terms Flashcards
Oligodendrocytes assist the myelin sheath where?
Central Nervous System
Schwan cells assist the myelin sheath where?
Nerves outside the brain and spinal cord
What function do microglia serve? What do they play a role in?
Immune function, play a role in learning and memory.
What is the degeneration of Microglia linked ith?
Alzheimer’s
What are asrocytes use for?
Formation of the immune system for the brain
What disease are astocytes linked to?
Neurodegenerative diseases
What % water is a neuron made of?
80%
What are the dissolved chemicals in a neuron?
Na+, Cl-, K+
Acetylcholine
Excitatory
Learning, muscle action
Glutamate
Excitatory
Learning, movement
GABA
Inhibitory
Learning, anxiety regulation through inhibition of neurons
Dopamine
Both
Learning, reward/pleasure
Serotonin
Both
Elevation/depression of mood
Norepinephrine
Both
Elevation/depression of mood
Endorphins/Enkaphlains
Both
Regulation of pain responses
CT scan
Computerized Tomography
Uses x-rays that pas through body, can generate images of “slices” of the body
ex. detect changes in structure to to disease
pros/cons of CT scan
pro:
- Fast, cheap, non-invasive
con:
- radiation exposure
- only less us see the structures of the brain, not the brain in action
MRI
Magnetic Resonance Imaging
Uses magnetic fields to image alignments of H+ ions (diff tissues have diff amts of water
ex. can detect changes in structure due to disease
pros/cons of MRI
pro:
- noninvasive, great precision, no radiation
con:
- very expensive
- cannot have biomedical devices or metal in patients
- just gives an image of the brain, not the brain in action
fMRI
functional MRI
uses magnetic fields to image alignments of H+ ions. exposed to magnetic field –> tracks oxygenated blood
More active parts of brain will consume more oxygenated blood
ex. can measure activation during task/stimulation
DTI
Diffusion Tensor Imaging
tracks and images water movement alone neural pathways, can measure density of neural tracts (bundles of axons). Tracks nerves of the brain and the connections between different areas
ex. study white matter degeneration in disease
pros/cons of DTI
pro:
- noninvasive
- no radiation
- no injections
con:
- interpretation can be difficult in tracts with diff kinds of fibers
pros/cons of fMRI
pro:
- noninvasive
- no radiation
- no injections
con:
- cardiovascular disease/compromise function can make measurements unreliable –> elay between stimulus/output
- shows the brain in action
PET/SPECT
Single Photon Emission Computed Tomography
Uses ingested radioactive compound to track molecular changes, person is injected with radioactive substance
ex. visualize the activity of specific neurotransmitters
What substance are patients usually injected with for a PET scan?
Glucose
Pros/cons of PET/SPECT
pro:
- can see molecular changes in real time
- determine which part of brain is more active
- can see brain in action
con:
- radiation exposure
What is psychology
SCIENTIFIC study of how we think, feel, and behave
Why can we not rely on common sense?
common sense for one person may not be common sense for another
it does not generate new knowledge
Rationalism
We must use pure logic reasoning, and critical thinking
–> senses are deceiving and we cannot use them to learn about the natural work
Empiricism
We must use our senses, experiences, and systematic observations
What did Kant say?
We must use both are sense and our logic so that we can put things together in a coherent and meaningful way
what is the scientific method
- identify
- gather info
- develop hypothesis
- design/conduct experiment
- analyze data and draw conclusion
- restart process
what is a hypothesis?
a tentative statement
what is the requirement for a hypothesis?
must be falsifiable
Henry Molaison case study
as a boy, experienced mild seizures after falling off his bike and hitting his head
last resort → bilateral ablation (medical procedure to remove or otherwise destroy tissue) to ventral medial temporal lobes
- removed hippocampus
seizures stopped, but he couldn’t form new memories
what are the 2 divisons of the nervous system
- central nervous system
- peripheral nervous system
what are the cells of the NS
neurons, glial cells
what does the NS do
receive info from the external world and analyze/organize/interpret the information in a meaningful way
send messages to muscles so that they can produce behaviours
what do neurons do?
basic unit of communication that is an electrochemical process
what is action potential
electrical impulse that travels down the neuron and leads to the release of neurotransmitters
what are neurotransmitters
chemicals that carry messages to other neurons
soma
nucleus/DNA inside soma
manufactures everything the neuron needs to survive
dendrites
increase surface area of soma without taking up space
antennas of neuron, receives messages from other neurons
axon
where action potential travels down until it reaches terminal buttons
axon branches/terminals
little knobs at the ends of axon branches that contain the neural transmitters
terminal buttons
action potential release neural signals when they reach the terminal buttons
myelin sheath
white, fatty-like substance that provides insulation to axon
allows information to transmit very fast
do all axons have myelin sheath?
NO
synpase
place where neurons meet to communicate
synaptic cleft/gap
space between 2 neurons at the synapse
presynaptic vs postsynaptic neuron
presynaptic sends out messages
postsynaptic receives messages
what are the glial cells to neurons
NANNIES of neurons
help with development, nutrition, insulation, protection, cleaning
what is the function of glial cells
involved in higher mental functioning -> learning, memory, intelligence
linked with brain diseases
ions in a neuron at rest?
- negatively charged INSIDE (-70mV)
- positively charged OUTSIDE
- membrane is polarized
inhibitory messages
instruct neuron not to fire
how do inhibitory neurons change the concentration of ions
from -70 –> -77mV
HYPERPOLARIZED
excitatory neurons
instruct neuron to fire
how to excitatory neurons change the concentration of ions
from -70 –> -63 mV
DEPOLARIZED
when do neurons fire their signal
about -50mV
nodes of ranvier
gaps in the myelin sheath
what are nodes of ranvier for
channels so that ions can get in/out of the neuron
what happens chemically when neurons receive inhibitory messages
Cl- channels open and ions move INSIDE the neuron (influx)
inside of neuron is more negative (HYPERPOLARIZED(
what happens chemically when a neuron receives excitatory messages?
Na+ channels open and ions move INSIDE neuron (influx)
increases positive charge in neuron
if it charge reaches -50mV(threshold of excitation) neuron will fire
what happens after Na+ channels open in order to go back to its resting potential?
K+ channels open and ions leave neuron (efflux)
neuron reaches -70mV again
refractory period
period where neuron will not fire again if stimulated due to hyperpolarization
more negative than -70 due to K+ ions moving out of neuron
where does a neurotransmitter attach
to receptor sites
reuptake
neurotransmitters go back to the neuron that released it and is recycled for future use
degradation of neurotransmitters
enzyme breaks it down
why must a neurotransmitter be deavtivated
it will deliver the same message over and over again
overexcited the neurotransmitter
what are abnormal levels of dopamine linked to
shizophrenia
where do drugs produce their levels at
synapse
agonists (drugs)
enhance activity of neurotransmitters
can mimic a neurotransmitter and will deliver the same message
antagonists (drugs)
decrease/block activity of a neurotransmitter
competitive –> direct (drugs)
directly compete with neurotransmitters for parking spot
non-competitive –> indirect (drugs)
will not compete for same parking spot, will find another spot to attach to
enhances, reduces, or blocks activity of neurotransmitter
brainstem
connects brain to spinal cord
–> started where spinal cord ends
LIFE CENTER –> contains structures that control vital functions essential for survival (medulla, pons, RAS)
how is the brainstem a crossover point
info coming from LEFT will cross to RIGHT and vice versa
pons functions
connect CNS to PNS
regulate basic functions we don’t consciously think about
regulate arousal, coordinate senses, control facial expressions
what is RAS
network of neurons
where is RAS located
center of medulla and pons
RAS functions
bridges functions of body and brain via connections to spinal cord and thalamus
regulate levels of arousal and focus
to what disorder is RAS linked to
ADHD
cerebellum
controls voluntary movement, balance and muscle tone
–> involved in motor movements that become automatic
what amount of the brain does the cerebellum take up
1/10
what is the cerebellum linked to
learning, memory, creativity, reasoning, language
autism
getting “drunk”
thalamus
relay station –> all senses except smell send info to thalamus which then releases it to other areas of the brain
filters information and highlights what is important
what is the thalamus linked to
goosebumps
limbic system
contains hippocampus and amygdala
linked to emotion, memory, learning, motivation
hippocampus
involved in the formation of new memories and maintenance of cognitive maps
what is the hippocampus vulnerable to
chronic stress
what part of the brain does alzheimer’s affect first
hippocampus
amygdala
associated with aggression and the experience of emotions, especially fear
also associated with perception of emotions and emotional memories
main function of amygdala
detect threats in our environment and sound the alarn
cerebral cortex
outer layer of the brain
–> makes us highly adaptable
how much of the cortex can we see
1/3
2 hemispheres of the cortex
right hemisphere: controls right side of body
left hemisphere: controls left side of body
corpus callusom
bundle of nerve fibers
–> 2 hemispheres use to communicate with each other
4 lobes of each hemisphere
frontal, parietal, temporal, occipital
2 areas of each lobe on each hemisphere
primary, association
primary areas of each lobe
linked with processing of motory/sensory info
association areas of each lobe
linked with higher and more complex mental functioning
endocrine system
major communication system that consists of all glands in the body
3 types of hormones
homeostasis, reproductive, stress
pituitary gland
master gland of the endocrine system, boss of almost all glands of system
hypothalamus
controls pituitary gland
how does the NS affect the endocrine system
hypothalamus
how does the ED influence the Ns
brain
transduction
brain only understands electrochemical messages, so physical energy must be translated into a message the brain can understand
transmission
message must be transmitted to brain for processingse
sensory receptors
respond to physical energy/stimulation from natural world
the ones that detect, transduce, and transmit
bottom-up processing
collect raw data from world and sent it to brain
top-down processing
brain uses excisting knowledge, memories, beliefs, in order to interpret information
prosopagnosia
when the eyes work, but no perception
psychophysics
scientific study of how physical characteristics of the physical world trsnlate into psychological experiences
absolute threshold
minimal amt of energy that must be there for us to detect it 50% of the time
difference theshold (JND)
minimum amount of change in stimulation for us to detect it 50% of the times
weber’s law
ability to notive the difference between 2 stimuli is proportional to the intensity or size of the stimulus
signal detection theory
ability to detect a stimulation doesn’t depends only on how the stimulation is –> large number of factors
ex. how healthy we are, fatigue, motivation, mood
perception
brain taking raw sensory data and interpreting it in a meaningful way
what do you need to see
light
light is a form of ???
electromagnetic radiation
what is the range of visible light
400-700nm
what colour are long waves
red
amplitude
height of wavelength
rods and cones (retina)
sensory receptors for vision, connected to bipolar cells
bipolar cells
connected to ganglion cells
ganglion cells
axons bunch up together to form the optic nerve
optic nerve
carry visual information to brain
blind psot
where optic nerve leaves the eye
–> no rods/cones in that area so nothing to detect light
fovea
center of retina, responsible for visual activity
allows us to see fine detail
where are rods found
in the periphery
where are cones found
heavily concentrated in fovea
what is the connction for cones - bipolar cells
1-1
** multiple rods for one bipolar
cone function (retina)
needs lots of light to activate
allows us to see colour
rods function (retina)
activated by little light, used when dark
involved in peripheral vision
simple cell vs. complex cell
cimple cell: respond to small stationary bars of light oriented at specific angles
complex cell: respond to lines of particular orientation moving in specific directions
parietal lobe
WHERE pathway
dorsal stream, lets us know where an object is in space, whether it is moving or not
temporal lobe
WHAT pathway
ventral stream
limbic system
responsible for emotional reactions
trichromatic theory
3 primary light colours, combining them allows us to see more colours
compl. afterimages
continue to perceive an objecte ven though we aren’t looking at it anymore
4 RGBY
4 primary light colours –> red, green, blue, yellow
3 antagonistic colour system
2 antagonistic colour system
red and green RG
blue and yellow BY
black and white BW
RG
mneurons respond to RG light, but respond in opposite ways
–> red excites neuron, green inhibits
principle of figure-ground
certain information is given priority over the background
principle of proximity
objects close to one another will be grouped together
principle of similarity
objects physically cimilar will be grouped together
principle of closure
tend to perceive whole objects, even when part of that information is missing
principle of good continutation
if lines cross each other/are interrupted, people tend to still see continuously flowing lines
principle of common fate
objects moving together will be grouped together
depth perception
brain uses bottom-up and top-down processing to understand
2 kinds of depth cues
- monocular (1 eye)
- binocular (2 eyes)
3 characteristics of sound waves
frequency(Hz), –> pitch amplitude(Db) –> loudness, complexity –> timbre (what makes a sound unique)
pinna
captures and funnels sound waves into auditory canal
auditory canal
soundwaves travel until it reaches the eardrum
ossicles (eardrum)
tiniest bone in body, vibration cauyses oval window to vibrate
oval window (eardrum)
membrane in ear
cochlea(eardrum)
fluid inside cochlea, vibration from oval window causes fluid in cochlea to move in waves
basilar membrane (eardrum)
waves of cochlear fluid cause basilar membrane to vibrate
cilia (hair cells) (eardrum)
vibration of basilar membrane causes cilia to sway and bend
–> they fire
sensory receptors of the ear
auditory nerve(eardrum)
hair cells detect, transduce, transmit information from brain via auditory nerve
carries info to brain
thalamus MGN
info goes from auditory nerv to here
auditory cortex (temporal lobes)
stops here after going to thalamus MGN
tonotopic organization
auditory systems maintains this from basilar membrane to auditory cortex
simple sounds are processed in ???
lower regions
why do some neurons that process auditory info have faster action potential and larger terminal buttons
timing is critical to understand
place theory
sound waves of difference frequencies will activate different areas of the basilar membrane
HF wound waves
activate hair cells located at BEGINNING of membrane
LF sound waves
activate hair cells located at the END of the basilar membrane
frequency theory
soundwave of different frequencies will affect rate of firing
2 binural cues
time of arrival, loudness
cutaneous senses
sense more than just touch
mechanoreceptors
responsible for the sense of touch
what are the merkel and meissner receptors for
pressure
nociceptors
sensory receptors that detect, transduce, and transmit info about pain
neurological gate
state of gate is linked ans associated whether we experience pain or not
small nerve fibers (S-fibers)
mostly carry pain info –> gate is opened, likely to feel pain
large nerve fibers (L-fibers)
mostly carry info NOT related to pain –> gate is closed, likely to feel little pain
T-cells
middle men between fibers and gate
–> must be activated for gate to open
olfactory receptors (smell)
scent must reach our nasal cavities and olfactory receptors for us to smell
olfactory epithelium(smell)
membrane filled with mucus
glomeruli (smell)
located in olfactory bulb, sends info to different parts of the brain, including limbic system
regeneration of olfactory cells
cells regenerate every few weeks, but lose numbers as we age
filiform papillae (tongue)
entire surface of tongue, doesn’t have taste buds
fungiform papillae (tongue)
tips and sides of tongue
foliate papillae
back of tongue
circumvallate
back of tongue
4 basic senses
SSSB: sweet, sour, salty, bitter
umami
japanese 5th sense linked with savory foods
bimodal neurons
neurons that respond to more than one sense
kinesthesis
allows us to know where are body is
sensory receptors: proprioceptors
vestibular sense
balance
2 organs linked with sense of balance
- semicircular canals: sense rotation of head
- vestibular sacs: respond to cues of balance and posture
gustatory cells
sensory receptors for taste found in taste buds
papillae
bumps on tongue
experimental group vs control group
experimental: expose to IV
control: not exposed to IV
confounding variable
a factor that COULD affect the variable we are studying
placebo
substance that is inert, does not have any therapeutic value whatsoever
we feel better based on belief and belief only
representative sample
must closely represent the population of interest
chosen by random sampling
random sampling
every single person in the population of interest has an equal chance to be included in the sample, chosen by chance and only chance
stratified random sample
take population of interest and divide it into different groups we’re interested in (STRATA)
simple random sample
extract sample from population of interest using random sampling
acquiescence bias
tendency for subject to agree with whatever the researcher is asking
volunteer bias
volunteers may not be a representative of the population of interest
illusory superiority
tendency for people to perceive themselves as better than average
naturalistic observation
researchers do their research in the real world, can only observe
2 divisions of the PNS
somatic, autonomic
somatic NS
sensory and motor functions
autonomic NS
controls glands, organs, muscles
descriptive research
allows us to systematically and objectively observe and describe what we observe
does not answer WHY –> cannot draw conclusions about cause and effect relationships
advantages of a case study
keep a record of very rare cases that could be lost otherwise
most in-depth research you can do
1st step when researching something you know nothing about
disadvantages of a case study
- researcher bias
- cannot draw general conclusions
- cannot generalize findings to general public
- single person being studied may be atypical
survey
can be part of descriptive and correlative research
results of a survey must be representative of population of interest or it has no scientific value
response bias
number of factos that could lead subjects to answer inaccurately
ex.
- acquiescence bias
- social desriability bias
- volunteer bias
- illusory superiority
acquiescence bias
tendency for subject to agree with whatever the researched is asking
social desirability bias
subjects do not give an honest answer because they want to be perceived in a positive light
volunteer bias
volunteers may not be representative of the population of interest
illusory superiority (self-serving bias)
tendency for most people to perceive themselves as better than average
correlational research
purpose is to observem describe, and make predictions
help us determine if there is a systematic and reliable relationship between 2+ variables
positive correlation
variables change in the same direction
negative correlation
variables change in opposite directions
3 major questions of correlational research
1) do they covary (have a relationship)
2)in what direction?
3) how strong is the relationship?
correlational research coefficient (r)
value varies from -1 to +1
- minus is negative correlation
- plus is positive correlation
- 0 is no relationship at all
disadvantages of correlational research
we cannot infer causality
experimental research
the only was to define a cause-and-effect relationship
BC the researchers manipulate the independent vairable
field experiment
experiment in the real world
random assignment
every subject in the study has equal chance of being the experimental or control group
descriptive statistics
collection of ways to desribe data in the simplest way possible
QUANTITATIVE VALUES
central tendency
the score that best represents the others
3 kinds:
- mean (most commonly used)
- median
- mode
what is the disadvantage of using mean (average)
heavily influenced by extreme numbers
