Neuroscience

neuron

nerve cell that make up the nervous system & transmit information

what are the three different types of neurons?

sensory neurons, motor neurons, interneurons

nervous system

all the neurons in our bodies used to communicate brain messages

the nervous system can be broken down into

peripheral nervous system & central nervous system

how does an impulse travel from a single neuron

dendrites—> cell body (soma)—> nucleus—> axon—→ terminal branches—→ synapses

dendrites

receive messages/ signals from other neurons or sensory receptors

cell body (soma)

cells life support system

what is the axon covered with

myelin sheath

what does the myelin sheath do to the action potiential

speeds up neural impulse when traveling axon

neurons release neurotransmitters into the

synapse

neurotransmitters are divided into what two groups?

excitatory & inhibitory

steps of an action potential

firing of neuron—> depolarization—> depolarization—> refractory period—> threshold—> all or none response

during the refractory period what cannot happen?

release neurotransmitters or have another action potential

threshold

level of stimulation in order to trigger neural impulse

excess dopamine

schizophrenia

dopamine deficiency

Parkison’s disease

depression

all or none response

a neurons reaction to either firing or to not firing

the 2 ways NT are removed from synapse

reuptake & enzymes

what do enzymes do in synapse?

break down excess NT in synapse

reuptake

axon terminals reabsorb the excess NT so they can be reused.

sensory/afferent neurons

message comes from senses/receptors & goes to spinal cord (interneurons)

interneurons

neurons found in brain/spinal cord

message comes from sensory neurons going to motor neurons

motor/efferent neurons

message coming from interneurons going to effectors

effectors

muscles/glands

path of reflex arcs

receptor—> sensory neurons—> interneurons—> motor neurons—> effectors

receptor

senses- eyes/skin/ears/nose/taste buds

agonists drugs

do the same job as neurotransmitters (mimic)

antagonists drugs

block neurotransmitters from doing its job

reuptake inhibitar

stops reuptake of neurotransmitters

function of acetylcholine

enables muscle action, learning, & memory

serotonin deficiency

depression

excess endorphins

runners high

norepinephrine deficiency

ADHD

Depression

what does endorphins do?

take away pain

acetylcholine deficiency

Alzheimer’s

paralysis

what is acetylcholine responsible for?

memory

muscle movement

excess glutamate

migranes

seizure

GABA deficiency

anxiety

seizures

what does GABA& dopamine do to neurons

causes other neurons to stop firing

what is the peripheral nervous system consist of

autonomic and somatic nervous system

what does autonomic system consist of

sympathetic & parasympathetic nervous system

sympathetic nervous system

fight or flight

arouses

increases heart rate

decreases digestion

parasympathetic nervous system

rest & digest

calms

increases digestion

slows heart rate

somatic nervous system

in charge of controlling voluntary movements of our skeletal muscles

what are the 4 lobes in the cerebrum/cerebral cortex

frontal lobe, parietal lobe, occipital lobe, & temporal lobe

where is cerebrum?

cerebrum is in the front of the brain

where is the hindbrain/brainstem & what is its function?

lower back part of the brain & it helps keeps us alive by being responsible for autonomic survival functions

what are the parts of the brainstem?

Medulla, pons, reticular formation, cerebellum

reticular formAAAAtion function

arousal, attention, alertness, awake/asleep

medulla function

breathing, heartrate

sends signals to autonomic nervous system

pons function

control facial expression, connects 3 parts of brain

cerebellum

balance, posture, coordinates movement

what are the parts of the limbic system (LAAHT)

amygdala, hypothalmus, hippocampus, & thalamus

AAAmygdala function

involved processing fear & aggression

hypothalamus function

maintains homeostasis- controls body temp, hunger, thirst, sex drives, hormones

hippocampus function

creates memories

(hally the hippo)

thalamus

sends messages from senses coming up spinal cord to the cerebral cortex

parts of frontal lobe

motor cortex, pre-frontal cortex, broca’s area

motor cortex function

voluntary movement

pre-frontal cortex movement

rational, logical thinking & judgement

broca’s area function

allows ability to speak

parts of the parietal lobe

somatosensory cortex (sensory cortex), angular gyrus

somatosensory cortex (sensory cortex) function

allows to feel touch

sense of touch

angular gyrus function

allows to read

occipital lobe part & function

visual cortex- helps to see

parts of temporal lobe

auditory cortex, wernicke’s area

auditory cortex function

allows to process sounds sensed by ears

wernicke’s area function

understand language

the corpus callosum

large band of neural fibers that connect two brain hemisphere & messages carrying between

split brain

condition resulting from surgery that isolates two brain hemispheres by cutting the fibers connecting them

left hemisphere controls

right half of body

right hemisphere controls

left half of body

what is left side of brain responsible for?

logic, language, facts, computation, analysis

what is right side of brain responsible for?

creativity, imagination, intuition, daydreaming, feelings

plasticity

brains ability to change shapes & form new connections

high during childhood

lesion

removal or destruction of part of brain

neurogenis

forming of new neurons

endocrine system

sets of glands the release horomones into bloodstream

chemical messengers

adrenal glands

helps arouse body in times of stress

trigger fight or flight response

release epinephrine & norepenpherene

pituitary gland

regulates growth hormone & other glands under control of hypothalamus

pancrease

regulates level of sugar in blood

pineal gland

produces melatonin & regulates circadian rhythm

thyroid gland

affects metabolism

gonads (testes & oavries)

sex horomones

parathyroids

regulate level of calcium in blood

hypthalmus

controls pituitary gland & releases hormones

types of method to study brain

EEG, CT scan, PET scan, MRI, fMRI

EEG

does NOT show pic of brain

amplified recording of waves of electrical activity in brain

CT scan

series of X-ray photographs at diff angles

PET Scan

visual display of brain activity

uses radioactive glucose

MRI

scans show brain anatomy

uses magnetic fields & radio waves to produce computer generated images

fMRI

reveals blood flow & brain activity by comparing MRI scans

show brain function & structure

phineas gage

severed frontal cortex & amydala, causing him to be aggresive, irritable

clyde wearing

virus attacked hippocampus so he could not create new memories