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