Chapter 3 Flashcards
neurons
cells in the nervous system that communicate with each other to perform information-processing tasks
cell body (soma)
largest component of the neuron that coordinates the information-processing tasks and keeps the cell alive
dendrite
receive information from other neurons and relay it to the cell body
axon
carries information to other neurons, muscles, or glands
myelin sheath
an insulating layer of fatty material
glial cells
support cells found in the nervous system
synapse
junction or region between the axon of one neuron and the dendrites or cell body of another
sensory neurons
receive information from the external world and convey this information to the brain via the spinal cord
motor neurons
carry signals from the spinal cord to the muscles to produce movement
interneurons
connect sensory-, motor-, or other inter-neurons
resting potential
the difference in electric charge between the inside and outside of a neuron’s cell membrane
action potential
an electric signal that is conducted along the length of a neuron’s axon to a synapse
refractory period
the time following an action potential during which a new action potential cannot be initiated
terminal buttons
knoblike structures at the end of an axon
neurotransmitters
chemicals that transmit information across the synapse to a receiving neuron’s dendrites
receptors
parts of the cell membrane that receive neurotransmitters and either initiate or prevent a new electric signal
Acetylcholine (ACh)
a neurotransmitter involved in a number of functions, including voluntary motor control
dopamine
a neurotransmitter that regulates motor behaviour, motivation, pleasure, and emotional arousal
glutamate
major excitatory neurotransmitter in the brain
GABA (gamma-aminobutyric acid)
primary inhibitory neurotransmitter in the brain
norepinephrine
involved in states of vigilance, or a heightened awareness of dangers in the environment
serotonin
involved in the regulation of sleep and wakefulness, eating, and aggressive behaviour
endorphins
chemicals that act within the pain pathways and emotion centres of the brain (endogenous morphine)
agonists
drugs that increase the action of a neurotransmitter
antagonists
drugs that diminish the function of a neurotransmitter
nervous system
an interacting network of neurons that conveys electrochemical information throughout the body
central nervous system (CNS)
composed of the brain and spinal cord
peripheral nervous system (PNS)
connects the central nervous system to the body’s organs and muscles
somatic nervous system
a set of nerves that conveys information between voluntary muscles and the central nervous system
autonomic nervous system (ANS)
a set of nerves that carries involuntary and automatic commands that control blood vessels, body organs, and glands
sympathetic nervous system
a set of nerves that prepares the body for action in challenging or threatening situations
parasympathetic nervous system
helps the body return to a normal resting state
spinal reflexes
simple pathways in the nervous system that rapidly generate muscle contractions
reflex arc
a neural pathway that controls reflex actions
hindbrain
an area of the brain that coordinates information coming into and out of the spinal cord
medulla
an extension of the spinal cord into the skull that coordinates heart rate, circulation, and respiration
reticular formation
regulates sleep, wakefulness, and levels of arousal
cerebellum
a large structure of the hindbrain that controls fine motor skills
pons
a structure that relays information from the cerebellum to the rest of the brain
tectum
orients an organism in the environment using senses
tegmentum
involved in movement and arousal
cerebral cortex
the outermost layer of the brain, visible to the naked eye, and divided into two hemispheres
subcortical structures
areas of the forebrain housed under the cerebral cortex near the centre of the brain
thalamus
relays and filters information from the senses and transmits the information to the cerebral cortex
hypothalamus
regulates body temperature, hunger, thirst, and sexual behaviour
hippocampus
critical for creating new memories and intergrating them into a network of knowledge so that they can be stored indefinitely in other parts of the cerebral cortex
amygdala
located at the tip of each horn of the hippocampus, ,plays a central role in many emotional processes, particularly the formation of emotional memories
basal ganglia
a set of subcortical structures that directs intentional movements
endocrine system
a network of glands that produce and secrete into the bloodstream chemical messages known as hormones, which influence a wide variety of basic functions, including metabolism, growth, and sexual development
pituitary gland
“master gland” of the body’s hormone-producing system, which releases hormones that direct the functions of many other glands in the body
corpus callosum
connects large areas of the cerebral cortex on each side of the brain and supports communication of information across the hemisphere
occipital lobe
processes visual information
parietal lobe
located in front of the occipital lobe, it carries out functions that process information about touch
temporal lobe
located on the lower side of each hemisphere, it is responsible for hearing and language
frontal lobe
sits behind the forebrain, has specialized areas for movement, abstract thinking, planning, memory, and judgement
association areas
composed of neurons that help provide sense and meaning to information registered in the cortex
mirror neurons
active when an animal performs a behaviour, such as reaching for or manipulating an object, and are also activated when another animal observes that animal performing the same behaviour
gene
major unit of hereditary transmission
chromosomes
strands of DNA wound around each other in a double-helix configuration
epigenetics
study of environmental influences that determine whether or not genes are expressed, or the degree to which they are expressed, without altering the basic DNA sequences that constitute the genes themselves
epigenetic marks
chemical modifications to DNA that can turn genes on or off
DNA methylation
adding a methyl group to DNA
histone modification
adding chemical modifications to proteins called histones that are involved in packaging DNA
heritability
a measure of the variability of behavioural traits among individuals that can be accounted for by genetic factors
electroencephalograph (EEG)
a device used to record electrical activity in the brain
