CHAP 7 reviewer - Summary Cognitive Psychology PDF

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CHAP 7: MENTAL IMAGES AND PROPOSITIONKNOWLEDGE REPRESENTATION the form for what you know I your mind about things, ideas, events, and so on, in the outside world. MENTAL REPRESENTION *none of us has conscious access to our own knowledge representation processes, and self-reported information and sel...

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CHAP 7: MENTAL IMAGES AND PROPOSITION KNOWLEDGE REPRESENTATION -the form for what you know I your mind about things, ideas, events, and so on, in the outside world. MENTAL REPRESENTION *none of us has conscious access to our own knowledge representation processes, and self-reported information and self-reported info about these processes is highly unreliable. *RATIONALIST APPROACH- another to observe how we represent knowledge in our minds (we try to deduce logically how people present knowledge) 2 KINDS OF KNOWLEDGE STRUCTURES 1. DECLARATIVE KNOWLEDGE - facts that can be stated. (date of birth, names etc.) 2. PROCEDURAL KNOWLEDGE - knowledge of procedures that can be implemented (tying shoelace, driving a car etc.) 2 SOURCES OF EMPIRCAL DATA ON KNOWLEDGE REPRESENTAION 1.STANDARD LABORATORY EXPERIMENT -indirectly study knowledge representation because they cannot look into people’s minds directly. 2. NEUROPSYCHOLOGICAL STUDIES -observe how the normal brain responds to various cognitive task involving knowledge representations -observe the links between the various deficits in knowledge representation and associated pathologies in the brain. COMMUNICATING KNOWLEDGE: PICTURES vs. WORDS *some ideas are better and more easily represented in pictures, whereas others are better represented in words. (“what is the shape of the chicken egg?”-you might find drawing the egg easier than describing it) (“what is justice?” describing such an abstract concept in words would already be difficult, but doing so pictorially would be even harder) --we may represent things and ideas in pictures or words . but neither picture nor words capture all the characteristics of what they represents, and each more readily captures some kind of information than other kinds --some cognitive psychologists have suggested that we have: a. b. c.

Some mental representations that resemble pictorial, analogous images. Other mental representation that are higly symbolic, like words Perhaps even more fundamental propositional representation that are in a pure abstract “mentalese” that is neither verbal nor pictorial, which cognitive psychologists often represent in this highly simplified shorthand.

SYMBOLIC REPRESENTATION

-the relationship between the word and what it represents is simply arbitrary. -“cat” may capture some kinds of info but not other kinds of info (suppose our own mental representations for the meanings of words resemble those of the dictionary, then the word “cat” connotes an animal ho eats meat, nurse its young, etc.) *PICTURES aptly capture concrete and spatial information in a manner analogous to whatever it represents. (convey all features simultaneously) *in general, any rules for creating or understanding pictures pertain to the analogous relationship between the picture and what it represents *WORDS, handily capture abstract and categorical info in a manner that is symbolic of whatever the words represent. (representations in words usually convey info sequentially) PICTURES IN YOUR MIND: MENTAL IMAGERY IMAGERY -mental representation of things that are not currently seen or sensed by the sense organs. (you don’t actually smell the grass and see the buildings but you still can imagine them) -mental imagery can represent things that you have never experienced. -may involve mental representation in any of the sensory modalities (hearing, smell, or taste; imagine the sound of fire alarm, favorite song, smell of bacon etc.) -most of us are aware of visual imagery than of other forms of imagery. APPLICATIONS OF MENTAL IMAGERY TO OTHER FIELDS OF PSYCHOLOGY *guided imagery techniques to control pain and to strengthen immune system responses and otherwise promote health. -imagine being in the beach feeling, letting your pain fade into the background -imagine cells destroying bacteria inside your body *such techniques are also helpful in overcoming psychological problems - such as phobias and other anxiety disorders *engineers, biochemist, and other scientists and technologists use imagery to think about various structures and to solve problems in their chosen fields --some of us are better able to create mental images than others --use of mental images can help to improve memory --Down syndrome, the use of mental images in conjunction with hearing a story improved memory for the material as compared w/ just hearing the story. ---all images of everything we ever sense may be stored as exact copies of physical images, but realistically to store every observed physical image in the brain seems impossible *TARTAGLI (2009) -presented participants with vertical parallel arrangement of three lines

--practice using mental images resulted in participants becoming more sensitive to the asymmetry toward either the left or right side. *architects, although they were not permitted to draw sketches in the early design phase of a project did not affect the design outcome and cognitive activity---they were not allowed to draw sketches, they just used mental imaging

-THIS FINDING SUGGEST THE USE OF TWO DISTINCT CODES FOR MENTAL REPRESENTATION OF KNOWLEDGE: 1. IMAGINAL (analogical) CODES 2. VERBAL (symbolic) CODES

STORING KOWLEDGE AS ABSTRACT CONCEPTS: PROPOSITIONAL THEORY

DUAL-CODE THEORY: IMAGES AND SYMBOLS (PAVIO) DUAL-CODE THEORY -we use both pictorial and verbal codes for representing information in our minds -these two code organize information into knowledge that can be acted on , stored somehow, and later retrieved for subsequent use. ANOLOG CODES -resemble the objects they are representing -(movements of the hands on an analog clock are analogous to the passage of time) ---the mental images we form in our minds are analogous to the physical stimuli we observe SYMBOLIC CODE -a form of knowledge representation that has been chosen arbitrarily to stand for something that does not perceptually resemble what is being represented -“sand” can be used to represent the flow of time -a symbol may be anything that is arbitrarily designated to stand for something other than itself. *PAVIO noted that verbal info seems to be processed differently than pictorial information. *in one study, (participants were asked to recall words). -Participants more easily recalled the pictures when they were allowed to do so in any order -but they more readily recalled the sequence in w/c the words were presented than the sequence for the pictures

*BROOKS actual visual perception could interfere with visual imagery; -the need to produce a verbal response could interfere w/ the simultaneous mental manipulation of words (both task and response required the same system for completion; interference were measured by slowdowns in response times) -participants did show slower response times in performing the pictorial task when asked to respond using a competing visual display, as compared w/ when they were using a noninterfering response medium -similar, more interference in performing verbal task *thus, a response involving visual perception can interfere w/ a task involving manipulations of a visual image. -similarly, a response involving verbal expression can interfere w/ a task involving mental manipulations of a verbal statement.

PROPOSITIONAL THEORY -suggests that we do not store mental representations in the form of images or mere words. -we may experience our mental representations as images, but these images are “ epiphenomena” –secondary and derivative phenomena that occur as a result of other more basic cognitive processes. -our mental representations “mentalese” more closely resemble the abstract form of a proposition. PROPOSITION -is the meaning underlying a particular relationship among concepts. --according to propositional view, both images (the cat and the table) and verbal statements are mentally presented in terms of their deep meanings, and not as a specific images or words) -then, when we finish to retrieve the info from storage, the propositional representation is retrieved. -from it our minds recreate the verbal or imaginal code relatively accurately LIMITATIONS OF MENTAL IMAGES *people have analogical mental images that are imprecise in some ways *ambiguous figure- can be interpreted in more than one way (researches use such figures (perception)to determine whether mental representations of images are truly analogical to perceptions of physical objects) *CHAMBERS AND REISBERG’S -You need to have an actual percept (object of perception) of the figure in front of you so you can guess at an alternative interpretation of the figure -this research INDICATE that mental representations of figures are not the same as percepts of these figures ( -people plainly do not use images to represent what they see -propositional code may override the imaginal code in some circumstances -semantic (verbal) info (labels for figures) tends to distort recall of visual images in the direction of the meaning of the images. *FINKE, PINKER, FARAH -in some situations, mental images can be combined effectively. *it appears that propositional code are less likely to influence imaginal ones when participants create their own mental images, rather than when the participants are presented w/ a picture to be represented The believe that the mental reinterpretation of ambiguous figures involves two manipulations

1.MENTAL REALIGNMENT OF THE REFERENCE FRAME -this realignment would involve a shift in the positional orientations of the figures on the mental “page” or “screen” on w/c the image is displayed. (the shift would be the duck’s back to the rabbit’s front, and the duck’s front to the rabbit’s back 2.MENTAL RECONSTRUAL (reinterpretation) OF PARTS OF THE FIGURE -it would be the duck’s bill as the rabbit’s ear 1.IMPLICIT REFERENCE FRAME HINT –participants first were shown another ambiguous figure involving realignment of the reference frame 2. EXPLICIT REFERENCE FRAME HINT- participants were asked to modify the reference frame by considering either “the back of the head of the animal they had already seen as the front of the head of some animal”. “or front of the thing you were seeing as the back of something else”(abstract hint) 3.ATTENTIONAL HINT- participants were directed to attend to regions of the figure were alignments or reconstruals were to occur. 4.CONSTRUAL FROM “GOOD” PARTS- participants was asked to construe an image from parts determined to be “good” (according to both objective (geometrical) & empirical (interrater agreement criteria), rather than from parts determined to be “bad” 9according to similar criteria) ---the processes involved in constructing and manipulating mental images are similar to the process involved in perceptual processes FUNCTIONAL EQUIVALENCE- the individuals using about the same operations to serve about the same purposes for their respective domains.

vividly. Then the participants were either presented w/ the objects or were asked to visualized them. ---the researchers found that while both imagery and perception used similar brain areas, the contributions of the areas and their level of activation differed depending on whether the participants actually saw or just mentally imagined an object ---this finding makes sense given that there’s no visual input from the eyes during imagery, w/c leads to a decrease in info compared w/ visual perception. *schizophrenia- this “hearing” is the result of internally generated material. -these patients have difficulty discriminating between many different types of self-produced and externally provided stimuli -in sum, it is believed that auditory hallucinations occur at least in part of malfunctions of the auditory imaging system and problematic perception processes (these challenges make it difficult for afflicted individuals to differentiate between internal images and the perception of external stimuli.) MENTAL ROTATIONS -involves rotationally transforming an object’s visual mental image --just like you can physically rotate a water bottle you hold in your hands, you can also imagine a water bottle in your mind and rotate it in the mind. * response time is longer for degraded stimulistimuli that are blurry, incomplete or otherwise, less informative, than for intact stimuli. *practice effects- improvements in performance associated w/ increased practice. (may lead to increase familiarity) ---when participants have practice in mentally rotating particular figures (increasing their familiarity), their performance improves.

WOMEN

MEN

*less parietal activation, in completing rotational task

*parietal activation, in completing rotational task

*additional inferior frontal activation

*the right side of the brain dominates in the spatial task

MENTAL MANIPULATIONS OF IMAGES FUNCTIONAL EQUIVALENCE HYPOTHESIS -although visual imagery is not identical to visual perception, it is functionally equivalent to it. -the functionally equivalent images are thus analogous to the physical percept s they represent --this view essentially suggests that we use images rather the proposition in knowledge representation for concrete objects that can be pictured in mind. NEUROSCIENCE AND FUNCTIONAL EQUIVALENCE -when participants either viewed or imagined an image activation of similar brain areas was noted, particular, in the frontal and parietal regions -imagery can evoke responses in the high-level visual brain areas and the visual primary cortex—areas that highly involved in processing of visual stimuli we see in our see

*in spatial task, involve both sides of the brain *proportionally have greater amounts of gray matter in the parietal lobe than men (performance disadvantage for mental rotation

ference exist either in performance or in neurological activation *training causes the gender differences to decrease or even to disappear *test anxiety maybe increases more in women than in men, when stricter limits apply or simply that cognitive processing for problem solving is faster for males.

*IN A STUDY, participants were first familiarized w/ the images of several objects and how to visualize them IMAGE SCALING

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(internet)

IMAGE SCANNING -the key idea underlying image scanning research is that images can be scanned in much the same way as physical percepts can be scanned. -our strategies and responses for imaginal scanning should be the same as for perceptual scanning *Stephen Kosslyn- has found additional support for his hypothesis that we use mental images in image scanning. *this finding indicates there participants that the same mechanisms were used, no matter whether participants looked at the actual dots presented w/ the arrow, or looked only at the arrow, needing to imagine the dots.

-the criterion of the possibility of verbal expression distinguishes Johnson-Laird’s view from that of other cognitive psychologists MENTAL MODELS -knowledge structures that individuals construct to understand and explain their experiences -the models are constrained by the individuals’ implicit theories about these experiences, w/c can be more or less accurate. *Ex. You may have a mental model to account for how planes fly into the air ---but the model depends--not on physical or other laws but rather--beliefs about them. *the same would apply to the creation of mental models from text or symbolic reasoning problems as from accounts of planes flying in the air.

If participants did not use a spatial representation but rather a code based on Pylyshyn’s propositional theory (1973), then the distance between the points and the arrow should not have influenced reaction time, but it did. (recall that the experiment by Shepard and Metzler “1971” found linearly increasing reaction times for mental rotations as the angle of rotation increased.

”the cat is under the table” *as proposition-“it is verbally expressible” *as an image- “of a particular cat in a particular situation under a particular table” *as a mental model- “of any cat and table”

REPRESENTATIONAL NEGLECT -a person asked to imagine a scene and then describe it ignores half of the imagined scene. *spatial neglect- a person ignores half of his or her visual field.

PROOF FOR THE USE OF “MENTAL MODELS” -experiment by Mani and Johnson-Laird (1982) *Determinate descriptions-participants received precise location info for each object in spatial array. --relied on mental images, no on verbatim descriptions

---similarly, when subjects w/ representational neglect were presented w/ an image, they descrbed the entire image. However when the image was removed and they were asked to describe the image from memory, they failed to describe the left portion. ------in the previous discussion, we addressed the first three of Finke’s criteria for imaginal representations ------mental imagery appears functionally equivalent to perception in many ways. This conclusion is based on studies of mental rotations, image scaling (sizing), and image scanning. ------the studies involving ambiguous figures and unfamiliar mental manipulations, however, suggest that there are limits to the analogy between perception and imagery. DO EXPERIMENTERS’ EXPECTATIONSA INFLUENCE EXPERIMENT OUTCOMES? -she found that the experimenter expectancies did influence participants’ responses in three tasks: image scanning, mental rotations, and another task comparing perceptual performance w/ imaginal performance. ----when experimenters expected imaginal performance to be better than perceptual performance, participants responded accordingly, and vice versa. ----thus, experimental participants performing visualization tasks may be responding in part of the experimenters’ expectations regarding the outcomes. JOHNSON-LAIRD’S MENTAL MODELS -an alternative synthesis of the literature suggests that mental representations may take any of three forms: Proposition, Images, or Mental Models *here, propositions are fully abstracted representations of meaning that are verbally expressible.

*Indeterminate description-participants received ambiguous location info for objects in the array. --remembered the verbatim descriptions (because of the multitude of possibilities for mental models) -Kosslyn (Kerr) *blind participants responded more slowly to all tasks than did the sighted participants *but Kerr’s participants still showed similar response patterns to those of sighted participants --they showed faster response times when scanning shorter distances than when scanning longer distances; and also faster when answering questions about images of larger objects than about images of smaller objects ---at least in some respects, spatial imagery appears not to involve representations that are actual analogs to visual percepts. *haptic(touch-based) imagery suggests alternative modalities for mental imagery. *auditory modality partcipants seem to have “auditory” mental images, just as they have “visual” mental images *haptic imagery- it is easier to conceptualize auditory imagery in terms of “mental models” than strictly in terms of the kinds of “pictorial mental representations” of w/c people speak when they think of visual imagery. --when one generates an auditory image, the same brain areas as those involved in hearinf are engaged. Faulty mental models- are responsible for many errors in thinking Experience- is a useful tool for the repair of faulty mental models

----in sum, MENTAL MODELS provide an additional means of representation in addition to propositions and visual images. LEFT BRAIN or RIGHT BRAIN: WHERE IS INFO MANIPULATED? -initial neuropsychological research on imagery came from studies of patients w/ identified lesions and from split-brain patients. *Right hemisphere- appears to represent and manipulate visuospatial knowledge in manner similar to perception. - represents knowledge in a manner that is analogous to our physical environment *Left hemisphere- appears to be more proficient in representing and manipulating verbal and other symbol based knowledge. - has the ability to manipulate imaginal components and symbols and to generate entirely new info. *Corballis- humans alone can conceive what they have never pe...