Breckenridge, CO. Online Offers. Established in 1859, the historic town of Breckenridge is a home rule municipality that is the county seat of Summit County, Colorado, United States. As of the 2010 Census, the town had a population of 4,540. The town also has many part-time residents, as many people have vacation homes in the area. Breckenridge is also a popular ski resort during the winter months, servicing multi-difficulty ski slopes on the Rocky Mountains.
substantia nigra - a layer of deeply pigmented grey matter in the midbrain; associated with the striate body; is involved in metabolic disturbances associated with Parkinson's disease and with Huntington's disease. locus niger, nucleus niger. neural structure - a structure that is part of the nervous system.
...the shape of the lens and the diameter of the pupil. In addition, between the midbrain reticular formation (known here as the tegmentum) and the crus cerebri is a large pigmented nucleus called the substantia nigra. The substantia nigra consists of two parts, the pars reticulata and the pars compacta.