Sense and Perception Flashcards
1
Q
Sensation
A
simple stimulation of a sense organ
2
Q
perception
A
the organization, identification, and interpretation of a sensation in order to form a mental representation
3
Q
transduction
A
when sense receptors convert signals from the environment into neural signals that are sent to the CNS
4
Q
psychophysics
A
methods that systematically relate the physical characteristics of a stimulus to an observer’s perception
5
Q
acuity
A
how well you can distinguish between two similar stimuli
6
Q
sensory adaption
A
sensitivity to a stimuli decreases over time
7
Q
Purity (light)
A
the degree to which a light source is emitting just one wavelength, or a mixture of wavelengths
8
Q
What do bipolar cells do in the eye?
A
Bipolar cells collect electrical signals from the rods and cones and transmit them to the outermost layer of the retina
-From there neurons (retinal ganglion cells (RGCs)) organise them and send them to the brain
9
Q
What is the optic nerve made of
A
The optic nerve is made of RCGs, and contains no photoreceptors (blind spot)
10
Q
Which area of the brain do visual signals get sent?
A
Visual signals are first sent to the lateral geniculate nucleus (LGN) in the thalamus of each hemisphere.
From there, the visual signals go a location called area V1 (the part of the occipital lobe that contains the primary visual cortex)
11
Q
What are the 2 visual pathways
A
Ventral (lower) stream
- the “what” pathway
The dorsal (upper) stream
- the “where” pathway
12
Q
Binding problem
A
how the brain links feature together so that we can see unified objects in our visual world rather than free floating or miscombined features
How do we see the world as a seamless whole?
13
Q
Sound Waves
A
changes in air pressure unfolding over time
14
Q
Frequency (sound)
A
perceived as pitch
15
Q
Amplitude (sound)
A
perceived as loudness (the perception of a sound’s intensity)
16
Q
Complexity (sound)
A
Affects timbre
17
Q
Timbre
A
the quality of sound that allows you to distinguish two sources with the same pitch and loudness (ex. The difference between a clarinet and oboe playing the same song in the same key)
18
Q
Outer ear
A
Collects and funnels sound
-Pinna
-Auditory canal
-eardrum
19
Q
Middle ear
A
Transmits and amplifies sound
Ossicles
-Hammer “malleus”
-Anvil “incus”
-Stirrup “stapes”
Pushes against the oval window
20
Q
Inner ear
A
Transduces sound into neural impulses
-Cochlea (“snail”)
-Basilar membrane
21
Q
Cochlea
A
Fluid filled tube that contains cells that transduce sound vibrations into neural impulses
22
Q
Basilar membrane
A
A structure in the inner eat that moves up and down in time with vibrations relayed from the ossicles, transmitted from the oval window
Sound causes the basilar membrane to move up and down in a travelling wave
23
Q
Inner hair cells (ears)
A
Specialized auditory receptor neurons embedded in the basilar membrane
Bends back and forth in cochlear fluid, generating rhythmic action potentials in auditory nerve axons
24
Q
Where do auditory signals go?
A
Auditory signals are sent to the thalamus and ultimately to an area of the cerebral cortex called area A1 (the primary auditory cortex in the temporal lobe)
25
Where are spacial auditory features handled in the brain?
Spatial auditory features are handled by areas towards the back of the temporal lobe in regions that may overlap with the visual dorsal stream
26
Where are sound identification features located in the brain?
Sound identification features are handled by areas in the lower (ventral) part of the temporal lobe (may overlap with the ventral visual pathway)
27
How do you detect Loudness
Signalled by total amount of activity in hair cells
28
How do you detect pitch
Seems to depend on two factors
First, different frequencies stimulate different parts of the basilar membrane
This provides a place code
The brain uses information about the relative activity of hair cells across the whole basilar membrane to help determine the pitch you hear
Second, the hair cell hairs move in time with the incoming sound wave, so auditory nerve axons fire synchronously with the sound-wave peaks, which happen regularly at the sound’s repetition rate
-This provides a temporal code
The brain uses the timing of the action potentials in the auditory nerve to help determine the pitch you hear
29
How do you detect Timbre
partially depends on the relative amounts of different frequency components in a sound, (depends on the relative activity of hair cells across the whole basilar membrane)
30
How do you detect location of sound
Has both one ear (monaural) cues and two ear (binaural) cues
-The pinna folds alter sound, emphasising some frequency components over others based on where they came from
-The speed of sound is relatively slow, the brain can interpret small time delays to judge distance
-Higher frequencies are more intense close to the ear than further away, as your head can block the sound
31
Perceptual grouping
figuring out which frequency belongs together in a single source
32
Perceptual Segregation
figuring out which frequency components belong to different sources
33
Conductive hearing loss
the eardrum or ossicles are damaged to the point where theory cannot conduct sound waves effectively to the cochlea
-The cochlea is normal
Medication or surgery are often a solution
-Hearing aids can improve hearing
34
Sensorineural hearing loss
damage to the cochlea, the hair cells, or the auditory nerve
-Happens to almost all of us when we age
-Sensitivity decreases (sounds must be more intense to be heard)
-Acuity decreases - sounds smear together on the basilar membrane
-Makes voices harder to understand
35
Haptic Perception
the active exploration of the environment by touching and grasping objects with our hands
36
Tactile Receptive Field
A small patch of skin that relates information about pain, pressure, texture, patter, or vibration to a receptor
37
Thermoreceptors
nerve fibres that sense cold and warmth, respond when your skin temperature changes
38
A-delta fibres
axons that transmit initial sharp pain
-fast acting
39
C-fibres
axons that transmit the longer lasting, duller persistent pain
-slower
40
What are the two pain pathways
One sends signals to the somatosensory cortex, identifying where the pain is occurring and what type of pain it is
The other sends signals to the motivational and emotional centres of the brain, such as the hypothalamus and amygdala, as well as to the frontal lobe
-Makes pain unpleasant and motivates us to escape from it
41
Can your pain sections of the brain get activated by other's pain?
Your pain sensing part of the brain (especially the frontal lobe) also responds when you see other people in pain
42
Social Pain
embarrassment or social exclusion
43
Referred Pain
when sensory information from internal and external areas converges on the same nerve cells in the spinal cord
Ex. heart attack
-People feel pain from their left arm rather than from inside the chest
44
Is the severity of an injury a reliable measure of pain intensity?
Pain intensity cannot be determined solely by the severity of the injury that inflicted it
45
Gate control theory
signals arriving from pain receptors in the body can be stopped by interneuron in the spinal cord via feedback from the skin of from the brain
46
Can your brain control your level of pain?
Under high stress conditions the brain can send signals to the periaqueductal grey (PAG) in the spinal cord to suppress pain signals
The brain can also increase the pain you feel
-This is the theory for why being sick is painful, its the bodies way of forcing you to rest
47
Proprioception
your sense of body position
48
Where do you get info about position of torso and limbs
Info about position of torso and limbs depends on stimulation of receptors in the muscles, tendons, and joints of the body
49
Where do you get info about where is up and down and head position
Info about where is up and down and head position is regulated by the inner ear
50
Vestibular system
the three fluid-filled semicircular canals and adjacent organs located next to the cochlea in each inner ear
51
How does your ear gather info to send to the vestibular nerve
Hair cells are throughout the semicircular canals and their movement generates activity in the vestibular nerve that is conveyed to the brain
52
What causes motion sickness
Mismatch between visual and vestibular information leads to motion sickness
53
Olfaction
Smell
54
Where does olfactory information go to in the brain
Skips the thalamus
Heads to the frontal lobe, amygdala, hippocampus, and other forebrain structures directly
-This suggests that smell has a close relationship with areas involved in emotional and social behaviour, as well as memory
55
Odorant molecules
chemicals that stimulate smell
56
Olfactory Epithelium
a mucous membrane along the top of the nasal cavity
-Contains 10 million olfactory receptor neurons (ORNs)
57
Olfactory receptor neurons (ORNs)
receptor cells that transduce odorant molecules into neural impulses
58
Olfactory Bulb
A brain structure located above the nasal cavity beneath the frontal lobes
59
Pheromones
biochemical odourants emitted by the members of an animals’ species that can affect its behaviour of physiology
-Plays an important role in reproductive and social behaviour
60
Do humans have pheromones?
Mayhaps
-People stink more during puberty
-Breastfeeding mothers and babies
Repeatable research is hard to do for this
61
Where did taste evolve from
Smell
62
Is how you taste learned or genetic
Both
63
What are the types of tase receptors
-Salty
-Sour
-Bitter
-Sweet
-Umami (savory)
64
Papillae
The small bumps on the tongue
-Contains hundreds of taste buds
65
Taste buds
the organs of taste transduction
-Each contains 50 to 100 taste receptors
-The tips are called microvilli (they react with tastant molecules in food)
66
How many taste buds are in the human mouth?
5000 to 10000
67
What is the sixth taste type
oleogustus (fat)
68
Taste
The signals picked up by the tongue
69
Flavour
the combination of the signals being picked up by the tongue and nose, interpreted by the brain
70
Can environmental factors have an effect on flavour
yes
71
Parallel Processing
The ability to attend to many sense modalities simultaneously
72
Bottom up Processing
Constructing a whole stimulus form individual parts
73
Top Down Processing
Conceptually driven processing influenced by beliefs and prior learning
74
Perceptual Set
A set formed when expectations influence perceptions
75
76
Perceptual Constancy
The process by which we perceive stimuli consistently across varied conditions
Includes shape, size, colour, ect
77
Selective Attention
We can study on some things to the exclusion of other things
Associated with the reticulate activation system (RAS) and the higher cortical regions
78
The filter theory of attention
Attention is a “bottleneck” through which information passes
You can’t pay attention to multiple things at once
79
Dichotic Listening
subjects wear headphones where two different messages are played to different ears
Which ear do you listen to?
80
Inattentional Blindness
Failure to detect stimuli what are in plain sight when our attention is focused elsewhere
"gorilla in basketball game"
81
Change Blindness
Rapidly changing pictures make it hard to see differences between them
82
Subliminal messaging
The idea that you can change a person’s behaviour by showing them stimuli that change someones behaviour
-Not scientific, but widely believed
-Fears of this led to parental advisory warnings
83
Extrasensory Perception (ESP)
Perception of events outside the known channels of sensation
-not scientifically backed
Is there a way to perceive things outside of conventional means? (sight, hearing, ect.)
84
Precognition
Predicting events before they occur though paranormal means
Ex. what card will appear
85
Telepathy
Communication between minds
-mind reading
86
Clairvoyance
Detecting the presence of objects or people hidden from view
Ex. what card someone is holding
87
Ganzfeld Technique
Cut the “receiver” off from environmental noise to allow people to feel only extrasensory stimuli
-Ping Pong balls on eyeballs and only red light?
-Safe, but useless
-Only has an effect if you believe it will have one
88
Why do people believe in ESP?
⅔ of Americans claim to have psychic experiences
Illusory Correlations
-We dwell on coincidences
We don’t update internal correlations
People underestimate the frequency of coincidences
-People think things are more or unusual then they think
-Eg. The Birthday coincidence (in a room of 25 people, there is a 50% chance that two people share a birthday)
89
Visible Light
Electromagnetic radiation from 400 - 700 nanometers (in humans)
90
Hue
Colour of light
91
Brightness
he amount of reflected light that reaches the eye
92
Pupillary reflex
Controls the amount of light allowed into the eyes
-Pupils also widen when you’re interested
93
Cornea
Transparent cover of the eye
-Shape of this decides if you're nearsighted (myopia) or farsighted (Hyperopia)
94
Myopia
Nearsightedness
-Cornea is too big
95
Hyperopia
Farsightedness
-cornea is too flat
96
Lens (eye)
hard-ish substance that bends light toward retina
-Can adjust its shape (accommodation)
97
Retina
Receives light and converts it to neurological activity
98
Rods (eye)
Lets you see low levels of light
-Does not see colour
-~92 million per eye
-Does not function instantly (takes time to adjust) (dark adaptation)
-Concentrated outside of fovea (peripheral vision)
-Not great at seeing detail
99
Cones (eye)
Lets you see colour
-Also lets you see detail
-~6-7 million per eye
-Concentrated in the fovea (fovea centralis)
100
Photopigments
protein molecules that absorb light and trigger a biochemical cascade that alters the electrical properties of photoreceptors
101
Optic Nerve
Nerve (technically a bundle of ganglion cell’s axons) that travels from the retina to the brain
-Eventually reaches the optic chiasm
-Left vision goes to the right brain, right vision goes to the left brain
Creates a blind spot
102
Feature detection cells
cells that detect lines and edges
-At later levels of visual processing (e.g. V2) cells begin to detect more complex shapes and movements
103
Gestalt Psychology
Emphasises the natural organisation of perceptual elements into wholes or patterns
-The whole is greater than the sum of its parts
-Psychology would focus on how the whole is created from the parts
Gestalt = Whole
104
Proximity
Objects physically close to each other tend to be perceived as unified wholes
105
Similarity
similar objects will be seen as being grouped together or related
106
Continuity
We perceive lines as continuous movement while discounting abrupt changes
107
Closure
Incomplete forms will be seen as complete objects
108
Symmetry
Symmetrically arranged objects are perceived as wholes
109
Figure-ground segregation
The tendency to separate elements of an image into a foreground and background
110
Trichromatic Theory
Vision is based around primary colours;
-Red
-Green
-Blue
Fits with later findings that there are three types of cone cells that respond to different wavelengths of light
-Short (S-cones)
-Medium (M-cones)
-Long (L-cones)
Relies on additive colour mixing
CON - Can’t account for afterimages
111
Opponent Process Theory
Theory that we perceive colors in terms of three pairs of opponent colours
-Red to green
-Blue to yellow
-Black to white
Afterimages correspond to the complementary colour on the colour wheel
Retinal Ganglion cells are activated when one colour is shown, but inhibited for others
112
Dual Process Theory
A modern colour vision theory that combines trichromatic and opponent process theory
113
Colour Blindness
Inability to see some or all colours
-Usually due to genetic abnormalities
Monochromats - have only one type of cone (very rare
Dichromats - have two types of cones
Brain damage to cortical areas are responsible for vision can also produce colour blindness
114
Depth Perception
The ability to judge distance and three dimensional relations
115
What are the monocular cues of depth perception (There are 7)
Relative size
-More distant objects look smaller
Texture gradient
-The farther away something is, the less detail it has
Interposition
-A close object will block a far object
Linear perspective
-The outlines of objects converge at distance increases (hallway closing to a point)
Height in plane
-Nearer objects appear lower, further objects appear hight
Light and shadow
-The casting of shadows fives objects a 3D form
Motion parallax
-Closer objects appear to move faster than further objects
- Can give an impression of motion of an object that is actually stationary
116
Binocular cues of depth perception
Binocular Disparity
-Depth information is obtained by comparing the difference in image location of the left and right eyes
-The further away, the bigger the difference between eyeballs
Binocular Convergence
-Objects that are nearby are going to be reflexively focused on by turning in
-Your brain keeps track of the eye angle
117
Blindness (vision loss)
The inability to see
-Vision is less then 20/200
Many different causes
-Glaucoma
-Cataract
-Diabetic retinopathy
-Childhood blindness
-Macular degeneration
Problems with visual receptors
You can have it in many different degrees
-Continuity
Blind people tend to rely more on other senses
-Visual cortex function changes due to neural plasticity
118
Motion Blindness
A neurological disorder in which a person is not able to perceive motion
Also known as “ Cerebral Akinetopsia”
Often caused by brain damage or Alzheimer's disease
119
Visual Agnosia
A failure to recognise visually presented objects
Not due to memory problems or intelligence
Often due to damage to peripheral regions fo occipital cortex neat the perinatal lobes
Many types
Ex. Prosopagnosia (inability to recognize faces)
120
Blindsight
The ability of individuals with blindness to detect and respond to visual stimuli despite lacking awareness of having seen anything
-Often the result of damage to V1 area of visual cortex
They can see but can't see
121
How do you measure the just noticible difference?
**Weber's Law**
JND = K x I
I = Intensity
K is a constant that is measured by conducting measurements on a subject
