EXAM 2 Module 3 Flashcards
all senses go to the thalamus except…
smell
___ does not have separate receptor cells; they are __________ instead
smell; olfactory receptor neurons
overall outline of nervous system
sensory receptor
sensory input (afferent)
integration center (brain/spinal cord)
motor output (efferent)
effector
central nervous system (CNS)
brain
spinal cord
(integration centers)
peripheral nervous system (PNS)
sensory input
motor output
sensory inputs (afferent/efferent?)
afferent
motor outputs (afferent/efferent?)
efferent
functional organization of the sensory system
physical stimulus (reaches threshold)
receptors (transduction, AP)
afferent neurons (conduction)
brain (processing, AP)
perception
conscious interpretation of the external world
perception
conversion of one form of energy to into another
transduction
sensory receptor arrangements
free nerve endings (dendrites)
*specialized nerve endings on primary afferent neurons (encapsulated)
*specialized receptor cells associated with primary afferent neurons
vision sensory receptors
photoreceptors (rods, cones)
hearing and touch sensory receptors
mechanoreceptors (hearing, touch)
nociceptors (pain)
thermoreceptors (temperature)
smell and taste sensory receptors
chemoreceptors
graded response to a stimulus that may be depolarizing or hyperpolarizing
receptor potential
response is proportional to stimulus intensity
graded
receptor potential has a threshold in stimulus _____ that must be reached to trigger an AP
amplitude
receptor potential involves opening or closing of specific ________ in receptor membrane
ion channels
receptor potentials can work to trigger an AP within the ______ or _______
same cell; adjacent cell
receptor potential transduction current typically carried by _____
Na+
stimulus that occurs when a cell’s membrane potential becomes more negative than its resting potential, less likely to fire AP
hyperpolarized
ex: when it gets dark and photoreceptors in retina respond
hyperpolarization stimulus
stimulus that occurs when a cell’s membrane potential becomes less negative (more positive), more likely to fire an AP
depolarized
ex: when you touch something hot and nociceptors in skin are activated
depolarization stimulus
receptor potential is propagated passively towards the neuron’s ________
trigger zone
receptor potential threshold is around -___mV, and if it’s reached, an AP will fire
-55mV
AP frequency _______ (changes/does not change?) AP amplitude
does not change
process where stronger stimuli excite more receptors and afferents
recruitment
process where interneurons suppress activity of neighboring neurons
lateral inhibition
lateral inhibition does what 2 things
increases contrast of sensory perception
sharpens perception of stimulus location
maximum pressure difference between zones of compression and rarefaction in sound waves
amplitude of sound wave
loudness of sound is directly related to ______
amplitude
pitch of sound is related to its ______
frequency
sound waves enter the __________
external auditory canal
when sound waves enter the external auditory canal, it causes the _________ at the end of canal to vibrate
tympanic membrane (eardrum)
outer ear structures
external auditory canal
middle ear structures (air filled space)
(in order)
eardrum
malleus
incus
stapes
inner ear structures (spiral shaped, fluid-filled space in temporal bone)
cochlea
3 chambers of cochlea divided lengthwise
scala vestiboli (innermost)
cochlear duct (middle)
scala tympani (outermost)
how hair cells transduce sound:
- cochlear duct is filled with fluid containing high _____
- when stereocillia bends in direction of the tallest stereocillium, tip links _______, K+ channels _____, K+ enters, cell ______, and ______ is released
- AP in _____ neurons
K+;
stretch; open; depolarizes; glutamate;
afferent
how hair cells transduce sound:
- when stereocillia bundle bends in direction of the shortest stereocillium, tip links _____, K+ channels _____, K+ current stops, cell _______, and neurotransmitter release _______
- basilar membrane vibration produces _________ of neurotransmitters by _______
slack; close; hyper polarizes; decreases/stops;
bursts of release; hair cells
louder sound related to higher __________
AP frequency
hair cells in ampulla during stimulation (depolarization)
bend in direction of tallest stereocillia
hair cells in ampulla during inhibition (hyperpolarization)
bend in direction of shortest stereocillia
hair cells in ampulla during resting activity
straight, not bent
effects of bending the stereocillia
- increase/decrease of neurotransmitter release from resting state
- increase/decrease of AP frequencies
- directions of the rotation and acceleration
nervous system pathway
receptors
AP
afferent neurons
brain
AP
efferent neurons
effector
nerve cells in the spinal cord that send their axons to innervate muscles
motor neurons
________ travel down the motor neuron and branch into many terminals near its target
APs
_________ is released in the neuromuscular junction
acetylcholine
motor neurons are the ___________ out of the CNS
final common pathway (efferent)
motor control hierarchy
starts with idea
high
- pre-command level, planning
- voluntary movements
middle
- projection level, instructions
- rhythmic motor patterns
low (local)
- segmental level, central pattern generators
- reflexes
ends with movement
motor control high level structures
cortical association cortex
cerebellum
basal ganglia
motor control middle level structures
motor cortex/brainstem
motor control low (local) level structures
spinal cord
interneurons
motor neurons
afferent neurons
afferent information about the position of the body and its parts in space
proprioreception
local level neurons receive motor programs from middle level and determine which motor neurons will be _________ and the _________
activated/inhibited; timing
motor neurons exit the CNS and project to the _______
muscles
all coordinated controls of muscles, timing, duration, and strength are through __________
motor neuron AP
reflex that involves only one synapse between the sensory neuron and the motor neuron
monosynaptic
reflex that involves one or more synapse, meaning interneurons are involved in the pathway
polysynaptic
monosynaptic reflexes _______ the stretched muscle to ________
activate; contract
interneurons in polysynaptic reflexes release _______ signals onto the motor neurons of the antagonistic muscle
inhibitory
when the agonist muscle contracts (in response to stretch), the antagonistic muscle (muscle opposite to the stretched one) must _____ to allow smooth movement
relax
the activation of neurons to one muscle with the simultaneous inhibition of neurons to its antagonistic muscle
reciprocal innervation
feedback from muscle stretch receptors:
- muscle spindles detect changes in _______ and ________
muscle length; rate of stretch
feedback from muscle stretch receptors:
- afferent feedback: sensory neurons from muscle spindles transmit information about muscle length and rate of stretch to _____ and _____
spinal cord; brain
feedback from muscle stretch receptors:
- reflex pathways
- monosynaptic: ________ of stretched muscle to counteract the stretch
- polysynaptic: interneurons inhibit motor neurons of the ___________, allowing agonist muscle to contract freely
contraction; antagonistic muscle
the stretch reflex acts as a _______ feedback mechanism
negative
a form of electromagnetic radiation or waves
light
distance between successive peaks of EM radiation
wavelength
visible spectrum range, capable of stimulating the receptors of the eye
400-700nm
first rainbow color
violet (400nm)
colored part of eye
controls size of pupil and amount of light that enters eye
iris
allows light to get to retina
pupil
layer of tissue containing the photoreceptors
retina
axons of ganglion neurons in the retina that carry visual information to brain
optic nerve
light pathway through the retina
goes from front of retina to back of retina
inner layer to middle layer to outer layer
organization of the retina from front to back
axons of optic nerve
ganglion cells
amacrine cells
bipolar cells
horizontal cells
photoreceptors
who suffers from color blindness more (males/females?)
males
types of photo receptors in retina
rods and cones
segment that has membranous discs or folds with photopigments which absorb light
outer segment
segment that has basic cell machinery
inner segment
synaptic terminal releases ________ as neurotransmitter
glutamate
photoreceptor that responds to low light, has more photopigment, highly sensitive
rhodopsin
rod
photoreceptor that responds to bright light, less photopigment, low sensitivity, high visual acuity
photopsins
cone
T/F: photoreceptors are neurons
false - they are receptor cells
~10,000 in the lingual papillae (tongue)
taste buds
in taste buds, _________ respond to the presence of given chemicals resulting in neurotransmitter release
receptor proteins
tastants must be ________ in muscus to reach taste receptor cells
dissolved
pore allows saliva with ______ to contact gustatory/receptor cells
tastants
apical receptor cell membranes extend to _______
surface (hair/microvilli)
basal membranes contact and synapse with __________
primary afferents
5 taste submodalities
umami
sweet
bitter
sour
salty
gustation transduction for umami, sweet, and bitter
*G-protein coupled receptors
signal transduction pathway
ligand sensitive ion channels
receptor potential
AP in primary sensory neurons
gustation transduction for sour and salty
*ion channels
receptor potential
AP in primary sensory neurons
many different chemicals can generate the sensation of taste by differentially activating ________ basic types of taste receptors
one or more
measures electrical activity in the brain’s neurons
EEG
EEG patterns are largely due to __________
synchronous graded potentials (postsynaptic potentials)
the state of being aware of and responsive to one’s surroundings
consciousness
states of consciousness
levels of alertness (awake, drowsy, or asleep)
conscious experiences
experiences a person is aware of (thoughts, feelings, perceptions) vs. (sleep walking, drunk)
part of the brain responsible for emotional reactions
limbic system (amygdala, prefrontal cortex, hippocampus)
reward pathway in the brain, associated with motivation
mesolimbic dopamine pathway
functions of sleep:
- sleep is _________ the rest of the body or brain
- sleep is important for conserving, strengthening, and modulating ______ in pathways involved in learning and memory
- sleep deprived people show deficiency in ________
- sleep is a ________ requirement like food and water, limit is __ days
much more than;
synapses;
memory retention;
homeostatic; 11
brain wave sleep patterns from lightest to deepest
beta
alpha
theta
delta
14-30 Hz
awake, alert
beta
8-13.9 Hz
pre-sleep, drowsiness
alpha
4-7.9 Hz
dreaming (REM)
theta
0.1-3.9 Hz
dreamless and deep sleep, totally unconscious
delta
beta -> alpha
become drowsy
alpha -> beta
become awake
EEG arousal
from deep to light sleep
EEG arousal is associated with the act of…
paying attention to a stimulus
theta waves begin to be interspersed among the alpha pattern
low amplitude, mixed frequency waves
stage N1 (light sleep)
high-frequency bursts called sleep spindles and large-amplitude K complexes occasionally interrupt the theta rhythm
high amplitude waves, high frequency
stage N2
delta waves first appear and gradually become dominant (slow-wave sleep)
high amplitude, low frequency
stage N3 (deep sleep)
REM sleep pattern is similar to _____
beta
uninterrupted sleep cycle
4-5 cycles, 90-100 mins
N1
N2
N3
back to N2
REM
where short term declarative memory occurs in brain
hippocampus and other limbic system structures
where long term declarative memory occurs in brain
many areas of association cortex
where short term procedural memory occurs in brain
widely distributed
where long term procedural memory occurs in brain
basal nuclei
cerebellum
sensorimotor cortex
L-dopa can increase…
dopaminergic activity
factors that affect receptor potential magnitude
stimulus strength
summation
receptor adaptation
(not AP)
what is associated with memory formation
long term potentiation
long term depression
altered gene expression
(not L-dopa conversion to dopamine)
