2-Minute Neuroscience: Parkinson's Disease

In this video, I discuss Parkinson's disease---the second most common neurodegenerative disease behind Alzheimer's disease. Parkinson's disease is associated with the degeneration and death of dopamine neurons in the substantia nigra. The substantia nigra is a region of the brain that is part of a collection of structures known as the basal ganglia, which are important to movement. Parkinson's disease patients experience severe movement difficulties that become more problematic as the degeneration of substantia nigra neurons becomes more extensive. The most common treatment for Parkinson's disease involves the administration of L-DOPA, a precursor to dopamine that allows the brain to synthesize more of the neurotransmitter to replenish depleted dopamine levels.

For an article (on my website) that discusses Parkinson's disease more in depth, click this link: https://neuroscientificallychallenged...

TRANSCRIPT:

Welcome to 2-minute neuroscience, where I explain neuroscience topics in 2 minutes or less. In this installment I will discuss Parkinson’s disease.

Parkinson’s disease is considered a neurodegenerative disease because it involves the degeneration and death of neurons. It is most frequently seen in adults over the age of 50.

The most recognizable symptoms of Parkinson’s initially are movement-related and generally involve a tremor that is worse when a person is at rest, bradykinesia, which is slowness of movement, rigidity, and postural impairment. Parkinson’s patients also often experience non-motor symptoms like cognitive impairment or psychiatric symptoms. The causes of Parkinson’s are not fully understood, but a combination of genetic and environmental factors is likely involved.

Parkinson’s patients have low levels of the neurotransmitter dopamine in the basal ganglia, a group of structures involved with movement (among other functions). These low dopamine levels in the basal ganglia are caused by the death of dopamine neurons in a region of the basal ganglia called the substantia nigra. The substantia nigra has high numbers of dopamine neurons, but by the end stages of Parkinson’s patients have often lost more than half of the dopamine neurons in this region.

The most common treatment for Parkinson’s involves an attempt to restore depleted dopamine levels in the basal ganglia. Because dopamine does not cross the blood-brain barrier, dopamine cannot simply be administered to a patient. Instead, however, patients can be given a precursor to dopamine called L-DOPA. L-DOPA can cross the blood-brain barrier and is used by the brain to synthesize more dopamine. This can lead to improvement in the motor symptoms of Parkinson’s, but L-DOPA does not halt the neurodegeneration that occurs in parkinson’s disease, and long-term use of L-DOPA can cause a number of side effects, including movement-related problems. So it is not a cure for the disease and other treatments are still being explored.

REFERENCE:

Purves D, Augustine GJ, Fitzpatrick D, Hall WC, Lamantia AS, McNamara JO, White LE. Neuroscience. 4th ed. Sunderland, MA. Sinauer Associates; 2008.