Take an animated look inside the neuron, and learn how scientists are addressing brain disease. With approximately 86 billion neurons in the brain, humans contain the most complex communications network imaginable. To address diseases of brain development and degeneration, neuroscientists are investigating how and why this network breaks down, and what can be done to repair it.

One area of study is dendrites, which are the tree-like structures of neurons, that receive electrical impulses. Researchers are carefully mapping out brain circuits and uncovering how connectivity changes can result in defects of the visual system or behavioral problems. The core section of the neuron is the cell body. Genetic engineering tools are revealing how mutations impact brain development and contribute to autism spectrum disorder or rare, inherited forms of neurological disease.

The transmission of nerve impulses occurs along the axon, which is insulated, much like an electrical wire, by a fatty layer called the myelin sheath. Scientists have invented a medicine to stop the immune system from mistakenly attacking this layer, which occurs during multiple sclerosis. Other molecules currently in development instruct the body to regenerate the sheath and repair damage. The axon also transports valuable cellular cargo, such as neurotransmitters, along tracks from one end of the neuron to the other.

Researchers are testing drug candidates for their ability to remove molecular traffic jams when this transport system fails, as often occurs in Parkinson’s and Alzheimer’s disease. The axon terminals make connections called synapses with other cells, using neurotransmitters as signals. Some scientists are evaluating how finely tuning the receptors for these chemicals could ease depression and anxiety.

Others are finding ways to promote the regrowth of lost synapses, which could halt neurodegeneration. From genetics to behavior, neuroscience is accelerating new interventions for the most challenging disorders of the nervous system.

Learn more: https://www.scripps.edu/