FlashcardsChapter03
Acetylcholine (ACh)
The neurotransmitter responsible for motor control at the junction between nerves and muscles; it is also involved in mental processes such as learning, memory, sleeping, and dreaming. (page 78)
Action potential
The electrical signal that passes along the axon and subsequently causes the release of chemicals from the terminal buttons. (page 72)
All-or-none principle
The principle that when a neuron fires, it fires with the same potency each time; a neuron either fires or not – it cannot partially fire, although the frequency of firing can vary. (page 75)
Amygdala
A brain structure that serves a vital role in learning to associate things with emotional responses and in processing emotional information. (page 86)
Autonomic nervous system (ANS)
A component of the peripheral nervous system; it transmits sensory signals and motor signals between the central nervous system and the body’s glands and internal organs. (page 98)
Axon
A long, narrow outgrowth of a neuron by which information is conducted from the cell body to the terminal buttons. (page 71)
Basal ganglia
A system of subcortical structures that are important for the planning and production of movement. (page 87)
Brain stem
An extension of the spinal cord; it houses structures that control functions associated with survival, such as heart rate, breathing, swallowing, vomiting, urination, and orgasm. (page 84)
Broca’s area
A small portion of the left frontal region of the brain, crucial for the production of language. (page 82)
Cell body
The site in the neuron where information from thousands of other neurons is collected and integrated. (page 71)
Central nervous system (CNS)
The brain and the spinal cord. (page 70)
Cerebellum
A large, convoluted protuberance at the back of the brain stem; it is essential for coordinated movement and balance. (page 84)
Cerebral cortex
The outer layer of brain tissue, which forms the convoluted surface of the brain; the site of all thoughts, perceptions, and complex behaviors. (page 87)
Chromosomes
Structures within the cell body that are made up of DNA, segments of which comprise individual genes. (page 106)
Corpus callosum
A massive bridge of millions of axons that connects the hemispheres and allows information to flow between them. (page 87)
Dendrites
Branchlike extensions of the neuron that detect information from other neurons. (page 71)
Dizygotic twins
Also called fraternal twins; twin siblings that result from two separately fertilized eggs and therefore are no more similar genetically than non-twin siblings. (page 111)
Dominant gene
A gene that is expressed in the offspring whenever it is present. (page 108)
Dopamine
A monoamine neurotransmitter involved in motivation, reward, and motor control over voluntary movement. (page 79)
Electroencephalograph (EEG)
A device that measures electrical activity in the brain. (page 82)
Endocrine system
A communication system that uses hormones to influence thoughts, behaviors, and actions. (page 99)
Endorphins
Neurotransmitters involved in natural pain reduction and reward. (page 80)
Frontal lobes
Regions of the cerebral cortex – at the front of the brain – important for movement and higher-level psychological processes associated with the prefrontal cortex. (page 84)
Functional magnetic resonance imaging (fMRI)
An imaging technique used to examine changes in the activity of the working human brain by measuring changes in the blood’s oxygen levels. (page 84)
GABA
Gamma-aminobutyric acid; the primary inhibitory transmitter in the nervous system. (page 80)
Gene expression
Whether a particular gene is turned on or off. (page 106)