2-Minute Neuroscience: Substantia Nigra скачать в хорошем качестве

2-Minute Neuroscience: Substantia Nigra

In this video I discuss the substantia nigra. I describe the two regions that make up the substantia nigra: the substantia nigra pars compacta and the substantia nigra pars reticulata. I discuss the role of the substantia nigra pars compacta in dopamine production and its contribution to the nigrostriatal pathway, one of the major dopamine pathways in the brain. I also briefly cover the role of the substantia nigra in movement and how this is disrupted by the neurodegeneration that occurs in Parkinson’s disease. For an article (on my website) that explains the substantia nigra, click this link: https://neuroscientificallychallenged... TRANSCRIPT: Welcome to 2 minute neuroscience, where I simplistically explain neuroscience topics in 2 minutes or less. In this installment I will discuss the substantia nigra. The substantia nigra is a structure found in the brainstem that looks like a dark streak in unstained brain tissue. Its appearance is where it gets its name, as substantia nigra is Latin for “black substance.” There are two substantiae nigrae, one on each side of the midline of the midbrain. The substantia nigra is actually made up of two distinct regions: the substantia nigra pars compacta and the substantia nigra pars reticulata. The substantia nigra gets its dark coloring from the large number of dopamine neurons in the substantia nigra pars compacta, as they express high levels of a dark pigment called neuromelanin. In fact, most of the dopamine-producing neurons of the brain are found in either the substantia nigra or an adjacent area called the ventral tegmental area. The dopamine neurons in the substantia nigra are primarily found in the substantia nigra pars compacta, as the substantia nigra pars reticulata is more heavily populated with GABA neurons. The substantia nigra is considered part of the basal ganglia, and many of the dopamine neurons in the substantia nigra pars compacta project to two other structures of the basal ganglia, the caudate and putamen (which together are referred to as the striatum). These dopamine neurons make up a large bundle of fibers called the nigrostriatal pathway. The nigrostriatal pathway is one of the major dopamine pathways in the brain, and is thought to be extremely important in the facilitation of movement. The GABA neurons of the substantia nigra pars reticulata also play important roles in movement, and thus movement is one of the main functions of the substantia nigra. The substantia nigra also has many functions beyond motor control, however the role for the substantia nigra in movement is particularly emphasized when we observe the symptoms of Parkinson’s disease, a neurodegenerative disorder that involves the death of dopamine neurons in the substantia nigra. Individuals suffering from Parkinson’s disease display severe movement-related deficits. Reference: Wichmann T, DeLong MR. 2000. The Basal Ganglia. In: Kandel ER, Schwartz JH, Jessell TM, eds. Principles of Neural Science, 5th ed. New York: McGraw-Hill.