Class Notes (838,272)
Canada (510,817)
Psychology (3,528)
PSY100H1 (1,637)
all (20)
Lecture 7

Lecture 7-1.doc

34 Pages
119 Views
Unlock Document

Department
Psychology
Course
PSY100H1
Professor
All Professors
Semester
Fall

Description
Lecture 7 Using Knowledge Recording 43 Key Themes 1. Mental Representations --> debate of images vs. thought --> visual or verbal 2. Structure vs. Function --> on structure side --> how are our minds organized --> arranged in categories 3. Serial vs. Parallel processing --> access info one at a time or all at once --> how are info organized and connected Representing Knowledge  One of earliest debates in psychology concerns the role of imagery in thought  early: thoughts were images --> thought can’t be without images  early 19 century : we can think without images --> the proposer could think but had trouble forming images  Imagery is a mental representation of something that isn’t currently present  mainly visual  doesn’t have to be visual --> also auditory (song stuck in head) or olfactory (smell) imagery  Different than symbolic representation which is an arbitrary mental representation of a concept  imagery is opposite of symbolic representation --> which in no way resemble the real world --> arbitrary symbol --> the word “dog” doesn’t look or sound like a dog  imagery representation look like things in real world --> analogue  According to Paivio’s dual-code theory, thoughts can be represented in 2 ways:  As analogue codes / depictive representations (images)  As symbolic codes (words)  Dual-code theory describes only one way of representing images (as depictive representations) two ways of representing thoughts ( think in terms of images and words) and one way of representing images  The functional-equivalence hypothesis believes all images are represented as analogue codes  images are functionally equivalent to the things in the real world  analogue code & depictive representation & functional-equivalence --> all imagery --> all say: images are similar to the real world  Another theory of how images are represented is propositional theory  we don’t think in terms of images  Images are epiphenomena of underlying propositional networks  knowledge is represented by thoughts  recognize that there are such things as images --> but they are by- product of our thoughts  e.g. laptop does processes such as calculation and also releases heat --> the more processing, the more heat --> but heat from laptop is a by-product of the processes going on --> it doesn’t cause the process in the computer  in the same way, as we think, we have images --> there is this processing going on and we get images --> but images are not related to our thoughts --> they are independent of our thoughts and don’t cause us to think --> formed as we think or because we think  which comes first? Which one doe we use to store knowledge?  dual-code: all knowledge are either words or images --> think in terms of words and images --> images are analogous to real life (resemble things in real world) --> images and words are our thoughts  functional equivalence theory: focus on images  propositional: knowledge is thought --> images are not thoughts, just tool we use to express ourselves  which comes first? which way do we use to store knowledge?  dual code --> store by images and words  propositional --> knowledge is stored by ideas  when describing it, we use images and words --> but knowledge is not stored as words or images  stored as proposition --> when bringing the proposition to mind, we may use images or words  debate: are we thinking in ideas/proposition (propositional theory) or skip it and go right to images and words (dual-code theory) Propositional Theory  A proposition is the smallest unit of knowledge that can stand as an assertion  something we can verify i.e., the smallest unit about which it makes sense to make a judgment of true/false might not necessarily true e.g. i am tall --> proposition; i am --> not proposition because can’t verify  These are not tied to any specific modality (形形形 thoughts are disembodied ideas --> proposition is just the ideas --> can’t say them or act out or draw --> can use vision to describe it but it is not idea proposition are just the ideas --> no modality --> just thoughts (no visual thoughts or auditory) --> idea doesn’t change --> idea is not concrete imagery has modality --> e.g. auditory and visual --> different from each other --> concrete representation the real world  Propositions preserve only the meaning of an item  Propositions consist of an agent and a relation  Agent: the “thing” your referring to (noun)  Relation: explains what’s happening to the agent (verb, adjective, etc)  Expressed as: relation (agent) --> (proposition notation)  E.g. The duck is wet --> wet(duck) --> wet duck is how we represent the proposition “the duck is wet” --> this is the idea --> we can express the idea in many different ways --> say it or draw it  E.g. The duck quacks -> quack(duck) Functional-equivalence hypothesis  do we store images as actual images or as ideas and create images from ideas?  we store images as actual images (how we perceive it)  different name for the analogue code of duel-code theory  need to meet 5 criteria to prove that we do think in images  since we found evidence against implicit coding and some evidence is mixed  when we are using imagery, it is functionally equivalence to perception  can’t answer which one we store  Finke (1989) described 5 ways that images can be similar to physical objects  should be functionally equivalent to real world in 5 ways --> meet the 5 criteria of motionormational equivalence: imagined and physical movements use the same laws  images have to obey the same physical laws as in real world  usually in terms of time --> imagine walking around the table once should take less time than walking around the table twice  obey laws of physics --> things don’t necessarily need to exist --> just at two places at the same time --> e.g. Cheetah flying --> need to go up and can’t be  evidence: mental rotation and image scanning 2. Spatial equivalence: arrangement of elements in images are the same as those in physical objects  images = photograph of real word  people at back should be smaller than people in front  spatial and size  same layout  evidence: image scaling --> relative size vs. reaction time when answering questions about it (rabbit and elephant) 3. Implicit encoding: information about physical objects can be attained from images even though not stored explicitly  get info from the images in the same way as if we were looking at the objects  info obtained from images should be the same as that in the real world  imagine the kitchen and count number of cupboard  not supported by complex and ambiguous pictures 4. Structural equivalence: construction of images and physical objects uses similar processes  how we make or build objects  the process of creating images is the same as process that creating or building real things  e.g. drawing a simple house is easier and take less time --> imagining a simple house is also easier and take less time --> than a detailed house  evidence: image complexity --> quicker to imagine 2 overlapping rectangles than 5 squares that both constitute the same shape 5. Perceptual equivalence: similar brain mechanisms are used for imagery and perception  e.g. occipital lobe should be activated when perceive and imagine  evidence: interference --> imagining tree or note and detect arrow or tone (behavioral) and some neuropsychological evidence such as eye movement & brain activity & spatial neglect and people with brain damage Let’s look at some evidence… Principle Support Transformational Spatial Implicit Structural Perceptual Mental Rotation --> Transformational equivalence --> images obey similar physical laws as in real word  interested in how much time is required to answer the questions  a) lower degree of rotation; b) higher degree of rotation  angle of degree increases = reaction time increases --> obey rule of physics  in real world: for same shape, rotate 20 degrees is fast but rotate 80 degrees takes longer --> larger rotation angles require more reaction time  in real world: for different shape, need to rotate in all degrees to compare --> take longer --> same reaction time because no matter how much you rotate it, the shapes are different  support transformational equivalence Image Scanning --> Transformational equivalence  Memorize this map   Imagine you’re at the beach and going to somewhere --> takes longer to imagine going to longer distances  evidence for transformational equivalence Let’s look at some evidence… Principle Support Transformational functional equivalence in some not for light coming on different location --> quite a lot of evidence for transformational equivalence Implicit Image Scaling --> spatial equivalence  what size --> relative --> in relation to each other --> hard to be done --> so experiment = compare two objects  Imagine a rabbit standing next to an elephant  Does an elephant have eye lashes? fast --> see quite clearly because it is big  Does a rabbit have eye lashes? slow --> need to zoom in because it is very small compared to elephant  should be able to see everything about the elephant clearly but not so much for rabbit  imagery: should be able to imagine everything about the elephant clearly but not details for rabbit (--> in real life, need to walk toward the rabbit to look at it) --> need to zoom in to rabbit --> slower in answering question about rabbit --> support for spatial equivalence  Imagine a rabbit standing next to a fly  Does a fly have whiskers? slow --> need to zoom in which takes longer  Does a rabbit have whiskers? fast  what if it is semantic knowledge that enables us to answer the question timeif this is the case, then the change in size wouldn’t matter or affect reaction  Imagine an elephant-sized rabbit standing next to a rabbit-sized elephant  Does an elephant have eye lashes? slow --> need to zoom in  see all the detailsve eye lashes? fast --> now rabbit is big one and we can  evidence for spatial equivalence --> functional equivalence Let’s look at some evidence… Principle Support Transformational Functional equivalence in some circumstances Spatial functional equivalence Implicit Structural Perceptual Implicit coding --> get knowledge from images the same way as getting knowledge from real objects Difficult and Ambiguous Figures   give the same, ambiguous image and half of the group one word and the other half another word --> then ask them to remember the images and draw them  if people were storing the image --> analogous thoughts --> more or less draw the images and do the same for both groups --> but what people drew matched not the images but the word  people didn’t store the image --> they stored the word or meaning of the image  not analogous or depictive representation  when just given the image --> people don’t store the exact snapshot but the meaning they came up themselves  against implicit encoding Difficult and Ambiguous Figures  Reed (1974) --> Isreal flag symbol (two triangles) --> is parallelogram part of the drawing?  when remembering an image, we store meaning and recreate the image --> not picture or snapshot  when asked whether a shape is part of the image --> only 14% got correct when they are thinking of it --> when given the image again, more able to see the shape  against implicit encoding --> not able to get same info from image as that from real object --> we are not storing image --> we are storing proposition (idea or meaning) --> not storing snapshot Let’s look at some evidence… Principle Support Transformational Functional equivalence in some circumstances Functional equivalence Spatial propositional in special circumstances (difficult Implicit and ambiguous figures --> don’t have the knowledge before) --> if it is a very familiar picture, people have it in semantic memory and don’t need to look at image to get the answer Structural Perceptual Image Complexity --> structural equivalence   some were told this is five squares into a shape of a cross and others told this is two overlapping rectangles  draw 5 squares takes more time than draw 2 rectangles  for those that were told this is five squares: takes longer bring image back in mind or memory  if it is longer to create or draw in real life, it is longer to create the images (to imagine the thing) --> how we create and imagine the object is equivalent  support for structural equivalence Let’s look at some evidence… Principle Support Functional equivalence in some circumstances Transformational functional equivalence Spatial Implicit propositional in special circumstances functional equivalence Structural Perceptual Perceptual equivalence Interference (behavioral experiment)  if the brain mechanism for perception and imagery is the same, then we should see interference between the two --> two visual task at the same time, they for perception and imagery, we should see the same interference if same mechanism  If imagery is analogous to real perception, than real and imaged stimuli should interact with each other  Segal & Fusella (1970)  first row: imaged stimulus  second row: real stimulus  third row: reaction time  e.g. imagining a tree / sound of a piano (imagery task) --> while look out for both an arrow and listen to the tone (vigilance task)  vigilance task --> waiting for the presence of stimulus --> when stimulus come up, they need to press the button  when already using visual imagery process by imagining a tree, less mechanism resource to detect arrow --> slower reaction time --> same visual  when imagining sound of piano --> auditory resource is used up by imagery, and less available resource to detect the tone --> slower reaction time  perception uses the same mechanism as imagery Imagine a tree Imagine the sound of a piano detect detect detect detect --> tone --> tone slow fast fast slow Neuropsychological evidence  the same object (Norton & Stark, 1972)oking at an object and later imagining  when perceiving a scene --> track eye movement --> take off the scene and ask them to imagine the scene --> track eye movement again --> when at the scene --> similar process going on when looking at a scene andooking imagining the scene  Similar brain areas are active during real perception and imagery (look at scene and also imagining scene)  in the brain (left fusiform gyrus)de evidence for a separate imaging area  more activated area for perception than imagery --> but area of activation is generally the same  Patients with visual spatial neglect have similar problems with imagery (e.g. Bisiach & Luzzatti, 1978)  half of the world --> left side is gone --> describe everything on the right half --> copy right half of a picture --> it is not disturbing to them (didn’t matter) --> they are just unconscious of it --> they don’t bothered by it --> can’t direct their doesn’t exist or attention to the other side --> to them, half of the side  when imaging: will only describe half of the scene or thing --> will describe exactly what they see --> one facing front, describe only the right side --> turn around, describe only the other half side  support for perceptual equivalence  Case studies of brain damaged individuals provides mixed evidence:  MGS had normal imagery prior to unilateral removal of occipital cortex, but reduced visual field and imagery after surgery  missing both perception and imagery --> describe what they would see which is missing somethings --> described images same way as seeing  support  CK had a serious deficit in form perception but could draw items from memory  could imagine but couldn’t perceive  LH had intact visual perception, mental rotation, image scanning, size scali
More Less

Related notes for PSY100H1

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit