Chapter 2 Key Terms Flashcards
Neuron
A specialized cell of the nervous system that receives and transmits messages.
Glial cells
Cells that remove dead neurons and waste products from the nervous system, nourish and insulate neurons, form myelin, and play a role in neural transmission of messages.
Dendrites
Root-like structures, attached to the cell body of a neuron, that receive impulses, or incoming messages, from other neurons.
Axon
A long, thin part of a neuron that transmits impulses to other neurons from bulb-shaped structures called axon terminals or terminal buttons.
Myelin
A fatty substance that insulates axons, facilitating transmission of neural impulses.
Action potential
The electrical impulse that provides the basis for the conduction of a neural impulse along an axon of a neuron
Synapse
A junction between the axon terminals of one neuron and the dendrites or cell body of another neuron.
Neurotransmitters
Chemical substances involved in the transmission of neural impulses from one neuron to another.
Receptor site
A location on a dendrite of a receiving neuron tailored to receive a neurotransmitter.
Dopamine
A neurotransmitter that affects the ability to perceive pleasure, voluntary movement, and learning and memory; it is involved in Parkinson’s disease and appears to play a role ion schizophrenia.
Serotonin
A neurotransmitter involved on emotional arousal ans sleep; deficiencies of serotonin have been linked to eating disorders, alcoholism, depression, aggression, and insomnia.
Central nervous system
The brain and spinal cord.
Peripheral nervous system
The part of the nervous system consisting of the somatic nervous system and the autonomic nervous system.
Somatic nervous system
The division of the peripheral nervous system that connects he central nervous system with sensory receptors, skeletal muscles, and the surface of the body.
Autonomic nervous system (ANS)
The division of the peripheral nervous system that regulates glands and activities such as heartbeat, respiration, digestion, and dilation of the pupils.
Sympathetic division
The branch of the ANS that is most active during emotional responses, such as fear and anxiety, that spend the body’s reserve of energy.
Parasympathetic division
The branch of the ANS that is most active during processes (such as digestion) that restore the body’s reserve of energy.
Spinal cord
A column of nerves within the spine that transmits messages from sensory receptors to the brain and from the brain to the muscles and glands throughout the body.
Electroencephalograph (EEG)
A method of detecting brain waves by means of measuring the current between electrodes placed on the scalp.
Computerized axial tomography (CAT or CT scan)
A method of brain imaging that passes a narrow X-ray beam through the head and measures the structures that reflect the beams from various angles, enabling a computer to generate a three-dimensional image.
Magnetic resonance imaging (MRI)
An imaging method that places a person in a magnetic field and uses radio waves to cause the brain to emit signals that reveal shifts in the flow of blood, which, when the brain is being scanned, indicate brain activity.
Functional MRI (fMRI)
A form of MRI that enables researchers to observe the brain “while it works” by taking repeated scans.
Cerebral cortex
The wrinkled surface area (grey matter) of the cerebrum.
Corpus callosum
A thick fiber bundle that connects the hemispheres of the cortex.
