Glossary

brain stem: all information to and from the rest of the body passes through the brain stem, which controls breathing and heartbeat and plays a vital role in attention and arousal.

cerebellum: the region involved with coordinating complex voluntary muscular movement, balance, and posture.

cognitive: related to conscious intellectual activity, such as reasoning, imagining, or memorizing.

cortex: thin outer layer of the brain that helps mammals process sensory information and make decisions. In humans, an expanded cortex makes complex thought and reasoning possible.

electrochemical: involving both electrical and chemical processes. In the brain, neurons communicate across synapses when chemical signals called neurotransmitters trigger reactions in the cell that change the electrical properties of the next cell.

limbic system: a set of brain structures present in mammals that help generate emotional responses, motivations, and memory, particularly ones related to survival.

nervous system: a branching network of neurons that sends, receives, and processes nerve signals throughout the body. Organs and muscles rely upon these impulses to function.

neurons: key building blocks of the nervous system responsible for processing and transmitting electrical and chemical information. These cells have long, slender extensions that can connect to other neurons or muscle and gland cells.

neurotransmitters: chemicals released by a neuron to transmit signals across a synapse to another cell.

plasticity: the ability of the brain to change in response to experience by forming new neuronal connections. This allows it to learn and compensate for injury or disease.

prefrontal cortex: the front of the cortex, responsible for complex cognitive behaviors, including mediating conflicting thoughts, evaluating decisions, and predicting future events.

synapse: connection point where one neuron communicates with another.

vertebrate: any member of the large group of animals that possess a backbone or spinal column, such as lizards, mammals, birds, and fish.