1.1 - 1.5 The Brain + Sleep

vocab from study guide, modules, and videos

neuron

cell that sends and receives messages

cell body

the part of a neuron that contains the nucleus; the cell’s life-support center

dendrites

receive messages from other neurons and cells, conducting impulses toward the cell body

interneurons

a neuron which transmits impulses between other neurons

axon

sends messages to other neurons, muscles, or glands

myelin sheath

fatty layer that speeds up neural signals

gilal cells

support neurons and help with learning and memory

action potential

an electrical signal a neuron fires

threshold

the level of stimulation required to trigger a neural impulse

excitatory neurotransmitters

encourages neurons to fire

inhibitory neurotransmitters

prevents neurons from firing

refractory period

the brief resting time after a neuron fires, neuron can’t fire

all-or-nothing response

neuron fires fully or not at all

synapse

the tiny gap where one neuron sends signals to another

reuptake

a neurotransmitter’s reabsorption by the sending neuron

substance P

pain neurotransmitter

nuerotransmitters

chemicals that cross the synapse to signal the next neuron, and tell the next neuron whether to fire

agonist

increases or mimics neurotransmitter action

antagonist

a molecule that increases a neurotransmitter’s action

Central Nervous System

Brain and spinal cord; decision maker of the body

Peripheral Nervous System

made up of subsystems; carries messages between body and CNS

Somatic Nervous System

controls voluntary movements of skeletal muscles

Automatic Nervous System

controls involuntary movements like breathing and digestion

Parasympathetic Nervous System

calms the body down following stress, “rest and digest”

Sympathetic Nervous System

prepares “ fight or flight” responses during stressful situations, puts the body in survival mode

Dopamine

involved in reward and motivation

Norepinephrine

neurotransmitter that increases heart rate and focus

GABA

Calms the nervous system

Endorphins

natural pain relieving neurotransmitters

Seratonin

mood stabilizing neurotransmitter

Oxytocin

bonding and love hormone

acetylcholine

neurotransmitter that helps muscle movement

Melatonin

sleep hormone

Leptin

hormone that reduces appetite

Ghrelin

Hormone that stimulates appetite

Adrenaline

fight or flight hormone

glumate

main excitatory neurotransmitter for learning and memory

EEG

record’s brains, electrical activity, using electrodes on scalp

lesion

destruction of brain tissue

reflex arc

an automatic response without conscious thought

MEG

measures magnetic fields from brain’s electrical activity

PET

shows brain activity by tracking glucose use during tasks

MRI

uses magnetic fields and radio waves to produce computer-generated images of soft tissue, scans show brain anatomy

fMRI

shows brain activity and function by tracking blood flow, also shows structure

brainstem

oldest part of the brain; controls automatic survival functions

medulla

the base of brainstem; controls heartbeat and breathing

amygdala

deals with fear and aggression

limbic system

involved in emotional making and memory

hippocampus

a neural center located in the limbic system; place a role in forming new memories but does NOT store memories

reticular activating system

regulates consciousness, filters sensory information and controls the sleep-wake cycle

microelectrodes

records single neuron activity

motor neurons

carry signals from the brain and spinal cord to muscles and glands

endocrine system

the body’s slower communication system; glands release hormones into the bloodstream

adrenal glands

glands above the kidneys that release epinephrine and norepinephrine to arouse the body during stress

thalamus

relay station for sensory information (except smell)

reticular formation

network in brainstem and thalamus; regulates arousal and alertness

optogenetics

control neurons with light

sensory neurons

information from the five senses travels towards the brain

Brain’s Job

interprets the message to make the next decision

Spinal Cord’s Job

carries messages between the brain and the body

Occipital lobes

back part of the cerebral cortex that processes visual information

Temporal lobes

sides of the cerebral cortex above the ears that processes auditory information, mostly from the opposite ear

cerebral cortex

main control and information-processing center

frontal lobes

front part of the cortex; handles speaking, muscle movements, planning, decision making

parietal lobes

top-middle part of the cortex; processes sensory info like touch and body position

Somatosensory Cortex

front part of the parietal lobes that register and processes body touch and movement sensations

Association areas

cerebral cortex regions involved in higher mental thinking; learning, remembering, and speaking, but NOT basic or sensory tasks

nuerogenesis

the formation of new neurons