Neuroscience

Neurons, action potentials, synaptic plasticity, and the Hodgkin-Huxley model

What is neuroscience?

Neuroscience is the study of the nervous system — the brain, spinal cord, and the network of nerves that together control behavior, process sensory information, and generate thought, memory, and emotion.

Neurons: the basic unit of the nervous system

The nervous system is built from specialized cells called neurons, each capable of receiving, processing, and transmitting electrical and chemical signals. A neuron has branching extensions called dendrites that receive incoming signals, a cell body that processes them, and a long fiber called an axon that carries an outgoing signal onward to the next neuron or target cell. Neurons connect to each other at junctions called synapses, where the signal passes from one neuron to the next.

How neurons communicate

A neuron transmits information using a combination of electrical and chemical signals. An electrical signal travels rapidly down the neuron's axon; when it reaches the synapse, it triggers the release of chemical messengers called neurotransmitters, which cross the tiny gap to the next neuron and either encourage or discourage that neuron from firing its own signal in turn.

The brain's major regions

The human brain is organized into several major regions, each specialized for different functions. The cerebrum, the largest part, handles higher functions like thought, voluntary movement, and sensory processing, further divided into specialized regions for vision, hearing, movement, and more. The cerebellum coordinates balance and fine motor control. The brainstem controls basic, automatic life functions like breathing and heart rate.

Why neuroscience matters

Neuroscience underlies the understanding and treatment of neurological and psychiatric conditions, informs how we understand learning, memory, and behavior, and increasingly guides the development of technologies like brain-computer interfaces and treatments for conditions affecting the nervous system.