Seeing and hearing, Lecture 1

?
Is what we perceive the physical truth?
No, it is the mental reconstruction of our environment based on sensory information
1 of 68
What is cognition?
The mental action or process of acquiring knowledge and understanding through thought, experience and the senses
2 of 68
What is Bottom-up processing?
data driven processing as it begins with the stimulus itself, perception directs cognition.
3 of 68
What is top-down processing?
Our behaviour is influenced by conceptual data which constructs our experiences and expectations, perception and behaviour is driven by what we expected to see. Perception is constructed by cognition
4 of 68
What is a psychometric function?
Data taken by observing an observer's performance on a task
5 of 68
What is transduction?
When sensors in the body convert physical signals from the environment into encoded neural signals.
6 of 68
What are perceptual illusions?
The perception of something objectively existing in such a way as to cause misinterpretation of its actual nature
7 of 68
What is prior knowledge?
Knowledge we have prior to an event/seeing something
8 of 68
What is sensory adaptation?
Over time our senses adapt to the environment and do not interrupt the same stimuli as strongly
9 of 68
What is adaptation aftereffect?
After perceiving something one way after a while might cause you to perceive it another way
10 of 68
What are ambiguous figures?
An optical illusion which exploits graphical similarities and other properties of the visual system
11 of 68
What is Bistable perception?
When our perceptual experience continuously alternates when an ambiguous or rivalrous stimulus is observed
12 of 68
What is the Molyneux problem?
The idea that if we regained a sense would we be able to use it straight away?
13 of 68
How does the case studies of people gaining sight after blindness help the molyneux problem?
Shows that people cannot use a sense if they regain it after never having it
14 of 68
What is the case study of Virgil (age 50) of gaining sight after blindness?
They regained sight after cataract surgery but was described as a "mentally blind" person as they could see but could not decipher what was out there
15 of 68
What is the case study of Sidney Bradford (age 52) of gaining sight after blindness?
They regained sight after a cornea transplant. They could not make out perspective in art and pictures and preferred to work with their eyes closed
16 of 68
What is the case study of Helen Keller?
She was deaf and blind at an early age and had no way to learn how to communicate with her seeing and hearing family members, she learned language and eventually speech through the sense of touch with the help of her teacher Anne Sullivan.
17 of 68
What does perception use?
Our sensory inputs
18 of 68
What does the interpretation of our sensory inputs rely on?
Our previous experiences
19 of 68
What type of psychology is seeing and hearing and perception a part of?
Cognitive psychology
20 of 68
What is cognitive psychology?
A study of the internal processes that allow us to perceive, read, speak, attend, remember and think
21 of 68
How can we study cognitive psychology?
Through controlled experiments where we measure behaviour and infer the mental processes behind this behaviour.
22 of 68
When did cognitive psychology emerge and why?
In the 1950s as the dominant approach for understanding the human mind
23 of 68
What is the bottom-up model?
The idea that we perceive a stimulus pay attention to it and think about it come to a decision on what to do and the act upon that decision. Stimulus-> cognition (perception->Attention->thought processes -> decision)-> Response/behaviour
24 of 68
What is the top-down model?
The idea that we see a stimulus however our previous thoughts and experiences influence what we perceive and thus how we act. Stimulus -> perception attention thought processes -> decision -> behaviour
25 of 68
What do visual illusions demonstrate?
That seeing is not just a simple case of detecting light
26 of 68
What was cognitive psychology strongly influenced by?
The development of modern computing
27 of 68
What is the computer metaphor?
The idea that our brain is like a computer they both have information processing, channels, limited capacity, programs/rules/scripts. Stimulus = input, cognition = computation, response = output
28 of 68
What can humans recognise?
Millions of objects and individual faces, even in very poor conditions and with no formal training
29 of 68
When have computers been able to recognise simple, constrained patters?
In the last 10 years
30 of 68
What's better at recognising things, humans or computers?
humans
31 of 68
What is the first stage of information processing?
Perception
32 of 68
What has the cognitive approach influenced and been influenced by?
Human-machine interaction, robotics, computational modelling, artifical intelligence, applied psychology / ergonomics, neuropsychology, cognitive neuroscience
33 of 68
How do we scientifically study perception and cognition?
Psychophysics, cognitive experiments, cognitive neuroscience and neuropsychology, modelling
34 of 68
What is psychophysics?
It uses the objectively defined stimuli and simple, repeated responses to measure the limits of what we can perceive. For example finding out how sensitive we are to contrast
35 of 68
What do experiments in cognitive psychology try to do?
They try to control as many of the different characteristics of the stimulus as possible.
36 of 68
What can we work out by measuring peoples reaction times to stimuluses?
Try to work out the different stages of information processing
37 of 68
What do we need to know about to understand perception?
Sensory stimuli and the sensory receptors of the body
38 of 68
What is sensory transduction?
The process by which the body converts an external stimulus into an action potential
39 of 68
If the sensory modality is vision what is the stimulus, organ and receptors?
Stimulus = light, organ = eye, receptors = rods and cones e.t.c
40 of 68
What does cognitive neuroscience try to do?
Link the stages of perception and cognition to the anatomy and activity of the brain
41 of 68
what does cognitive neuropsychology show?
How damage to different parts of the brain may cause some surprising dissociations
42 of 68
What do our senses do?
Offer a window through which we are able to observe the world
43 of 68
What influences how we see the world?
Our perceptions and our prior knowledge
44 of 68
What is an issue with how we view things?
Sometimes our percept resembles the real thing but sometimes our brain comes up with the wrong idea
45 of 68
What are perceptual illusions?
When our perception cannot make sense of something and gets it wrong
46 of 68
Why do we have perceptual illusions?
Illusions can be a direct result of the physiology of our senses and the neurons processing our sensory information. Illusions can also be learned due to regularities/assumptions about the world.
47 of 68
How is the light from above prior an example of a learned rule?
It relies on our intrinsic knowledge (from experience) that light generally tends to come from above.
48 of 68
What does light from above prior effect?
How we interpret shading on objects
49 of 68
Can we explain all illusions with one mechanism?
No, each illusion has its own explanation based on the physiology and how sensory information is processed (bottom-up) and learned assumptions (priors) involved (top-down)
50 of 68
What are adaptation aftereffects?
Before and after adaptation perception of the same stimulus has changed . Sensory adaption can change our perception of other stimuli of the same kind.
51 of 68
What is sensory adaptation?
The diminished sensitivity to a stimulus as a consequence of constant exposure to that stimulus
52 of 68
What is an example of vision sensory adaptation?
Adjusting to lighting condition when entering a dark room
53 of 68
What is an example of touch sensory adaptation?
Not constantly being aware of the clothes you are wearing
54 of 68
What is an example of hearing sensory adaptation?
We pay less attention to regular sounds (from traffic, fans, clocks)
55 of 68
What is the consequence of sensory adaptation?
We become less aware of the stimulus over time and it changes our perception of other stimuli of the same kind (adaption aftereffect)
56 of 68
What does slant adaption work for?
Both vision and touch
57 of 68
Is perception malleable?
Yes
58 of 68
What is the physiology behind sensory adaptation?
IF a neuron is activated by a stimulus the firing rate decreases over time
59 of 68
What is the physiology behind mechanism motion sensory adaption?
Each neural unit is turned to a particular direction, after a while the output faces the same direction as the gain? (bit confused on this)
60 of 68
Are the actions of others subject to adaption?
Yes, our interpretation changes depending on the actions we have observed before
61 of 68
What is bistable perception?
When there are two percepts for one stimulus and both can't be correct at the same time
62 of 68
What is bistability perception - rivalry?
For some stimuli the two possible interpretations are perceived to rival for awareness
63 of 68
What is the rivalry mechanism? (1/2)
Both interpretation are activated, yet through inhibitory interaction only one interpretation prevails.
64 of 68
What is the rivalry mechanism? (2/2)
However perceptual alternations occur due to wining neurons adapting which leads to a decrease in inhibition over time and the initially suppressed interpretation thus becomes stronger over time.
65 of 68
What account does the rivalry mechanism provide?
A bottom-up account of bistable perception
66 of 68
What are the top-down accounts/influences on bistable perception?
For some figures we do not at first perceive the alternative interpretation if we are not aware it is there. We can influence percept durations by focusing out attention on an interpretation.
67 of 68
To understand perception what do we need to understand?
How the senses work, how they convey information to the brain and how the brain constructs a percept based on the sensory informaiton
68 of 68

Other cards in this set

Card 2

Front

What is cognition?

Back

The mental action or process of acquiring knowledge and understanding through thought, experience and the senses

Card 3

Front

What is Bottom-up processing?

Back

Preview of the front of card 3

Card 4

Front

What is top-down processing?

Back

Preview of the front of card 4

Card 5

Front

What is a psychometric function?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Psychology resources:

See all Psychology resources »See all Visual System resources »