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PSYC 2390 Midterm 1 > Lecture Set 1 > Flashcards

Lecture Set 1 Flashcards

1
Q

What is transduction?

A

changing energy from 1 form to another

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2
Q

What systems make up a human’s nervous system?

A

electrical and light energy

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3
Q

What is involved in the electrical system?

A

electrical impulses to send information

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4
Q

What is involved in light energy system?

A

form of electromagnetic radiation (range of wavelengths)

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5
Q

What is distal stimulation?

A

Light that reflects off an object at a distance

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6
Q

What is one of the first things to do in regards to vision?

A

Converting light to electricity

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7
Q

What is proximal stimulation?

A

Light being shone on back of eye (retina)

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8
Q

What do humans respond directly to in terms of vision?

A

Not directly to distal stimulation but light that directly hits the back on the eye

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9
Q

What systems make up hearing?

A

mechanical and electrical

- more complicated than vision

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10
Q

What is interpretation?

A

Determining what a pattern of electrical signals means

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11
Q

What can be used to demonstrate interpretation?

A

Illusory contour

- energy isn’t changing but interpretation is

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12
Q

What is the nervous system?

A

system used for communication

- taking information from one place to another

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13
Q

What makes up the neutron?

A

cell body (nucleus), dendrites, axon, myelin

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14
Q

What is the role of dendrites?

A

receive information

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15
Q

What is the role of the axon?

A

very important for transmission of information (sending information)

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16
Q

What does the width of an axon determine?

A

The size of axon determines how quick an electrical impulse travels (speed)

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17
Q

How does body prioritize sensory information?

A

Motion = really fast

Fine detail = not so important

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18
Q

When does information move the fastest through an axon?

A

The larger it is

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19
Q

Two factors affecting speed of electrical impulse?

A
  1. width of axon

2. myelin

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20
Q

Which species’ electrical impulse is only affected by the width of an axon?

A

Invertebrates (contain no backbone)

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21
Q

Which species’ electrical impulse is affected by axon width and myelination?

A

Vertebrates (contain backbone)

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22
Q

What is the function of myelin sheath?

A

speeds up impulse

- current jumps from one point/node to another rather than travelling entire axon

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23
Q

What is the cause of multiple sclerosis?

A

myelin deterioration

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24
Q

What are outcomes associated with multiple sclerosis?

A

trouble sending neural messages

- motor and perceptual problems

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25
Q

Are babies born with myelin?

A

Yes, but in small amounts

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26
Q

What is the reason babies lack motor function?

A

Lack of myelin

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27
Q

Myelination in babies grows in what pattern?

A

From the head to the toes

- central to periphery

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28
Q

What make up everything in the world?

A

atoms

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29
Q

positive charge in atoms is associated with?

A

protons

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30
Q

negative charge in atoms is associated with?

A

electrons

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31
Q

neutral charge in atoms is associated with?

A

neutrons

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32
Q

Which charges are found inside the nucleus?

A

protons and neutrons

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33
Q

Where can electrons be found?

A

floating around the nucleus

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34
Q

What differs between elements?

A

number of protons, which is equal to number of electrons

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35
Q

What is an element?

A

pure form

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36
Q

What is known as a mixture of atoms?

A

compound

e.g. NaCl

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37
Q

What is an ion?

A

a charged particle

e.g. Na+ or Cl-

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38
Q

What is electricity?

A

movement of ions or changed particles

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39
Q

What is known as the fluid inside the cell?

A

intracellular fluid

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40
Q

What does the intracellular fluid contain?

A

Amino acid ions (molecule with a negative charge)

- occasional potassium ion

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41
Q

What is known as the fluid outside the cell?

A

extracellular fluid

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42
Q

What does the extracellular fluid contain?

A

full of sodium ions

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43
Q

What is known as the skin of the axon?

A

the membrane

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44
Q

What is one characteristic of the membrane?

A

selectively permeable

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45
Q

What does it mean to be selectively permeable?

A

blocks some things out but lets some things in

- blocks sodium, keeps potassium and amino acids in

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46
Q

How is activity recorded in a single neuron?

A

using a voltmeter which is hooked up to a computer that creates a graph

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47
Q

What is the graph created by a voltmeter known as?

A

oscilloscope trace

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48
Q

What does an oscilloscope trace demonstrate?

A

membrane potential (milli volts vs time)

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49
Q

What is membrane potential?

A

measure of charge on the inside of membrane compared to the outside

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50
Q

How can a neutron be stimulated?

A

electrical impulse, pressure, chemical or heat

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51
Q

What happens when a neutron is stimulated?

A

membrane changes its permeability

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52
Q

What is the first stage of an action potential?

A

sodium rushes in to intracellular membrane (membrane potential = +40 mV)

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53
Q

What is the second stage of an action potential?

A

doors close and potassium gets booted out of intracellular membrane (shoots a bit below -70mV)

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54
Q

What is an action potential?

A

after stimulation, when sodium rushes in and then potassium leaves

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55
Q

What happens during the recovery period?

A

The resting potential returns to normal

- the neuron is doing everything it can to get things back to the way it started

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56
Q

What is the role of the Na/K pump during the recovery period?

A

throws sodium back to extracellular fluid and brings potassium back to intracellular membrane

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57
Q

What is the maximum number of action potentials most neurons can undergo?

A

500 per second

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58
Q

Explain a propagated response in unmyelinated axon

A

In invertebrates, action potentials occur along axon in a sequence only moving forward, on after another

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59
Q

Explain a propagated response in myelinated axon

A

In vertebrates, exchange of ions only occur at the point between the bubbles of myelin

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60
Q

What is saltatory conduction?

A

The current jumps from one point to another (faster process)

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61
Q

What is spontaneous activity?

A

when you have axons in a living organism, sometimes you get certain number of action potentials per second even without stimulation (each cell has a baseline for spontaneous activity)

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62
Q

What is post-synaptic transmission?

A

Electrical charge causes these vesicles to migrate to the end and some of them will release there neurotransmitter through the gap where is it picked up by another dendrite

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63
Q

What are the two types of neurotransmitters?

A

excitatory or inhibitory

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64
Q

What are excitatory neurotransmitters?

A

increases probability that the receiving neutron will have an action potential (fork ending)
- increase number of action potential per second

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65
Q

Example of excitatory neurotransmitter?

A

Acetylcholine

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66
Q

What is acetylcholine’s role?

A

used to send messages from neuron to muscle –> contraction

- including the heart

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67
Q

What effect can black widow venom have on the body?

A

Can cause a flood of ACh –> muscle convulsions

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68
Q

What happens when excitatory neurotransmitters?

- for example, with the use of carare

A

Causes immediate paralysis

- enough can stop the heart

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69
Q

Which neurotransmitter is involved in perception?

A

Glutamate

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70
Q

What are inhibitory neurotransmitters?

A

reduce the probability that the receiving neutron will have an action potential (flat line ending)

  • decreases the number of action potentials per second
  • no effect on non-living organisms (must have spontaneous recovery)
71
Q

What is a common inhibitory neurotransmitter?

A

GABA

- associated with sedatives and sleeping pills

72
Q

Effect of valium or barbiturates on the body?

A

slows down the rate of neural firing

73
Q

What are linear circuits?

A

occurs when you have one neuron that is connected to another (excitatory, inhibitory or both)
- associated with just one neural synapse

74
Q

What are converging circuits?

A

occur when two or more different neural synapses are connected to a third

75
Q

Who discovered psychophysics?

A

Gustav Fechner

- philosopher physicist

76
Q

What did Gustav Fechner discover?

A

the relationship between the physics of stimulus (external) and (internal) psychological reactions
- perceiving something vs. not perceiving something

77
Q

What is the absolute threshold?

A

the weakest stimulus that can be perceived

78
Q

What is the effect of smoking on threshold?

A

tobacco, nicotine –> increases threshold = decreases sensitivity

79
Q

What is the effect of alcohol on threshold?

A

increases all taste thresholds (especially bitter)

80
Q

What is the effect of aspirin on threshold?

A

increases threshold for sound = decreases sensitivity (deafness)

81
Q

What is the effect of sex hormones (esp. estrogen) on threshold?

A

reduces threshold to smell (women have better sense of smell)

82
Q

men vs. women vision

A

daytime - men have lower threshold and can see better

night - women have lower threshold and can see better

83
Q

How is absolute threshold measured?

A
  1. method of limits
  2. method of adjustment
  3. method of constants
84
Q

Explain the method of limits

A

Involves a series of different intensities of light

  • series of trials, starting with the strongest intensity and then going down the list (descending trial)
  • examine crossover point
  • then perform ascending trial (low to high) and examine crossover point

The different between crossover points is due to expectation

Absolute threshold = an average of both crossover points

85
Q

Explain method of adjustment

A

Intensity dial allowing subject to turn until they stop hearing stimulus (turn down until they can’t hear)

  • still using crossover points
  • very fast, but not that reliable/accurate
86
Q

Explain method of constants

A

Choose between 5-9 consecutive intensities

  • present each the same amount of time but in random order
  • record how many times person perceived it

Threshold = intensity perceived 50% of the time

  • very accurate, but takes a long time
87
Q

How is discrimination measured?

A

By using the difference threshold

88
Q

What are some other names for difference threshold?

A

discrimination threshold = just noticeable difference = differenze limen

89
Q

What is the difference threshold?

A

the smaller different you can perceive

90
Q

What effect does the carbon monoxide involved with smoking have on difference threshold for brightness?

A

higher difference threshold = less sensitive to differences = require larger difference in brightness in order to be detected
- can’t see well at night and in the fog

91
Q

What effect does marijuana and LSD have on difference threshold for colour?

A

increase difference threshold = decrease sensitivity to differences in colour

92
Q

How is difference threshold measured?

A

Method limits/adjustments
- standard and comparison
difference threshold = twice as many crossover points (just noticeable difference more and just noticeable difference less)

Method of constants

  • standard and weight comparison (5-9 intensities)
  • % of the time comparison is judged heavier
  • each weight is presented 100 times in random order

–> negative time error = often when you have two experiences, the more recent thing seems more intense

–> Subjective Equality = 50% of the time heavier, 50% of the time lighter (can’t tell)

Threshold = (intensity judged more intense 75% of the time - intensity judged more intense 25% of the time) / 2
–> averaging just noticeable below and above

93
Q

What is negative time error?

A

often when you have two experiences, the more recent thing seems more intense

94
Q

What is Subjective Equality?

A

50% of the time heavier, 50% of the time lighter (can’t tell)

95
Q

What is Weber’s Law

A

K = JND/standard

The size of JND varies with the size of the standard

  • a small difference is noticeable
  • JND is proportional to standard
96
Q

What is signal detection paradigm?

A

A refinement on the classic psychophysical techniques
- subtle technique allowing us to know 2 different things

Stimulus present - “yes” = hit
Stimulus present - “no” = miss
Stimulus absent - “yes” = false alarm
Stimulus absent - “no” = correct rejection

97
Q

How do you know how sensitive a person is? (in signal detection paradigm)

A

Hits - false alarms

98
Q

What is response criterion?

A

rule for making a decision

99
Q

What is liberal criterion?

A

Not much evidence before they say yes

  • do have some sensitivity but they often have a response bias to yes
  • fake to make senses seem really good
100
Q

What is conservative criterion?

A

require a lot of evidence to say yes

- biased to say no

101
Q

Explain receiver operating curve (ROC)

A

Individual differences between response criterion, but we can make a person liberal or conservative (when money is involved)
- involves 3 different experiments

102
Q

Different payoff matrices involved in ROC

A 
1. liberal
hit = $50
false alarm/miss = -$10
correct rejection = $10
- 99% hits but 90% false alarms
2. conservative
hit = $10
false alarm/miss = -$10
correct rejection = $50
- 14% hits, 5% false alarms
  1. neutral
    same amount for everything or no money at all
    - 70% hits, 61% false alarms
103
Q

ROC - how do you know who is more sensitive?

A

most number of hits (100%) with least amount of false alarms

104
Q

What is signal detection theory?

A

Theory about how we make decisions (whether we perceive things or not)

  • distinguishing between noise and noise + signal
  • make decision based on perceived intensity
105
Q

What is the result of higher perceived intensity?

A

Conservative

  • require more evidence
  • more correct rejections and misses
  • less hits and false alarms
  • vertical line further to the left
106
Q

What is the result of lower perceived intensity?

A

Liberal

  • require less evidence
  • more false alarms and hits
  • less misses and correct rejections
  • vertical line further to the right
107
Q

What are changes in response criteria?

A

changes to perceived intensity (how much evidence is required)

108
Q

How are changes in sensitivity understood according to theory?

A

When distance between 2 peaks is close (a lot of overlap) = low sensitivity

When distance between 2 peaks is far (little overlap) = high sensitivity

109
Q

How does perceived intensity vary as a function of real intensity?

A

Measured by magnitude estimation

- compare two intensities

110
Q

What is response compression?

A

doubling intensity makes it seem less than twice as intense

e.g. light and sounds

111
Q

What is response expansion?

A

doubling intensity makes it seem more than twice as intense

e.g. shock and line length

112
Q

What is Steven’s Power Law and what is it used to describe?

A 
P=KS^n
P = perceived intensity
K = constant
S = physical intensity
n = response compression/expansion (n=1 = completely accurate)
113
Q

n>1 means?

A

response expansion

114
Q

n

A

response compression

115
Q

What is light?

A

electromagnetic radiation

116
Q

What did Newton say about light?

A

stream of particles = photons

117
Q

What did James Clerk Maxwell say about light?

A

Disturbance in electromagnetic continuum which produces a wave

118
Q

What aspects of light can we pick up?

A

Amplitude and wavelength

119
Q

What is amplitude?

A

height of wave from midpoint to top of wave

  • corresponds to brightness of light
  • big = bright
  • small = dim
120
Q

What is wavelength?

A

distance between two wave peaks

  • interpreted by colour
  • long = red
  • short = blue
  • only some electromagnetic radiation is visiable
121
Q

What other forms of electromagnetic radiation is not visible?

A

just beyond - infrared
way beyond - FM, TV, AM
just below - ultraviolet
way below - X-rays, gamma rays

122
Q

What animal can see infrared?

A

snakes

123
Q

What animal can see ultraviolet?

A

insects

124
Q

What must the light do to perceive/see?

A
  1. collect light
  2. focus light
  3. send signal to brain (light–> electrical = transduction)
125
Q

What is the cornea?

A
  • outer surface of the eye
  • tough material
  • clear (to let light in)
126
Q

What is the corneas function?

A
  • let light in
  • protection from outside world
  • aids in focusing (70-80% of light bending)
127
Q

Disorders/problems associated with cornea

A

Corneal disease/injury and astigmatism

128
Q

What is corneal disease/injury

A

Cornea loses transparency (due to infection, trauma, allergies) - light can’t get in

Early signs: halos and rainbows around objects

Repaired through drugs or corneal transplant (using corpse’s cornea)

129
Q

What is astigmatism?

A

Some people are born with misshaped corneas

  • person lacks ability to focus sometimes
  • variable between individuals

Glasses can help to compensate or lasik laser to carve outside of cornea

130
Q

What is the iris?

A

coloured part of the eye

131
Q

What is the pupil?

A

hole in the middle of the iris (black part)

- dilates and constriction

132
Q

What is the pupil’s function?

A
  • capture light

- can change size to control how much or little light gets in

133
Q

What controls pupil dilation?

A

Autonomic nervous system

  • para = calm
  • sym = hype
134
Q

What happens to pupils during sexual attraction?

A

widen

135
Q

What is the effect of belladonna on pupils?

A

causes dilation – cosmetic purposes

136
Q

What is the effect of cognitive work on pupils?

A

dilation

137
Q

Disorders/problems associated with pupils/iris?

A
  1. reduction of pupil size with age = senile meiosis

2. albinism

138
Q

What is albinism?

A

Iris lacks melanin - can see right through and it looks pink (due to reflection of blood vessels)

  • melanin plays a role in protecting eye from receiving too much light
  • often legally blind and have eye tremors
139
Q

Describe the lens

A
  • transparent with yellow tinge (to block out blue light)
  • surrounded by ciliary muscles (help to change shape of lens)
  • gummy bear consistency
  • adds layers with age –> become more densely packed
140
Q

Function of the lens

A
  • capture and let light in

- focus light by changing shape

141
Q

What is accommodation?

A

the visual systems way of adapting to how far away an object is
- important because light rays by nature diverge

142
Q

What happens to the lens with near objects?

A

In order to bend light - bulge lens (short and fat) –> wide array of light angles and bend so that is all focuses in one point at the back of the eye (retina)

143
Q

What happens to the lens with objects at a distance?

A

most of the light misses the eye, so flatten lens –> allows light to focus at back of eye

144
Q

Disorders of accommodation?

A

myopia, hyperopia and presbyopia

145
Q

What is myopia

A

near sightedness

- visual system is specialized for objects that are close

146
Q

Two types of myopia

A

axial and refractile

147
Q

what is axial myopia?

A

some people are just born with elongated eye balls

  • a lot of pace to bend light for near objects
  • but for objects at a distance, the light rays are focused in front of the retina, so by the time it reaches the retina it is out of focus
148
Q

What is refractile myopia?

A

normal shaped eye balls but lens is working too powerfully and bending light too much

149
Q

Cures for myopia?

A

concave glasses
- to broaden light angle out so it comes to focal point at the back of eye

LASIK surgery

150
Q

What is hyperopia?

A

far sightedness

  • experts at seeing things far away but can’t see things close to them
  • cannot bring things that are close into focus
  • cannot bend light enough to make it come to single focal point
  • try to bulge lens but doesn’t bulge enough –> eye strain (ciliary muscles are fatigued)
151
Q

Two types of hyperopia?

A

axial and refractile

152
Q

What is axial hyperopia?

A

flattened out eye ball

- when they are required to bend light a lot, light focuses behind retina

153
Q

What is refractive hyperopia?

A

together, the cornea and lens cannot bend the light well enough when things are close

154
Q

Cure for hyperopia?

A

Convex lenses

  • offing bulge of artificial lens
  • bends light inwards so light focuses at back of eye like its supposed to
  • eye looks large

LASIK surgery

155
Q

What is presbyopia?

A
  • occurs with age
  • lens cells become quite dense and don’t change shape as easily (hard and stiff)
  • silvery muscles get weaker
  • older people have a hard time seeing things close to them
  • nearsighted people can also develop presbyopia, but now they’re near and far sighted at the same time (can’t see anything) = bifocals
156
Q

What happens to the gaining lens?

A

pale yellow –> yellowy brown

  • addition of layers with time
  • the lens not only gets ultraviolet light but also some blue light
  • stop being able to make certain kinds of discriminations between colours
157
Q

What are cataracts?

A

problem with the lens - causing it to become milky coloured

  • can develop with eye disease, trauma, age, or just born with it
  • difficulty seeing –> blindness (interferes with light getting in)
158
Q

How to deal with severe cataracts?

A

removed through phacoemulsification

  • cut into cornea, and take a tube-like things with ultrasound vibrations –> lens disintegrates and is vacuumed out (leaving lens capsule)
  • plastic/silicon lens inserted
  • for some people, this surgery gives them the ability to see ultraviolet light (like insects) - wear yellow tinged glasses because its quite disorienting to see light you’ve never seen before
159
Q

Where is the retina located?

A

very back of the eye

160
Q

What are photoreceptors?

A

the most important thing when it comes to vision

  • receive light
  • perform transduction (light –> electricity)
  • specialized type of neuron
161
Q

What are photo-chemicals?

A

complicated molecules made up of retinol (tiny) and opsin (large)

  • aka photo-pigments
  • when exposed to light –> change colour

Molecule isomerizes –> retinol and opsin break apart –> molecule becomes clear = bleaching

= basis of transduction

162
Q

What is the most common type of photo-receptor?

A

rods

- 120 million per eye

163
Q

What are rods responsible for

A

seeing under low lighting situations

- lack colour vision and details

164
Q

Characteristics of rods?

A
  • very good at capturing light
  • don’t absorb red light
  • take a long time to regenerate
165
Q

Why does it take so long for rods to regenerate?

A

pigment epithelium has the enzymes to do this, but takes some time to put photo-pigments back together
- require vitamin A

166
Q

What photoreceptors make up the fovea?

A

cones

- 5-6 million per eye

167
Q

What is the role of cones?

A

important for fine detail

168
Q

Which photochemicals do cones have?

A

3 different ones:

  • long wavelengths = red
  • medium = green
  • short = blue
  • only take 4 minutes to regenerate
169
Q

What are collector cells?

A

collect electrical messages from rods and cones and summarize information and send to retinal ganglion cells (form of a neuron)
- 126 million rods/cones –> 1 milllion ganglion cells

170
Q

What is the difference between how rods and cones deliver information?

A

rod = a lot of convergence
~120 rods –> ~1 ganglion cell
cones = linear circuits (for fine detail)

171
Q

What is the blind spot?

A

At the back of the eye where all the retinal ganglion cells lead to the optic nerve, no rods/cones
- but the visual system usually fills in information

172
Q

Disorders of the retina

A

detached retina and floaters

173
Q

What causes a detached retina?

A

hard blow to the head
- retina lifts off back of eye –> can’t get to pigment epithelium —> rods and cones get separated and can’t regenerate –> things are always out of focus

  • can use a probe to cause fusing of both surfaces (but never returns to normal)
174
Q

What are floaters?

A

Pieces of tissue or blood in the vitreous jelly –> see little dots

50% middle aged/older people experience floaters
- vitreous humor shrinks and pulls retina away from back of the eye –> little hole in retina –> floating tissue

PSYC 2390 Midterm 1 (3 decks)

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