not very clear what the individual contribution of each of these neurotransmitters is to the effects of the drug. However, it is generally thought that cocaine’s action at dopamine receptors is most important for making cocaine rewarding and promoting the compulsive use of the drug. The mesocortical and mesolimbic dopamine pathways, which are sometimes called the mesocorticolimbic dopamine pathway, are pathways that are rich in dopamine neurons; they project from a dopamine rich region in the brainstem called the ventral tegmental area to a variety of locations in the limbic system and frontal cortex. These areas include a region called the nucleus accumbens, which is considered important to addiction and is activated whenever we do something rewarding. Thus, when someone uses cocaine, dopamine activity along the mesocorticolimbic pathway is increased, causing dopamine levels to rise in regions like the nucleus accumbens.