Cognitive processes memory

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Cognitive processes memory

  1. 1. Cognitive Processes: Memory
  2. 2. Hermann Ebbinghaus (1885) • He conducted the first major studies of memory, • Used himself as a subject and nonsense syllables, such as VOL, RIZ, and TAV, as a material to be learned • Measured both learning and retention Savings method or method of relearning: Hermann Ebbinghaus 1850-1909 • Refers to amount of time it takes to learn a list a second time • Original overlearning, or repeating the list of items will result in a saving of both time and errors upon relearning Nature of Forgetting: Initial drop-off followed by slower forgetting overtime • 63% of material is remembered after 20 minutes • 38% after one day • 31% after two days • 25% after 31 days
  3. 3. Forgetting Curve • Illustrates the decline of memory retention in time. • Strength of memory refers to the durability that memory traces in the brain. • The stronger the memory, the longer period of time that a person is able to recall it. Graph of the Forgetting Curve: Humans tend to halve their memory of newly learned knowledge in a matter of days or weeks unless they consciously review the learned materials
  4. 4. Multi-store Model Memory consists of three levels of systems: 1. sensory memory, 2. Short-Term Memory 3. Long-term Memory Sensory memory: • Sense organs have a limited ability to store information for less than a second • Provides brief storage of sensory information, after the stimuli have been removed • Echoic store: Sensory store (hearing system) for auditory information • iconic store; Sensory store for visual stimuli • Visual system processes visual stimuli such as shape, size, color and location, but not meaning
  5. 5. STM (working memory): • Has a limited capacity • sensory memory ___attention____ STM • Holds a limited amount of information for a short period of time • For example: - you keep some piece of information in your head for just a few seconds. - A number to do a subtraction, - an argument you make after a person finishing talking • Ability to hold on to a piece of information temporarily to complete a task. • It causes pre-frontal lobe to be very active.
  6. 6. George Miller (1956) • Identified "magical number of 7 plus or minus 2 as amount of information that can be retained in STM with rehearsal Chunking: • Increases the amount of information that can be retained in STM store • Involves grouping large amounts of information into smaller related units • For example, the mobile number: 966545074077 • 966 545 074 077 • The 7 units of information could be 7 sentences or 7 phrases, rather than 7 words or 7 letters
  7. 7. Long-term Memory (LTM): • Has an unlimited capacity • Information gets into LTM only if it is transferred from STM • This is related to how information is rehearsed • Once information is transferred to LTM, it remains there permanently, • May not remain if brain is compromised severely due to a medical condition or substance use
  8. 8. Atkinson and Shiffrin Model (1968) Multi-store model •12 items •George Sperling (1960) •Partial Report Paradigm 7±2 Miller’s Magic Number (1956)
  9. 9. 10 Information processing model Explanations for how cognitive processes work are known as information processing theories or models. The three- component model of information processing is taught in Educational Psychology. http://www.innovativelearning.com/educational_psychology/cognitivism/index.htm
  10. 10. Hippocampus: • Information is transferred from STM to LTM through hippocampus, • Resembles the curved tail of a seahorse • Old part of cortex, evolutionarily, and is located in the inner fold of the temporal lobe.
  11. 11. Endel Tulving (1986): • He divided LTM into three components: - Procedural - Semantic - Episodic Procedural memory (implicit): • LTM of motor skills, habits, and ways of doing things, such as drive a car • Recalled without conscious effort; • Acquired through observation and practice and are difficult to forget Semantic memory: • LTM of knowledge about language (e.g., what words mean and how they are used), • common sense, and the rules of logic and inference • Social customs Episodic memory (autobiographical memory): • Contains information about events that have been personally experienced • Links to time and place
  12. 12. • Semantic and episodic together are called “declarative memory” Declarative Memory (explicit): • Effortful • Factual Memory • Consciously Available Priming: • Unconscious and that is not episodic, procedure nor semantic • Instance of perception rather than memory • Its role is to enhance identification of objects so that they seem familiar • Exists when the appearance of fragments of a previously encountered target (eg, the first few letters, sketchy outline, first letter of a verse in the Quran) • Increase in ease of doing a task or remembering information as a result of a previous encounter with the task or information. ‫به‬ ‫يذكرني‬ ‫شي‬ ‫فيه‬ ‫بس‬ ‫اسمه‬ ‫ناسية‬ ‫أحد‬ ‫أشوف‬ ‫لما‬ ‫علةقة‬ ‫له‬ ‫مره‬ ‫بأول‬
  13. 13. • One with dissociative amnesia (psychogenic not biologically caused amnesia) displays Retrograde but not Antrograde amnesia • One sign of pseudodementia is Retrograde but not AA Global amnesia. • Some patients with severe cases have a combined form of anterograde and retrograde amnesia • Neuropsychologists debate over whether it is a problem with encoding or retrieval
  14. 14. Schema Theory of Memory: • Schema is a cognitive structure or framework that influences how we look at the world – basically, mental models of how things are • Wyer and Scull (1986) indicate that schema affects how we store and retrieve information • Our memory is filtered through schema • Witness testimony and other reported memories may be biased to fit into preexisting schema
  15. 15. Mnemonic Devices: • Strategies known as mnemonic devices improve memory for information •Method of Loci (ML(: • Loci" is the plural of locus, which means location, or place • Involves associating each item to be remembered with mental images of "places" • For terms that unrelated and difficult to remember, a visual image is most effective • Useful for remembering terms recalled in a specific order • To use ML, first mentally associate each item to be remembered with a visual image • Mentally place these images somewhere in a familiar room or building, such as in corners, and on tables and chairs
  16. 16. • To recall the items, you would mentally walk through the room or building and "look" around at the items • ML exemplifies the use of visual imagery as a tool for remembering verbal information • Visual imagery is highly effective as a memory aid • People who have the ability to form vivid visual images tend to be good at memorizing Here's how it would work if you wanted to remember the following shopping list: 1. Ketchup 2. ice cream • Enter the dining room and picture a bottle of ketchup, dressed in an Asian maid's uniform, sitting on the table. • Go to the kitchen and picture a gallon of ice cream, melting over a hot stove. • Or locate your car’s driver standing by your house door and visualize him wearing a cony hat of ice cream
  17. 17. Eidetic Imagery: ‫تخيلى‬ • In layperson's terms, it is called "photographic memory“ • Patient can study an image for approximately 30 seconds, and maintain a nearly perfect photographic memory of that image for a short time once it has been removed • Some people have an ability to remember very specific details • They have ability to recall images, sounds, or objects in memory with extreme accuracy and in abundant volume. • Able to maintain a mental picture of an object even after it is removed • More common in children than adults • Intensity of recall may be subject to several factors such as duration and frequency of exposure to the stimulus observation , relevance to the person, etc
  18. 18. Context and State Dependence: Encoding Specificity Hypothesis (Tulving &Thomson, 1973) • Indicates that the closer relationship between encoding, storage, and retrieval, the better the recall of information Context Dependence: • When the learning and retrieval environments are the same or similar, your recall of information will be better than when the two environments are different • For example, take exam in your own classroom State Dependence: • When your emotional state is the same during learning and retrieval, you will find it easier to remember information than when your emotional state differs • Being in a depressed mood increases tendency to remember negative events.
  19. 19. Environmental reinstatement effect (long-term vs. short-term) • Long-term: Even after many years of absence, go back to your primary school campus and you will immediately remember things that have already been forgotten • Short-term: Imagine sitting at your desk and deciding to get a drink from the kitchen. • Once you get to the kitchen, you completely forget what you wanted. • If you return to your desk, you will most likely remember what you wanted from the kitchen.
  20. 20. Hippocampus and prefrontal cortex • Hippocampus and prefrontal cortex are involved in context dependent memory. • fMRI demonstrated elevated activation in the hippocampus when contextual information matches from encoding to retrieval, suggesting that the hippocampus may be important in mediating context-dependent memory processes • Activation of the right prefrontal cortex was dependent on contextual information Hippocampus activation in context dependent state pre prefrontal cortex
  21. 21. Example of context dependent memory • Divers in underwater environment were placed under water and listened to a prerecorded list of 36 unrelated words. • After listening to the list of words they were tested on their recall of the words in: - the same environment - the alternative environment. • Results showed that: - words learned underwater were best recalled underwater, - words learned on land were best recalled on land.
  22. 22. Overlearning: • Refers to a person practicing or rehearsing of some material beyond the point of mastery • In learning information that has little inherent (‫)متأصل‬meaning such as multiplication table, overlearning is the most effective memory strategy • Overlearning is best for simple tasks
  23. 23. Forgetting: There are a number of theories of forgetting such as: A. Trace Decay: • Refers to information in LTM that are deteriorated or forgotten unless it is accessed or rehearsed • This explains the loss of information from STM B. Interference: Types of interference: 1. Retroactive inhibition (RI) • RI occurs when a new experience interferes with recall of an earlier one • For example, anatomy lecture of today interferes with information of anatomy lecture of last week. • So you experience difficulty recalling anatomy information of last week
  24. 24. Experimental vs. control group: • Experimental group learns list A and list B and recalls B. • Control group learns list B and is asked about recalling list B List A List B_________experimental group___control group orange okra learn A and B and learn B and banana biscuit recall A recall B grape garlic • Control group recall B better than experimental group. • Sleeping following the learning of new information demonstrate better recall than remaining awake after learning the same information 2. Proactive Inhibition (PI) • Occurs when previous learning interferes with more recent learning. • For example, anatomy lecture of last week interferes with information of anatomy lecture of today. • So you experience difficulty recalling anatomy information of today
  25. 25. C. Repression: • Information is not recalled due to its emotional significance • An active inhibition of recall, rather than a true loss of information, accounts for observed instances of forgetting • Repression of memory is seen as a dynamic and unconscious process • For example, a severe fright or trauma may be repressed because recall of trauma is disturbing • 19% of sexual abuse victims had forgotten but later recalled sexual abuse (loftus et al, 1994) Hypnosis: • Research shows that Memories retrieved under hypnosis tend to be less accurate than other memories • Nonetheless, Individuals who recall information while under hypnosis have greater confidence in their memories as compared to controls • In some research studies, hypnotized subjects were reluctant to admit that their memories were inaccurate even confronted with clear evidence demonstrating this to be the case
  26. 26. Anatomically Correct Dolls: Used for assessment of childhood sexual abuse and by parents of identifying inappropriate touching: 1. Sexual abuse victims do respond differently to these dolls than non victims (e.g., among victims sexualized play is more common) 2. Dolls facilitate memory for details of sexual abuse 3. Useful in helping shy, embarrassing, or verbally limited to talk children about incidents of abuse male/female identification (with depicted genitals) mom is going through her pregnancy CONTROVERSIAL
  27. 27. Metacognition: • Refers to thinking about thinking or knowing about knowing • Refers to person’s awareness about his or her own cognitive state and processes Metacognition involves: • Evaluating one’s own cognitive skills • Using strategies to increase the efficiency of memory or learning • The ability to determine how much knowledge you have and need • Using mnemonics in rereading or organizing information • Develops in early adolescence or later, in conjunction with Piaget’s formal operation stage • Found in adult intelligence
  28. 28. Zeigarnik Effect (1938) • Bluma Zeigarnik assigned her subjects simple puzzle-like problems • Subjects allowed to finish half the problems but interrupted and kept from finishing the other half • Later, subjects were asked to recall all tasks • 68% of unfinished tasks were recalled vs. 43% of finished tasks • Interrupting a subject in middle of task has the effect of leaving him or her in a state of tension and disequilibrium • To replace the tension, subject wants to complete the task, and thereby to remember unfinished tasks better than completed ones

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