Lots of Different Neurons

Scientists have known for years there are two types of brain cells: Neurons and glial cells. But it turns out there are many types of neurons!

Neurons are the cells we usually associate with the brain. They're responsible for memory, conscious and unconscious thought and provide the neural network that allows for communication in the body.

Researchers involved in the study isolated the nucleus of over three thousand individual neurons from six different areas of the cerebral cortex; that's the outermost layer of the brain. The purpose of isolating the nuclei was to group neurons according to which genes were active. The patterns of genes that were active was used to classify the neurons as 16 different subtypes. The subtypes were then found to be clustered into different areas of the brain which possibly means neurons with similar roles are located together.

This mapping of different neurons could pay big dividends in the future. Scientists could compare other neurons to this reference map and learn what a healthy brain is compared to a diseased one. Scientists will be able to ask if certain brain diseases are associated with changes in the genes these neurons are using. It also could explain why these regions of the brain act differently. The answers could lead to new discoveries about neurodegenerative diseases such as Parkinson's and Alzheimer's.

Eventually, scientists hope they may identify all the unique types of neurons in the brain. This study used brain cells from a healthy donor and plans are to obtain cells from other brains in order to isolate more neuronal nuclei and hopefully complete the gene mapping of the brain.