sensation and perception recap Flashcards
vision: stimulus, receptor, sensory structure, cortex
electromagnetic energy, photoreceptors, eye, primary visual cortex
hearing: stimulus, receptor, sensory structure, cortex
air pressure waves, mechanoreceptors, ear, auditory cortex
touch: stimulus, receptor, sensory structure, cortex
tissue distortion, mechano/thermoreceptors, skin/muscle, somatosensory cortex
balance: stimulus, receptor, sensory structure, cortex
gravity/acceleration, mechano, vestibular organs, temporal cortex
taste/smell:stimulus, receptor, sensory structure, cortex
chemical composition, chemo, nose/mouth, primary taste cortex/olfactory cortex
perception map
stimulus in enviro—> light reflected and focused—> receptor processes (transduction, transmutation/processing)—-> neutral processing—> perception<_---> recognition<---> action</_--->
perception and recognition
I see something and its an oak tree!
transduction is when…
individual sense organs transduce energy from env event –> neural activity (nerve impulses)
how does transduction occur?
because sense organs have specialised receptors
transduction simplified
environmental energy–> receptors–> nerve impulses
transmission
carries signal from receptors to brain and around brain, 1 neuron activates next
processing
electrical energy processed through network of neurons
bottom- up processing
data based- based on incoming stimuli from environment
top-down processing
knowledge based- based on existing info/previous knowledge
3 approaches to study of perception:
1) PP, PSYCHOPHYSICAL APP
2) PH 1, PHYSIOLOGICAL APP
3) PH2, PHYSIOLOGICAL APP
1- stimulus-> perception
2- stimulus-> physiology
3- physiology-> perception
neuroanatomy
structure and connectivity of nervous system
neurophysiology
how neurons work and communicate
peripheral NS
2 parts:
somatic= controls voluntary muscles (biceps) and transports sensory info to CNS
autonomic= controls involuntary muscles (heart/ digestion)
within autonomic NS (involuntary)
2 systems
sympathetic NS- speeds up
parasympathetic NS- slows down
recap of NS
NS:
1- CNS—-> brain and spine
2- PNS –>
- somatic
- autonomic has…
(sympathetic and parasympathetic NS) for involuntary processes like digestion.
the cerebral cortex divides into 4 brain lobes located…
frontal (top left)
parietal ( top right
temporal (bottom left)
occipital (bottom right)
where each cortex is in the brain lobes
cerebrum divided into 2 hemispheres
left H- controls right part of our body
right H- controls left part of our body
frontal lobe
personality, speech, problem solving and movements ( primary motor association cortex)
temporal lobe
sound and memory ( auditory association cortex)
parietal lobe
touch, temp and pain ( somatosensory association cortex)
occipital lobe
vision ( visual association cortex)
quick recap
lobe and cortex
- frontal
- temporal
-parietal
- occipital
f- motor
t- auditory
p- somatosensory
o- visual
cerebellum
balance, coordination and motor movement
brain stem functions
breathing, swallowing, sneezing, coughing, heartbeat
in middle of brain the pituitary gland produces
hormones that control growth, and production of sperm and eggs
2 lobes
anterior - growth, reproduction, testosterone prod, thyroid (metabolism)
and posterior- oxytocin (childbirth and lactation) and vasopressin (urine)
hypothalamus controls release of these hormones
in the middle of the brain the pineal gland produces…
hormone melatonin (sleep)
CNS Dif parts of the brain
forebrain
midbrain
hindbrain
forebrain: voluntary
1. thalamus
2. hypothalamus
3. cerebral cortex (4 lobes)
4. limbic system
5. corpus callosum
midbrain: involuntary
hindbrain: involuntary
1. cerebellum
2. pons
3. medulla
the ‘c’s’
cerebral cortex
cerebellum
cerebrum
the cerebral cortex is the OUTER LAYER of the cerebrum big part of the brain with all four lobes the CC is the majority of the forebrain
the cerebellum is part of the Hind brain, the lump at the bottom in control of motor mov, balance…
the cerebrum consists of two cerebral hemispheres the outer layer called the cerebral cortex (gray matter- 4 lobes) and the inner layer (white matter).
the white matter contains many nerves (axons) that exchanges info and communicates info to Dif parts of the brain
- its called white matter because the axons are covered in myelin shieths ( to speed up conduction) which are white
functions of the forebrain
thalamus
hypothalamus
cerebral cortex
limbic system
corpus callosum
thalamus - in each cerebral hemisphere ( left and right side of brain) is the RELAY CENTRE…. as info comes up spine goes to thalamus first and then onto the cortex ( 4 lobes) has lots of Dif specialised nuclei for Dif sensory info.
hypothalamus- left and below of thalamus (pituitary gland is attached to left and below of hypo (v small))- HOMEOSTASIS AND HORMONES and CONTROLS AUTONOMIC NS ( symp and para) , manipulates hormone release by controlling pituitary gland “master gland”
cerebral cortex- outer layer of cerebrum which has the 4 lobes
limbic system- has amygdala ( emotions) and hippocampus ( LTM)
corpus callosum- allows info to transmit from one side of the brain to the other
function of the hind brain:
cerebellum
pons
medulla
cerebellum- control coordination and balance
pons - part of brain stem, links brain to spine, unconscious processes like sleep breathing etc.
medulla oblongata- bellow pons in brain stem, cardiovascular and respiratory systems
nerves and job
olfactory
optic
oculomotor
smell
vision
eye mov
what determines how much of the cortex is devoted to a function?
the complexity the task
neuron
soma
dendrite
axon
terminal button
synapse
myelin shieth
glial cell
node of ranvier
celll body
receives info from other neurons
carries info from soma to terminal buttons
forms synapses and sends info to next neuron
junction - synaptic transmittion
insulating - forms white matter
a cell that makes myelin sheaths
naked portion of axon, speeds up conduction , located between glial cells
damage to myelin sheaths can cause problems like…
multiple sclerosis (MS)
neurons are surrounded by solution of ions…
sodium
chloride
potassium
positive
neg
positive
action potential
- D
- AP
- R
- H
depolarisation- na channels open, na enters and locally depolarises axon, which further depolarises the adjacent (next to) region to open more na channel, K also enters - MAKING MORE POSITIVE
3- na close and k remain open for a bit, k then shut
4- refractory period state of recovery t keep unidirectional flow
synaptic transmission
NT released by vesicles in preS N
received by postS memb on receptor sights
lock and key
change in voltage - AP
2 types of NT
excitatory
inhibitory
e= cause depolarisation
neuron becomes more positive
increase likelihood of AP
-= cause hyperpolarisation
neuron becomes more negative
lower chance of AP
visible light is a specific band of energy within….
measured in …
the electromagnetic spectrum
wavelength ( the Dif between the peaks of the waves ) nm
dopamine function
malfunction
mov, motiv, emotional pleasure and arousal
high levels = scitzophrenia
low levels= Parkinson’s/ tremors
glutamate function and enzyme
malfunction
major excitatory NT- learning and memory
glutamate dehydrogenase
oversupply= migraines or seizures
gamma- aminobutyric acid (GABA) function and enzyme
malfunction
primary inhibitor neurotransmitter
GABA transaminase
undersupply= anxiety tremors
noradrenaline function and enzyme
malfunction
mood and arousal
monoamine oxidase
undersupply= depression
serotonin function and enzyme
malfunction
hunger sleep arousal/agression
monoamine oxidase
undersupply= depression
endorphins function and enzyme
malfunction
emotions
lack of= lower pay threshold
ST- occurs as long as NT is in synapse
3 ways to stop synaptic transmutation
reuptake
pre-synaptic auto-receptor ( vesicle stops releasing NT)
enzymatic degration - NT broken down by enzymes
agonistic drugs increase the …
and block…
morphine, heroin basically and painkillers
synthesis of NT
release of NT
block inhibitory effect on presynaptic receptors ( so they stay in synapse)
block reuptake of NT ( so stay in synapse)
activate the post synaptic receptor
antagonistic drugs block…..
and….
synthesis of NT
release of NT
destroy NT in synapse
block NT binding to post synaptic membrane
short wavelength =
long wavelength =
visible to humans range =
gamma rays
radio waves
400-700nm
how is an image formed, what work together??
the lens and the cornea are optical components, together they form an inverted image on the retina (back of eye)
cornea = 80%
lens= 20%
def of eye parts:
cornea=
scelera=
iris=
lens=
transparent tissue at front of eye
tough white tissue that coats the rest of the eye
muscle that controls the size of the pupil and so amount of light that enters the eye
bends incoming light
accommodation occurs when we adjust eyesight to see things in Dif distances… by..
the ciliary muscles tighten causing the lens to thicken and bend light more, to focus on nearby objects
optical problems:does… caused by.. corrected by
myopia or nearsightedness, refractive vs axial
hyperopia or farsightedness
m- can’t see things far away, refractive= cornea or less bend too much light, axial= eyeball is too long
h- can’t see close things clearly, eyeball too short
the near point is the distance where…
presbyopia (old age)…
the lens can no longer adjust for close objects
distance increases with age due to hardening of lens and weakening of ciliary muscles.
photoreceptors in the eye =
outer layer of them contains ….
visual transduction occurs when…
retinal changes chape in a process called…
rods and cones
rhodopsin - opsin (protein) and retinal (light sensitive mol)
the retinal absorbs light
isomerization
blind spot is the place where…
the optic nerve leaves the eye , the brain fills in the spot
fovea is the part of the retina which provides our
it has the most…
peripheral retina=
periphery=
highest acuity vision
cones
rods and cones
rods>cones
rods allow us to see in …..
cones allow us to see in …
in light but no colour
colour under normal light conditions
rods to ganglion cell
cones to ganglion cell
ratio
more rods, less cones so cones give more resolution so can see in dark
rods are more sensitive to light so…
they take less light to respond which is why they can see in dim light
when visible light falls on an object it is either …… (solid objects) or ….. (transparent objects)
reflected…. transmitted
wavelengths
short
medium
long
long and medium
long medium and short
blue
green
red
yellow
white
rod photo pigment absorbs best at ….
cone pigments absorb best at ….. short, ….. middle, … long known as the…
500nm
419 ( blue), 532 (green), 558 (red) —- trichchromatic theory of colour vision - sermon von Helmholtz
the opponent-process theory of colour vision by….
ewald hering
