Lecture 3 Flashcards
Neuron
cells in the nervous system that communicate with on another to perform information-processing tasks
parts of a neuron
cell body, dendrites, axon, myelin sheaths, nodes of ranvier, synapse
cell body
coordinates information processing tasks and keeps the cell alaive
dendrites
recives information from other neurons and relays it to the cell body
axon
transmits information to other neurons, muscles or glands
myelin sheath
insulating layer of fatty material
nodes of ranvier
increase efficiency of signal transmission
synapse
the junction or region between the axon of one neuron and the dendrites or cell body of another
types of neurons
sensory
motor
interneurons
sensory nuerons
TO BRAIN (eternal world-> spinal cord -> brain)
motor neuron
TO BODY (spinal -> muscles -> movment)
interneurons
neurons that connect sensory neurons, motor neurons or other interneurons)
electric signaling
communicating information within a neuron
1. resting potential: -70 millivolts ( Na/k pump pumps 3 Na+ out and 2K+ in –> negative)
2. threshold is met (-55 mv)
3. cell becomes positively charged (+40)
4. action potential: an electric signal that is conducted along an axon to a synapse
5. refractory period has to reset to 70
chemical signalling
synaptic transmission between neurons, when an action potential reaches the end of on axon at the terminal button and a neurotransmitter is released into the synapse, collected at the receptor of the receiving neuron
how do neurotransmitters leave the synapse
reuptake: pump reabsorbes neurotransmitters
enzyme deactivation: enzymes eat the neurotransmitters
autoreceptors: concentration of NT are so high that the same terminal button that is releasing the NT is connected a triggered so it closed the gap stopping the release of NTs
acetylcholine
voluntary muscle control, memory and learning (Alzheimers)
Dopamine
regulated motor behavior, pleasure and emotional arousal (parkinsons)
norepinephrine
influences mood and arousal (depression)
serotonin
regulates sleep, dreaming, mood, aggression
endorphins
chemicals that act within the pain and pleasure pathways (runners high)
how does L-dopa help parkinsons
precursor to dopamine
how does prozac help depression
SSRI: selective serotonin reuptake inhibitor (prevents reuptake int he synapes so it increase concentration)
the nervous system
central nervous system and peripheral nervous system
central nervous system
brain and spinal cord
spinal reflexes: simple pathways that rapidly generate muscle contractions
peripheral nervous system
connects CNS to organs and muscles (somatic + autonomic)
somatic nervous system
conveys information in and out of CNS
autonomic nervous system
conveys involuntary and automatic commands to body (sympathetic ad parasympathetic)
division of somatic NS
sensory: body to brain
motor: braint o body
division of autonomic NS
sympathetic: prepares the body for action
parasympathetic: helps body return to normal resting state
major divisions of the brain
forebrain, midbrain, hindbrain
parts of the hindbrain
pons, cerebellum, medulla, reticular formation
function of pons
relays info between cerebellum and brain
function of cerebellum
fine motor skills, coordination, balance
function of medulla
coordinates heart rate, circulation, and respiration
function of reticular formation
regulated sleep, wakefulness and arousal level
function of midbrain
important for orientation and movement
function of forebrain
critical for complex cognitive, emotional, sensory and motor function
parts of forebrain
cerebral cortex and subcortical stuctures
what is the cerebral cortex
outer layer of brain, divided into 2 hemispheres
where are the subcortical structures
under the cerebral cortex, center of brain
what are the subcortical structures in the forebrain
thalamus, hypothalamus, pituitary gland, hippocampus, amygdala
function of the thalamus
relays information from senses and transmits the information to the cerebral cortex
function of the hypothalamus
regulates body temperature, hunger, thirst and sexual behavior
function of pituitary gland
“master gland” releases hormones
hippocampus
make new memories
amygdala
emotional processes, formation of new emotional memories
what are the lobes of the cerebral cortex
made of 2 hemispheres (attached by the corpus callosum) that are divided into 4 lobes
occipital
parietal
temporal
frontal
function of occipital lobe
primary visual cortex
function of parietal lobe
processes information about touch (somatosensory cortex)
function of the temporal lobe
hearing and language
function of frontal lobe
motor cortex, planning, judgement, memory
who was phineas gage
what is contralateral representation in the brain
right hemi controls left body
left hemi controls right body
left hemi is responsible for
language
right hemi is responsible for
visual-spatial
