SP605 Cognitive Psychology PDF

Preview

Summary

SP605 Cognitive Psychology Diva Wong SP605 Cognitive Psychology Table of Contents SP605 Cognitive Psychology .............................................................................................. 1 Week 13 Introduction to cognitive psychology ....................................................

Description

SP605 Cognitive Psychology

Diva Wong

SP605 Cognitive Psychology

Tabl Table eo off Co Conte nte ntents nts

SP605 Cognitive Psychology .............................................................................................. 1 Week 13 Introduction to cognitive psychology .......................................................................... 2 Week 14 Language ................................................................................................................... 6 Week 15 Long Term Memory.................................................................................................. 16 Week 16 Episodic Memory ..................................................................................................... 27 Week 17 Vision 1 Low Level Vision ......................................................................................... 33 Week 19 Vision 2 Object Recognition ..................................................................................... 38 Week 20 Attention................................................................................................................. 44 Week 21 Executive control and social cognition ...................................................................... 51 Week 22 Emotion and Cognition............................................................................................. 57 Week 23 Visual Imagery ......................................................................................................... 65

1

SP605 Cognitive Psychology

Diva Wong

Week 13 Introduction to cognitive psychology • What is cognitive psychology o Everything that is done such as visual perception, auditory perception etc are cognitive psychology o Is the production different, shared? o How do they work? o Definition* ▪ Visual input, what kind of elaboration are done in the mind to store or interpret information ▪ Even working in the absence of relevant stimulation ▪ Absence of external stimulation and retrieve information from memory • History o 1950s-1980s ▪ Behaviourist were only worried about studying behaviour ▪ No way to study brain as we cannot see cognition ▪ Only interested in studying* ▪ Things started to change in the 50s are it is not enough to just study about behaviour rather the cognition and processes behind the behaviour ▪ Increase interest in language (psycholinguistics) and the mind ▪ Once environment was fertile for a new approach this propelled the development of computers ▪ Revolutionised psychology as psychologist started to think that we should use the computer analogy to describe how humans produce an output ▪ Keyboard, mouse (computer) -> senses (human) ▪ Operate in a similar way to the computer • Information processing paradigm o Still explained in the development of mind computer metaphor • Basic assumptions of cognitivism o Most cognitive models start from the input (senses) to the mediation process to the output (behaviour) o Behaviour: not a complex behaviour, particular process from particular input o Cognitive psychology is interested in the mediational process • Information processing approach o Serial ▪ only one process at the time ▪ one direction from one to another ▪ * o We know now that we can process two things at the same time o Bottom-up ▪ * • Why learn about cognitive psychology o Tells us everything about why and how we do anything o What are the processes mechanisms in what we can do o Be able to restore a behaviour when we know about the deficit • Setting for cognitive research o Naturalistic ▪ Observation o Interested in functioning of experimental process o Controlled experiment to manipulate variables of interest to* • Cognitive psychology ecologically valid o Technology now is still better to conduct well controlled studies o Get a lot more information than in a realistic setting o Cognitive psychology decomposes information in a lot of processes and study behaviour in a lot of controlled experiment

2

SP605 Cognitive Psychology •

•

•

•

•

•

Diva Wong

Applications of cognitive psychology o Can be used in schools for teachers to know about learning styles and how memory develops in children o Marketing companies use knowledge of cognitive psychology to design more effective marketing advertisement o Commercial examples Clinical application of cognitive psychology o Patients with brain damage have cognitive repairment o Cognitive neglect ▪ Patients have damage to one side of brain and neglect the contralateral objects of space ▪ Establish as an attentional rather sensory deficit Other applications of cognitive psychology o Follow automatically at the gaze of others o Engineering ▪ Buttons and where all these should be placed to minimised instruction and the maximise attention o Judicial ▪ Recognise faces better for passport ▪ Can work in emotional situation ▪ Can they recognise defender in a line up o Of interest in other areas as well as real world Approaches of cognitive psychology o Experimental cognitive psychology ▪ Well controlled experiments ▪ Information from patients with brain damage o Cognitive neuroscience o Cognitive neuropsychology o Computational cognitive science Cross disciplinary approaches o Social neuroscience ▪ Bridge the gap between cognitive neuroscience and social psychology ▪ How social neuroscience can affect the brain ▪ Example • Perception of trustworthiness Methods in experimental cognitive psychology o Have to operationalise precisely what the process we are interested in o Reaction Time ▪ Time between the presentation of a stimulus and the production of a motor response ▪ Donders (1868) • Subtraction method o Discriminate different colour stimuli ▪ 3 components • Stimulus discrimination • Response selection • Response execution o Go/No-Go task ▪ Stimulus 1 press A ▪ Stimulus 2 press nothing ▪ Stimulus discrimination and response execution o Simple RT task ▪ When either stimulus appears press a button

3

SP605 Cognitive Psychology

Diva Wong ▪

Response execution but not stimulus discrimination and response selection

Results ▪ Response selection is the time to perform stimulus and execute a response ▪ Response execution is the time taken for the simple RT task ▪ Stimulus discrimination is subtracting RS and RE from the time for the choice reaction time task ▪ To do more experiment and subtracting times • Problems with the subtraction methods o Diner fround average time for the choice RT taks were shorter than the average time for the Go/No Go task o Might interact in different range, can’t separate time that easily o Additive factor logic ▪ Instead of doing more task that tap into different components, do one task ▪ That tasks keeps everything constant except the viable of interest ▪ Only difference in reaction time that in* o Example 1 ▪ Visually encode and scan display, decide which button to press and the action of pressing the button ▪ Task is always the same and the difference is how many letters is displayed ▪ Only difference in RT between the 6 and 4 letter display is the scan time o Example 2 ▪ Short term memory scan ▪ Whether letter is present or not in the string of letter ▪ String of letter increase in length ▪ How long it takes to scan letters ▪ Also tell you about what process is used in response ▪ Exhaustive search • scan whole string • reaction time the same ▪ Self-terminating search • if letter is present then you stop the search • when letter is not present would have same reaction time as exhaustive search ▪ Parallel search • Compare letter to all letters in the string, doesn’t matter how long the string is ▪ Factors that affect RT* o Accuracy ▪ How well people can perform the task o Reaction time and accuracy can interact ▪ Doing task fast might sacrifice accuracy ▪ Doing task more accuracy might sacrifice reaction time ▪ Only make sense when* o Conclusions* Methods in cognitive neuroscience o Which network in the brain is involved in the process o

•

4

SP605 Cognitive Psychology o o

o

Diva Wong

There are advantages of using cognitive neuroscience methods Two methods can be * ▪ Example: Biological and behavioural measures • Objects ▪ Example of conflicting data • Behaviour and Neuroscientific results do not correlate • Should we believe everything what neuroscience tells us or behavioural science ▪ Two possible views • Brain imaging data must be corroborated by behavioural data because o * • Brain data does not need convergent behavioural data to be interpreted* How to treat conflicting imaging and RT data ▪ Replication

5

SP605 Cognitive Psychology

Diva Wong

Week 14 Language • Introduction to language o A System for communication but not the same as communication o Sounds we can’t hear but can be a communication between animals and species o Monkeys can communicate with different sounds for different predators o Complex way of communication o What is different about human language? ▪ We have rules on how to use words and letters ▪ Language is a system of communication that uses symbols ▪ We use symbols • Language is symbolic o Decided at some point to use words as symbols o All communication is based on symbols o When you are communicating feelings, you use emojis but the symbol doesn’t necessarily mean happiness o With the exception of some class of words, most of the words we use Is symbolic, does not resemble actual reference • What is language o Function ▪ Express state of communicator ▪ Issue signals that can elicit responses from listener ▪ Describe concepts, ideas, or external states ▪ Comment on a previous communication ▪ Can reflect on feelings and ability ▪ Communicating present things that are not in the environment ▪ Most impressive achievement of the brain, evolution • Facts o Adults know 70,000 words (they produce some 40,000) o Not just know the sound of the word but also others ▪ Phonology • The sound of it ▪ Sematic • Meaning, what it is referred to in the real world ▪ Spelling ▪ Morphology • Smallest unit of meaning e.g. “slow-ly”, “cat-s” ▪ Syntax • Grammar of the language, role of word in a sentence ▪ Articulation • What motor command needs to send to produce the word o All this knowledge is used very efficiently ▪ speakers produce ~ 2-3 words/sec • The study of language o How do humans learn language? o How do humans use language in adulthood? o What are other aspects of cognition that are used in language?

6

SP605 Cognitive Psychology • •

•

Diva Wong

Academic study of language o Psychology: Psycholinguistic, Language Acquisition, Language loss What do we need for language? o Symbolic building blocks ▪ Written language – an alphabet • 26 letters ▪ Spoken language – phonemes e.g. “c” = /k/ or /s/ • 44 phonemes • Because some letters in the alphabet can be pronounced in different ways ▪ Sign language – finger spelling • Make hand shapes that correspond to letters in the alphabet o Morphemes ▪ Linguistic unit of meaning that can be divided into smaller meaningful parts ▪ E.g. a word (‘dog’) or a word element (the ‘-s’ at the end of ‘dogs’). o Mental lexicon ▪ Keep words somewhere in our mind ▪ representation of the list of words known to find the ones we need ▪ dictionary, index of all the words we know o Semantic memory ▪ Meaning of the word will be put into the semantic memory o Grammar (syntax) ▪ Rules of language ▪ Placing words in different order can let sentence hold different meaning ▪ Subject -> verb -> object o Working memory ▪ Things can go wrong in different levels ▪ Can be damaged by brain lesion o Theory of mind ▪ Ability to understand the perspective of someone else o Pragmatic knowledge ▪ Infer meaning beyond the literal meaning than the word Language comprehension o Spoken and written language comprehension ▪ Modality specific • Different depending on whether the modality is auditory or visual • Acoustic/visual analysis of input • Make sense that the input is a word ▪ Lexical stage • Input by either auditory word form or visual word form • Includes both information of sound and spelling of word • Inventory that is held in the mind for words, everything about the word • Once activate the entry of the particular word of the lexical then can access the meaning ▪ Conceptual stage • Access the concept of the word, what the word means • In the semantic memory ▪ Each box is a module and does something specific in the brain ▪ Any serial (arrow) is going in one direction ▪ Bottom up model however can it be a top down model too?

7

SP605 Cognitive Psychology

Diva Wong

Is it true that comprehension of knowledge is a bottom up model or a top down effect? Know what the word refers to or the context, also influences how fast we can extract the word from our databases Modular or interactive o Modular models of language (Fodor, 1983) ▪ Independent modules ▪ serial ▪ Strictly bottom up o Interactive models (McClelland & Rumelhart, 1981) ▪ Modules interact ▪ Parallel ▪ Both bottom up and top down Language perception o What factor affect word recognition ▪ Fast response = easy access, 400 ms ▪ Slow response = hard access, 500 ms ▪ This includes the time it takes to make the decision to press the button, plan the finger movement, and execute the button press ▪ Without to factor the affect, How quickly I can recognise a word in my lexicon ▪ Reaction time it takes also includes the time it takes to make the decision to press the button ▪ Many different variables that are correlated to determine the fast and slow response, affects speed of recognition • Length of word • Frequency, encounter more often • Age of acquisition • Familiarity • All interact in influencing the reaction time ▪ Need same, constant words to control the variables other than the one that you want to test e.g. control length, age of acquisition and familiarity and vary length ▪ Need to keep in mind the different factors that can affect how easily one word can be recognised Speech o Understanding speech ▪ Speech is actually a noise ▪ Have to extract sound from other auditory input ▪ Brain need to distinguish whether the sound is speech or noise, isolated ▪ Need to extract the individual words and meaning ▪ Keep in mind the difference of words and meaning of the current sentence ▪ Speech signal needs to be decoded itself. ▪ Words need to be recognized. ▪ Individual words need to be processed together (in sentences) to extract coherent meaning. ▪ Meaning of the current sentence needs to be integrated into discourse (conversation). o Language = noise ▪ Not much difference in the signal itself between speech and sound ▪ There are no gaps between words that tell us each word that is spoken ▪ Difficult to extract single word from this noise ▪ Still babies manage to understand speech • Can extract speech from noise o o

•

•

•

8

SP605 Cognitive Psychology

o

o

o

Diva Wong

• Can recognise patterns in noise • associate those patterns with meaning • learn the grammar of their language • produce equivalent patterns themselves ▪ Very early stage in development, babies can recognise what is speech and what is not ▪ Something in our brain that is hardwired to understand speech Decoding speech ▪ Segmentation • Ice cream vs. I scream • Because there are no pauses in the speech • Can’t distinguish any gap and cue to how to segment question • One difficulty in separating speech is knowing how to separate the different words in the sound (problem in speech recognition) ▪ Coarticulation • The way we articulate phoneme can be altered depending on the letter or the phoneme that comes after or that proceeds it o [k] in key vs cool o [s] in suit vs seat • Shape of the mouth to produce and position of the tongue it can be different depending on what letter comes next • Phonemes can sound different depending on what letters comes next • Advantages o Can predict what letter is coming next o Might make recognition faster o Has predictive value of which phoneme is coming next. • Disadvantage o Results in phonemes sounding slightly different for different words, which might make them harder to recognise. ▪ Speaker variation (problems faced by listener) • Different accent • Also makes speech recognition difficult for the person trying to understand Audio visual integration ▪ McGurk and Macdonald (1976) • A videotape of someone saying “ga” • Can hear a voice saying “ba” • Participants report hearing when having both input “da” • Integrate information from visual input • Hear ba but we know that’s not the mouth shape to say ba, brain is trying to make sense of this and the closest thing to ba that looks like ga is da • How the different phenomes are articulated influence the auditory perception of those phonemes • Are showing that there are top down effects even at this basic level of acoustic perception Context effects on speech perception ▪ How sentence context can affect a particular sound ▪ Phonemic restoration effect (Warren & Warren, 1970) • The sentence context can affect what we hear and the lower level of audio perception • Presented participant with sentences auditorily • Sentence heard:

9

SP605 Cognitive Psychology

o

o

o

o It was found that the *eel was on the axle. o It was found that the *eel was on the shoe. o It was found that the *eel was on the table. o It was found that the *eel was on the orange. o * = white noise masking the sound • Participants asked to report what they heard • Sentence reported: o It was found that the wheel was on the axle. o It was found that the heel was on the shoe. o It was found that the meal was on the table. o It was found that the peel was on the orange. • Participants restored the whole word even if the start of the word was missing and it was done dependent on the meaning of the sentence • Top down effect of meaning on auditory perception How do we solve these problems? ▪ Can we use top down influences to help us understand speech? • Yes, information such as sentence content and visual information can bias speech perception. • Can help us overcome difficulties in problems at the beginning ▪ Suggests interplay of bottom-up and top-down processing ensures accurate and rapid speech processing How are spoken words recognised? ▪ In speech, input develops over time ▪ Listeners can sometimes recognize words before a speaker has finished saying the word. ▪ Uniqueness point • That sound can only be that word, can be no other word • A point in the sound of the word that defines that word to be a particular word • The uniqueness point occurs early or late for different words: o For “candle”, occurs at final /l/. o For "slander,", occurs at the /d/. o For "spaghetti“, occurs at /spəɡ/. o Activation ▪ Entries in the lexical ▪ Activation like light bulbs switching on and off ▪ Activate all the words that are compatible with that sound Cohort model (Marslen-Wilson & Tyler, 1980) ▪ Influential model of auditory word recognition ▪ Will recognise the only word activated in the lexical (inventory of all the words known) ▪ Will deactivate when words are not compatible anymore ▪ Example Activation curves

• •

Diva Wong

Words that don’t include the letters heard will be deactivated

Written language

10

SP605 Cognitive Psychology o

o

Diva Wong

Reading ▪ Not hardwired in our brain as well as spoken language, don’t have specific areas for reading so would borrow from other processes ▪ Each word can be seen as a whole ▪ Spaces between words make segmentation easy ▪ Printed text is a clear signal but handwriting can be ambiguous ▪ Printed and written text can be re-read ▪ Punctuation can provide cues to sentence structure Speech perception

Different at a perceptual level but once you access the lexical and extract the m...