Psychology from Inquiry to Understanding – Chapter 3 Terms

neuron
Nerve cell specialized for communication

dendrite
Portion of neuron that receives signals

axon
Portion of neuron that sends signals

synaptic vesicle
Spherical sac containing neurotransmitters

neurotransmitter
Chemical messenger specialized for communication from neuron to neuron

synapse
Space between two connecting neurons through which messages are transmitted chemically

synaptic cleft
A gap into which neurotransmitters are released from the axon terminal

glial cell
Cell in the nervous system that plays a role in the formation of myelin and the blood-brain barrier, responds to injury, removes debris, and enhances learning and memory

myelin sheath
Glial cells wrapped around axons that act as insulators of the neuron’s signal

resting potential
Electrical charge difference (-60 millivolts) across the neuronal membrane, when the neuron is not being stimulated or inhibited

threshold
membrane potential necessary to trigger action potential

action potential
electrical impulse that travels down the axon, triggering the release of neurotransmitters; positive particles rapidly flow into the axon until a maximal level is reached

absolute refractory period
time during which another action potential is impossible; limits maximal firing rate

graded potential
postsynaptic potentials that can be excitatory or inhibitory depending on whether positively or negatively charged particles flow across the neuronal membrane and in which direction they flow

excitatory postsynaptic potential (EPSP)
graded potential in a dendrite that is caused by excitatory synaptic transmission; positive ions allowed in which depolarizes the neuron

inhibitory postsynaptic potential (IPSP)
graded potential that is caused by inhibitory synaptic transmission; negative ions move in which hyperpolarizes the neuron

receptor site
location that uniquely recognizes a neurotransmitter

reuptake
means of recycling neurotransmitters; process by which the synaptic vesicle reabsorbs the neurotransmitter

endorphin
chemical in the brain that plays a specialized role in pain reduction

plasticity
ability of the nervous system to change

stem cell
a cell, often originating in embryos, having the capacity to differentiate into a more specialized cell

neurogenesis
creation of new neurons in the adult brain

central nervous system
part of the nervous system containing the brain and spinal cord that controls the mind and behaviour

peripheral nervous system
nerves in the body that extend outside the central nervous system

cerebral ventricles
pockets in the brain that contain cerebrospinal fluid (CSF), which provides the brain with nutrients and cushions against injury

forebrain
forward part of the brain that allows advanced intellectual abilities; aka cerebrum

frontal lobe
forward part of the cerebral cortex responsible for motor function, language, memory and planning

motor cortex
part of the frontal lobe responsible for body movement

prefrontal cortex
part of the frontal lobe responsible for thinking, planning and language

Broca’s area
language area in the prefrontal cortex that helps to control speech production

parietal lobe
upper middle part of the cerebral cortex lying behind the frontal lobe that is specialized for touch and perception

temporal lobe
lower part of the cerebral cortex that plays roles in hearing, understanding language, and memory

Wernicke’s area
part of the temporal lobe involved in understanding speech

occipital lobe
back part of the cerebral cortex specialized for vision

primary sensory cortex
regions of the cerebral cortex that initially process information from the senses

association cortex
regions of the cerebral cortex that integrate simpler functions to perform more complex functions

basal ganglia
structures in the forebrain that help to control movement

limbic system
emotional centre of the brain that also plays roles in smell, motivation and memory

thalamus
gateway from the sense organs to the primary sensory cortex

hypothalamus
part of the brain responsible for maintaining a constant internal state

amygdala
part of the limbic system that plays key roles in fear, excitement and arousal

hippocampus
part of the brain that plays a role in spatial memory

brain stem
part of the brain between the spinal cord and the cerebral cortex that contains the midbrain, pons, and medulla

midbrain
part of the brain stem that contributes to movement, tracking of visual stimuli, and reflexes triggered by sound

reticular activating system
brain area that plays a key role in arousal

hindbrain
region below the midbrain that contains the cerebellum, pons, and medulla

cerebellum
brain structure responsible for our sense of balance

pons
part of the brain stem that connects the cortex with the cerebellum

medulla
part of the brain stem involved in basic functions such as heartbeat and breathing

spinal cord
thick bundle of nerves that conveys signals between the brain and the body

interneuron
neuron that sends messages to other neurons nearby

reflex
automatic motor response to a sensory stimulus

somatic nervous system
part of the nervous system that conveys information between the CNS and the body, controlling and coordinating voluntary movement

autonomic nervous system
part of the nervous system controlling involuntary actions of our internal organs and glands; along with the limbic system, it participates in emotion regulation

sympathetic nervous system
division of the autonomic NS engaged during a crisis or after actions requiring fight or flight

parasympathetic nervous system
division of autonomic nervous system that controls rest and digestion

endocrine system
system of glands and hormones that controls secretion of blood-borne chemical messengers

hormone
chemical released into the bloodstream that influences particular organs and glands

pituitary gland
master gland that, under the control of the hypothalamus, directs the other glands of the body

adrenal gland
tissue located on top of the kidneys that releases adrenalin and cortisol during states of emotional arousal

lateralization
cognitive function that relies more on one side of the brain than the other

cerebral hemispheres
two halves of the cerebral cortex, each of which serves distinct yet highly integrated functions

corpus callosum
large band of fibres connecting the two cerebral hemispheres

cerebral cortex
outermost part of forebrain, responsible for analyzing sensory processing and higher brain functions