Working Memory & Cognitive Control Lecture Notes PDF

WORKING MEMORY & COGNITIVE CONTROL CHAPTER 9 WHAT ARE WE DISCUSSING IN THIS LECTURE VIDEO? Transient memories Sensory memory Short term memory Working memory Baddeley’s model Brain areas Clinical perspectives  SYSTEMS OF MEMORY Modal Model of Memory...

WORKING MEMORY & COGNITIVE CONTROL CHAPTER 9 WHAT ARE WE DISCUSSING IN THIS LECTURE VIDEO? Transient memories Sensory memory Short term memory Working memory Baddeley’s model Brain areas Clinical perspectives  SYSTEMS OF MEMORY Modal Model of Memory Atkinson & Shiffrin (1968) Environmental Sensory Working Long-Term Input Memory Memory Memory What is sensory memory? SENSORY MEMORY Sensory Memory: memory store before short term memory or working memory Sometimes called “iconic memory” or “transient memory” What the system registers in just one glance How much stuff does our sensory memory register? Sperling (1960) SENSORY MEMORY Let’s do a demonstration! Try to remember all the letters on the next slide. These letters will only appear for a limited time so pay close attention! SENSORY MEMORY A G F Y I R Q V H SENSORY MEMORY Now write down every letter you remember seeing.  SENSORY MEMORY A G F Y I R Q V H This is called a whole report procedure Try to write down (i.e., report) all of the letters you saw Typically remember a few letters SENSORY MEMORY Now we’re going to try again. This time, you will see an arrow next to a row of letters. Your job is to try and remember the letters in the row next to the arrow. Pay close attention! SENSORY MEMORY Q W B S T R I Y M SENSORY MEMORY Write down what you remember seeing, but ONLY for the row with the arrow next to it. SENSORY MEMORY Q W B S T R I Y M This is called a partial report procedure Write down (i.e., report) only part of the letters Typically able to remember more letters! SENSORY MEMORY Sensory memory: what the system registers in just one glance Large capacity Can hold many items Very brief duration Fades rapidly (can’t recall all the letters) Information not yet processed for meaning – only basic level processing TYPES OF SENSORY MEMORY Iconic memory: holds mental representations of visual stimuli Example: Sperling’s full vs. partial report study Echoic memory: holds mental representations of auditory stimuli Haptic memory: holds mental representations of touch stimuli BUT WHAT ABOUT PHOTOGRAPHIC MEMORY? Photographic memory vs. eidetic imagery Photographic memory: used in lay terms to describe flawless memories, like a photograph that is perfectly and permanently stored Eidetic imagery: the maintenance of visual imagery over several minutes Photographic memory is a myth In most instances, people with superior memory use successful strategies MEMORY COMPETITIONS People use memory strategies to win competitions! https://youtu.be/p0zmLo_edeo Examples from the video: Memorizing faces Extensive lists of numbers A deck of cards  SYSTEMS OF MEMORY Modal Model of Memory Atkinson & Shiffrin (1968) Environmental Sensory Working Long-Term Input Memory Memory Memory What is short term memory? SHORT TERM MEMORY Short term memory: Memory system that hold information for around 30 seconds SHORT TERM MEMORY Let’s try it out! On the next slide, you will see several 3 letter “trigrams”, such as ABY Your goal is to try to remember the trigrams. ZLV HRQ XTM YJB PVC NRO LDQ UTM Now, count backwards by 3s from 954. Now, write down the tri-grams that you can remember. HOW MANY DID YOU GET RIGHT? ZLV HRQ XTM YJB PVC NRO LDQ UTM SHORT TERM MEMORY Short term memory: Memory system that hold information for around 30 seconds Limited capacity – cannot hold much information at one time Limited duration – does not last very long Around 30 seconds SHORT TERM MEMORY But, what exactly is the purpose of short term memory? To hold and use information! How can we keep information active in short term memory? Rehearsal: rote repetition You probably did this when learning those trigrams This means there’s more to short-term memory  WORKING MEMORY Now, short term memory has been modified to working memory Working memory includes: storage and maintenance of information BADDELEY’S WORKING- MEMORY MODEL Central Executive Phonological Visuospatial loop sketchpad THE PHONOLOGICAL LOOP Holds and maintains auditory and subvocal (i.e., silent inner voice) information THE PHONOLOGICAL LOOP Let’s try this out! On the next slide, you will see a list of words. You will be allowed to study the words for 20 seconds. Pay close attention and try to remember them! THE PHONOLOGICAL LOOP Bat Hit Top Cat Door Love House Chain Cloud Stove Flower PHONOLOGICAL LOOP Now, write down all the words you can remember! PHONOLOGICAL LOOP Bat Hit Top Cat Door How did you Love do? House Chain Cloud Stove Flower THE PHONOLOGICAL LOOP Let’s try it again. On the next slide, you will see a list of words. You will be allowed to study the words for 20 seconds. After you study, you’ll have to do a completely unrelated task. Pay close attention and try to remember them! PHONOLOGICAL LOOP Truck Leash Moon Nail Book Chair King Tower Shoe Basket Light PHONOLOGICAL LOOP Count backwards by 3s from 900. PHONOLOGICAL LOOP Truck Leash Moon Nail How did you Book do this time? Chair King Tower Shoe Basket Light PHONOLOGICAL LOOP Rehearsal is very important for storing information in the phonological loop! Without rehearsal, people retain about 2 seconds’ worth of information If rehearsal is disrupted, phonological storage can’t occur This is why it was more challenging to remember the words the second time THE VISUOSPATIAL SKETCHPAD Responsible for: Storage of visual and spatial information Manipulation of visual and spatial information Also has a limited capacity  TESTS OF VISUAL MEMORY Delayed nonmatch-to-sample (DNMS) task Trial 1- chimp learns that a peanut is under a blue ball  TESTS OF VISUAL MEMORY Delayed nonmatch-to-sample (DNMS) task Trial 2 – chimp has to pick a different object to find the peanut Requires chimp to hold visual and spatial information in mind to remember a) the object and b) the location COGNITIVE CONTROL COGNITIVE CONTROL Cognitive control: the manipulation and application of working memory Planning Task switching Attention Inhibition Performed by the central executive in Baddeley’s model BADDELEY’S WORKING- MEMORY MODEL Central Executive Phonological Visuospatial loop sketchpad COGNITIVE CONTROL Central executive: The most important, most complex, and least well understood component Manipulates information in short-term memory Is the working component of working memory Cognitive control is related to many behaviors BEHAVIORS AND TASKS CONTROLLED UPDATING OF SHORT-TERM MEMORY Central executive updates working memory Receiving and evaluating sensory info Moving items into long-term memory Retrieving items from long-term memory Deciding what is needed for each task This is complicated! How do researchers examine all of these complex processes?? N-BACK TASKS Participant has to remember N amount of letters back when a certain target is read aloud Example: 2-back test Each time the number 7 is read aloud, have to say the number two numbers prior to the number 7 N-BACK TASKS Let’s try it out! I’m going to read a list of numbers. When I say the number 7, your task is to say the number that was presented 2 numbers before it. 4 8 3 7 8 2 5 6 7 8 0 2 4 6 7 N-BACK TASKS Correct responses: 8, 5, and 4 Was that difficult? For most people, these tasks are very challenging! Requires active maintenance of different items in working memory Target numbers (e.g., 7) Last 2 numbers Requires close attention! The larger the N, the more difficult the task Used to evaluate the functioning of an individual’s working memory GOAL SETTING AND PLANNING Central executive: Keeps track of goals Plans how to achieve them Determines priorities How do researchers examine these processes? Tower of Hanoi  TOWER OF HANOI Move all disks from the leftmost peg to the rightmost peg Move one disk at a time A larger disk cannot be placed on a smaller disk TASK SWITCHING Central executive: Paying attention to current active task Monitoring cues for information to switch to another task Example: listening to this lecture “Hey, this will be on the exam!!”  switch to paying attention How to researchers examine these processes? Wisconsin Card Sorting Test  WISCONSIN CARD SORTING TEST Participants are shown cards that differ in 3 characteristics Number, color, and shape Participant has to learn how the cards should be grouped together (i.e., the rule) After learning the rule, the rule changes Participant has to sort the cards based upon the new rule, not the previously learned rule WISCONSIN CARD SORTING TEST STIMULUS SELECTION AND RESPONSE INHIBITION Central executive: Directs attention to relevant stimuli Inhibits inappropriate automatic responses How do researchers examine these processes? The Stroop task THE STROOP TASK Let’s try this out! The next slide will have a list of words. Say the colors of each word aloud as quickly and as accurately as you can. Blue Red Yellow Green Black Blue Orange Red Green Black Blue Yellow Purple THE STROOP TASK Now we’re going to do it again, except the words are going to look a bit differently this time. Again, say the colors of the words as quickly and accurately as possible! Blue Red Yellow Green Black Blue Orange Red Green Black Blue Yellow Purple THE STROOP TASK The second time around was probably harder for you! Why? Task requires selective attention and inhibition Attend to the color of the word Inhibit reading the actual word Automatic vs. controlled responses WORKING MEMORY AND INTELLIGENCE Intelligence: The capacity for learning, reasoning, and understanding Less to do with processing speed and more to do with executive control N-back tasks related to intelligence Other measures of working memory related to SAT scores BRAIN SUBSTRATES  REVIEW OF IMPORTANT BRAIN AREAS Prefrontal cortex (PFC): Frontal lobe Critical for working memory and executive control BEHAVIOR CHANGES FOLLOWING FRONTAL-LOBE DAMAGE Remember Phineas Gage? Behavior drastically changed after damage to PFC Impulsive and erratic behavior He experience central executive damage Dysexecutive syndrome: disrupted ability to think and plan DEFICITS IN WORKING MEMORY FOLLOWING DAMAGE Deficits on all cognitive-control tasks Can’t remember lists of letters Can’t complete the Tower of Hanoi Can’t switch tasks in the Wisconsin Card Sorting Test This is known as perseveration: failure to learn a new rule despite feedback indicating it is not correct DIVISIONS OF THE PFC 3 main regions: Orbital prefrontal cortex Medial prefrontal cortex Lateral prefrontal cortex: Dorsolateral prefrontal cortex (DLPFC) Ventrolateral prefrontal cortex (VLPFC) DLPFC & VLPFC highly involved in working memory and cognitive-control functions STUDIES OF FRONTAL BRAIN ACTIVITY DURING WORKING- MEMORY TASKS Much research conducted with primates Tasks similar to N-back used with macaque monkeys Gaze tasks Required to remember where they had seen a target object Required to remember what object they saw STUDIES OF FRONTAL BRAIN ACTIVITY DURING WORKING- MEMORY TASKS Much research conducted with primates Tasks similar to N-back used with macaque monkeys Gaze tasks Finding: different neurons fire at different times PFC: sustains activity in the presence of distractions DLPFC: control and maintaining representations of sensory stimuli MAPPING WORKING MEMORY ONTO PFC ANATOMY CLINICAL PERSPECTIVES THE PFC IN SCHIZOPHRENIA Individuals with schizophrenia display disturbances in working memory and executive control DLPFC is dysfunctional When tasks involve manipulation or updating information in working memory (e.g., N-back) THE PFC IN ADHD Dysfunction in PFC and connections Connection to cerebellum Connections to basal ganglia Decreased PFC activity Really? Those with ADHD unable to inhibit responses  STUDY GUIDE Know the modal model of memory, including each memory store and how information flows through the storage systems. Know what type of information is held in sensory memory and short-term (working memory). Know the duration and capacity of each. Know the difference between Sperling’s whole report and partial report procedure, including what this tells us about sensory memory Know the types of sensory memory Know the difference between photographic memory and eidetic imagery Know what rehearsal is and how it impacts our ability to remember information Know Baddeley’s working memory model; specifically, you should be able to describe the phonological loop, visuospatial sketchpad, and central executive including the functions of each and what type of processing occurs in each  STUDY GUIDE Know how much information we can hold without rehearsal Be able to describe the DNMS task Know each of the cognitive control behaviors performed by the central executive and which tasks are used to explore specific behaviors (you should also be able to explain each type of task) Know how damage to the central executive impacts behavior. Know what dysexecutive syndrome is. Know the 3 main regions of the PFC, as well as the 2 subdivions of the LPFC Be able to describe the Gaze Task Know how the PFC and DLPFC activate during working memory tasks Know the PFC brain regions associated with each part of Baddeley’s working memory model Know how PFC functioning is different in certain clinical populations, such as those with Schizophrenia and those with ADHD.