VISUALIZING. Chapter 7: Memory. Lecture Overview. The Nature of Memory Biological Bases of Memory Forgetting Memory Distortions

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1 VISUALIZING Prepared By: Ralph Hofmann, Durham College Chapter 7: Memory Media Enhanced PowerPoint Presentation Copyright 2013 John Wiley & Sons, Canada Ltd 2 Lecture Overview The Nature of Memory Biological Bases of Memory Forgetting Memory Distortions Copyright 2013 John Wiley & Sons, Canada Ltd 3 1

2 The Nature of Memory LEARNING OBJECTIVES: 1. Review the principles of the two major memory models. 2. Describe the different purposes of sensory memory, short-term memory, and long-term memory. 3. Understand the relationship between short-term and working memory. 4. Identify the ways of extending the duration and capacity of short-term memory. 5. Describe the various types of long-term memory. 6. Explain how organization, elaborative rehearsal, and retrieval cues improve long-term memory. Copyright 2013 John Wiley & Sons, Canada Ltd 4 The Nature of Memory Memory An internal record or representation of some prior event or experience Constructive and re creative process We actively organize and shape information Copyright 2013 John Wiley & Sons, Canada Ltd 5 How Does Memory Work? Copyright 2013 John Wiley & Sons, Canada Ltd 6 2

3 Information Processing Model Information goes through three basic levels of processing by the brain Encoding Sensory information is converted to a neural code Storage In the appropriate area of the brain Retrieval Searches for stored files and brings them back into short term memory Copyright 2013 John Wiley & Sons, Canada Ltd 7 Information Processing Model Copyright 2013 John Wiley & Sons, Canada Ltd 8 Selective or Focused Attention Information gets in to be encoded because we pay attention to something Focused awareness is when we direct at some object or event while tuning out everything else Elective attention We tend to process information at a deeper level and enhance memory Divided attention Results in attentional multitasking in which neither task gets adequate attention Copyright 2013 John Wiley & Sons, Canada Ltd 9 3

4 Three-Stage Memory Model Memory comprises three different storage boxes or memory stages Each has a different purpose, duration and capacity Storage boxes Sensory Short term Long term Copyright 2013 John Wiley & Sons, Canada Ltd 10 Three-Stage Memory Model Copyright 2013 John Wiley & Sons, Canada Ltd 11 Sensory Memory: First Impressions First stage Everything we see, hear, taste and smell first enters sensory memory Large capacity but only lasts a few seconds If we attend to new information, it moves on to short term memory Copyright 2013 John Wiley & Sons, Canada Ltd 12 4

5 Iconic versus Echoic Memory Iconic memory Visual information lasts around 0.5 seconds Echoic memory Auditory memory lasts the same Weaker echo can last up to 4 seconds Copyright 2013 John Wiley & Sons, Canada Ltd 13 Sperling s Experiment with Sensory Memory When flashed an arrangement of 12 letters for 1/20 of a second, most people can only recall 4 or 5. Sperling proved all 12 letters were available in sensory memory if they can be attended to quickly. Copyright 2013 John Wiley & Sons, Canada Ltd 14 Short-Term Memory Also thought of as working memory Temporarily stores and processes sensory stimuli that has been attended to If it meaningful, it will be sent to long term memory Capacity limited to seven items (plus or minus two) Duration lasts about 30 seconds Copyright 2013 John Wiley & Sons, Canada Ltd 15 5

6 Improving Short-Term Memory Chunking Grouping separate pieces of information together into a single unit or chunk Telephone numbers, credit cards, etc. Increases capacity Maintenance rehearsal Repeating information to keep it active and reverberating in short term memory Increases duration Copyright 2013 John Wiley & Sons, Canada Ltd 16 Components of Short- Tem Memory Central executive Supervises and coordinates two subsystems Visuospatial sketchpad Mentally images visual and spatial material Phonological loop Rehearses through speech, words and numbers Copyright 2013 John Wiley & Sons, Canada Ltd 17 Components of Short- Term Memory Copyright 2013 John Wiley & Sons, Canada Ltd 18 6

7 Long-Term Memory Stores information for long periods of time Capacity is limitless Duration is relatively permanent Several types exist but there are two major systems of long term memory Explicit/declarative Implicit/nondeclarative Copyright 2013 John Wiley & Sons, Canada Ltd 19 Explicit/Declarative Refers to intentional learning or conscious knowledge Semantic memory Memory for general knowledge, rules, facts and specific information Episodic Mental journal of personal experiences May be short lived and others may last a lifetime Copyright 2013 John Wiley & Sons, Canada Ltd 20 Implicit/ Nondeclarative Non conscious learning or acquiring knowledge unintentionally Procedural motor skills Classically conditioned responses Fears, phobias, or taste aversions Priming Prior exposure to a stimulus inhibits the processing of new information Copyright 2013 John Wiley & Sons, Canada Ltd 21 7

8 Types of Long-Term Memories Copyright 2013 John Wiley & Sons, Canada Ltd 22 Improving Long-Term Memory Organization Rehearsal or repetition Effective retrieval Copyright 2013 John Wiley & Sons, Canada Ltd 23 Organization To successfully encode information, we need to organize it into hierarchies Arrange related items into broad categories that are further divided and subdivided Similar to chunking Takes time and effort Copyright 2013 John Wiley & Sons, Canada Ltd 24 8

9 Rehearsal Improves encoding for both STM and LTM Elaborative rehearsal Deeper level of processing required for LTM Links new information to previously stored material Immediate goal is to understand the material better Copyright 2013 John Wiley & Sons, Canada Ltd 25 Elaborative Rehearsal Understanding and memory may be enhanced by elaborating on previously known information Using knowledge of geography to better understand history Copyright 2013 John Wiley & Sons, Canada Ltd 26 Retrieval Effective retrieval is critical to improving LTM Retrieval cues A cue or prompt that helps stimulate retrieval Specific cues Requires only that you recognize the required response General cues Requires search through all possible matches Much more difficult task Copyright 2013 John Wiley & Sons, Canada Ltd 27 9

10 Recall versus Recognition Memory Recall tasks such as an essay question are much more difficult A recognition task such as multiple choice tend to be easier Copyright 2013 John Wiley & Sons, Canada Ltd 28 Longevity and Recognition Memory Both name and picture recognition for high school classmates remain high many years after graduation Recall memory would be expected to drop Copyright 2013 John Wiley & Sons, Canada Ltd 29 Mnemonic Devices Method of loci Attach different pieces of information to a location e.g. walk through a garden Peg words Attach items to images or pegs Copyright 2013 John Wiley & Sons, Canada Ltd 30 10

11 Mnemonic Devices Acronyms Create a new code word from the first letters of the items you want to remember, e.g., the Big Five personality traits (see Chapter 12): Openness Conscientiousness Extroversion Agreeableness Neuroticism = OCEAN Copyright 2013 John Wiley & Sons, Canada Ltd 31 Retrieval One important contextual cue is location Encoding specificity principle Retrieval of information is improved when the conditions of recovery are similar to the conditions of encoding Mood congruence People learn better if their moods during encoding and retrieval match Copyright 2013 John Wiley & Sons, Canada Ltd 32 Biological Bases of Memory LEARNING OBJECTIVES: 1. Describe two kinds of biological changes that occur when we learn something new. 2. Identify the primary brain areas involved in memory. 3. Explain how injury and disease can affect memory. Copyright 2013 John Wiley & Sons, Canada Ltd 33 11

12 Biological Bases of Memory Repeated practice builds specific neural pathways Long term potentiation Long term increase in neural excitability caused by repeated neural input Believed to be the basis of learning and memory Copyright 2013 John Wiley & Sons, Canada Ltd 34 Long Term Potentiation Repeated stimulation of a synapse causes more dendrites to grow more spines Strengthens the synapse More sensitive because action potential can affect more downstream neurons Learning affects a particular neurons ability to release neurotransmitters Copyright 2013 John Wiley & Sons, Canada Ltd 35 Hormonal Changes and Memory Emotional arousal often leads to stronger memory Release fight or flight hormones Affect the amygdala which signals the hippocampus and cerebral cortex Flashbulb memory Vivid images of circumstances associated with surprising or strongly emotional events Copyright 2013 John Wiley & Sons, Canada Ltd 36 12

13 Where Are Memories Located? Memories housed in a vast network of associations located throughout the brain More of a process than an anatomical structure Copyright 2013 John Wiley & Sons, Canada Ltd 37 Brain and Memory Formation Amygdala Emotion and memory Basal ganglia Creation and storage of basic memory, trace and implicit memories Hippocampal formation Memory recognition, implicit, explicit, spatial, episodic memory, sequence of events Cortex Encoding of explicit memories, storage of episodic and semantic memories, skill learning, working memory Copyright 2013 John Wiley & Sons, Canada Ltd 38 Injury, Disease and Memory Loss Traumatic brain injury (TBI) occurs when an external force injuries the brain Damage caused by compression, twisting, penetration or distortion Usually caused by falls, car crashes and misadventure Amnesia is a common outcome Loss of memory as a result of brain injury or trauma Copyright 2013 John Wiley & Sons, Canada Ltd 39 13

14 Amnesia Retrograde amnesia Amnesia for events that occurred just before an injury Thought to be caused by a failure of consolidation Usually temporary Anterograde amnesia Most commonly caused by surgical damage or disease Cannot form new memories Copyright 2013 John Wiley & Sons, Canada Ltd 40 Amnesia Copyright 2013 John Wiley & Sons, Canada Ltd 41 Alzheimer s Disease Progressive mental deterioration characterized by memory loss Note the reduced activity in the temporal and parietal lobes in the PET scan on the left Copyright 2013 John Wiley & Sons, Canada Ltd 42 14

15 Forgetting LEARNING OBJECTIVES: 1. Describe Ebbinghaus research on learning and forgetting. 2. Outline five key theories of why we forget. 3. Explain the factors that contribute to forgetting. Copyright 2013 John Wiley & Sons, Canada Ltd 43 Ebbinghaus Research Calculated how long it to learn and remember a list of three letter syllables Plotted forgetting curve Found that forgetting occurs most rapidly after learning Relearning is a faster process than learning Copyright 2013 John Wiley & Sons, Canada Ltd 44 Ebbinghaus Research Copyright 2013 John Wiley & Sons, Canada Ltd 45 15

16 Theories of Forgetting Decay Interference Encoding failure Retrieval failure Motivated forgetting Copyright 2013 John Wiley & Sons, Canada Ltd 46 Theories of Forgetting Decay Memory degrades over time Skills and memory degrade if they go unused Interference Forgetting is caused by two competing memories One memory interferes with the other Retrograde interference New information interferes with old Proactive interference Old information interferes with new Copyright 2013 John Wiley & Sons, Canada Ltd 47 Theories of Forgetting Motivated forgetting Motivation to forget unpleasant, painful of embarrassing memories Encoding failure LTM does not encode information as it passes from STM Retrieval failure Memories in LTM are momentarily inaccessible Tip of the tongue phenomenon Copyright 2013 John Wiley & Sons, Canada Ltd 48 16

17 Errors in Remembering Misinformation effect Serial position effect Source amnesia Sleeper effect Spacing of practice Copyright 2013 John Wiley & Sons, Canada Ltd 49 Errors in Remembering Misinformation effect Distortion of a memory by misleading post event information Experimenters created false memories in subjects by showing them doctored photos or asking them to imagine a fictitious event Serial position effect Subjects remember words at the beginning of a list (primacy effect) and at the end of the list (recency effect) Copyright 2013 John Wiley & Sons, Canada Ltd 50 Errors in Remembering Source amnesia Forgetting the source of the information due to overload Removes the context from the memory Sleeper effect When we hear information from an unreliable source, it is easy to discount it If the source of the information is forgotten, it is more likely to be accepted Copyright 2013 John Wiley & Sons, Canada Ltd 51 17

18 Errors in Remembering Spacing of Practice When we try to learn too much at once, we learn and remember less Distributed practice Spacing learning periods with rest periods between sessions Massed practice Cramming Copyright 2013 John Wiley & Sons, Canada Ltd 52 Memory Distortions LEARNING OBJECTIVES: 1. Explain why our memories sometimes become distorted 2. Describe the dangers of relying on eyewitness testimony 3. Summarize the controversy surrounding repressed memories Copyright 2013 John Wiley & Sons, Canada Ltd 53 Memory Distortions We shape, rearrange and distort our memories for a variety of reasons Need for logic and consistency Fill in the missing pieces, make corrections and rearrange information For the sake of efficiency Summarize, augment and tie new information in with old memories Copyright 2013 John Wiley & Sons, Canada Ltd 54 18

19 Memory and the Criminal Justice System Errors in memory can lead to wrongful judgements of guilt or innocence Occasionally life or death decisions Two general sources of problems Eye witness testimony Repressed memory Copyright 2013 John Wiley & Sons, Canada Ltd 55 Memory and Eyewitness Testimony Tends to be persuasive but often flawed Research has shown that it was relatively easy to influence eyewitness accounts and create false memories Judges now Allow expert testimony on the unreliability of eye witness testimony Routinely instruct jurors on its limits Copyright 2013 John Wiley & Sons, Canada Ltd 56 Eyewitness Testimony Witnessing or being a victim of a violent crime is an extremely emotional event Emotional events tend to make stronger flashbulb memories Copyright 2013 John Wiley & Sons, Canada Ltd 57 19

20 Elizabeth Loftus Well known memory researcher Long described powerful childhood memories of finding her mother dead Later found to be other family members that found the body Copyright 2013 John Wiley & Sons, Canada Ltd 58 Repressed Memories Repression Supposed unconscious coping mechanism by which we prevent anxiety provoking thoughts from reaching consciousness Theories around repressed memories Consciously forgotten in effort to avoid pain of retrieval Memories so painful that they exist only in an unconscious corner of the brain Copyright 2013 John Wiley & Sons, Canada Ltd 59 Repressed Memory Criticisms Critics suggest that most people will have difficulty forgetting traumatic events Some thought that therapists inadvertently create false memories Debate Not all repressed memories are false Significant impact on criminal prosecutions, lawsuits etc. Copyright 2013 John Wiley & Sons, Canada Ltd 60 20

21 Web Links Exploratorium Memory Exploratorium The Meaning of Droodles Human Memory How does the mind store information? What kinds of memory do people have? How easy is it for you to remember certain things? In the following experiments, you can learn something about human minds. Human Memory Exploring Human Memory Short Term Memory Baddeley s model of working memory has proven especially fruitful for research on the brain areas involved. This model posits a central processor that coordinates the activity of two sub systems. Many brain imaging studies show high activity in the frontal lobe when this central processor is working. Multimedia Face Memory Game How is your memory for faces? Don t Forget! Playing games with memory Forgetting Fear Whether they're unexplained phobias or fears that stem from a bad experience, most of us are afraid of something. But can we ever get over our fears? Scientists are looking for the answer in our brains. This ScienCentral News video has more. Coffee Break Brain Here's a reason to tell your boss to "give you a break." As this ScienCentral News video explains, scientists working with rats say breaks from activities may help your memory. Copyright 2013 John Wiley & Sons, Canada Ltd 61 Web Links Making Memories Ever been in a spot where you can t put a name to a face or a face to a name? As this ScienCentral News video reports, neuroscientists have more information about what happens in the brain as these memories are made. Researchers Prove A Single Memory Is Processed in Three Separate Parts of the Brain UCI researchers have found that a single brief memory is actually processed differently in separate areas of the brain an idea that until now scientists have only suspected to be true. The finding will influence how researchers examine the brain and could have implications for the treatment of memory disorders caused by disease or injury. Multimedia Researcher Identifies Brain Activity That Sets the Stage for Retaining Memory Researchers have identified the neural activity that occurs when the brain sets the stage for retaining a memory a finding that could have important implications for memory research and help determine ways in which people can strengthen memories they want to retain while weakening ones they would rather forget. Sheep Brain Dissection The Anatomy of Memory Copyright 2013 John Wiley & Sons, Canada Ltd 62 Web Links Multimedia How The Brain Creates False Memories Lawyers are often suspicious of so called "eyewitness accounts" and rightly so. Hundreds of scientific studies in the past few decades have shown that the memories of people who observe complex events are notoriously susceptible to alteration if they receive misleading information about the event after it has taken place. In this month's issue of the journal Learning & Memory, scientists from Johns Hopkins University report new insights into how such "false memories" are formed. This is the first study to use neuroimaging to investigate how the brain encodes misinformation during the creation of a false memory. Can You Force Yourself to Forget? One psychologist says he's discovered a mechanism that could explain how people suppress unwanted memories; others disagree. False Food Memories If your first taste of potato chips or chocolate had made you sick, your eating habits today might be different. As this ScienCentral News video explains, psychology researchers suggest that changing memories about food could change what we choose to eat. Memory and Reality Some of our memories are true, some are a mixture of fact and fantasy, and some are false whether those memories seem to be continuous or seem to be recalled after a time of being forgotten or not thought about. Copyright 2013 John Wiley & Sons, Canada Ltd 63 21

22 Videos Brain Viagra, Part 2 (1:39) There s a huge market for substances that claim to boost memory, but when can we expect drugs designed and proven to do that? Drive Brain Power (1:39) Three years ago a study showed parts of the brain controlling learning and memory were bigger in London cab drivers' brains, to help store detailed mental maps of the city. Does it really take big brains to be a cab driver? Learning to Forget (0:54) Many Americans are still searching for ways to escape the anxiety caused by September 11th. Alzheimer s Scans (1:31) A new 3 D time lapse video technique is helping neuroscientists see the progression of Alzheimer s disease in patients brains for the first time. As this ScienCentral News video reports, it will help in early diagnosis and intervention. Multimedia Brain Pills (1:46) You may have used over the counter pills like ibuprofen for pain. Now neuroscientists have found that some of these common painkillers may be more useful than you think. Wiring the Brain (1:21) Interested in continuing education? Here's some good news. As this ScienCentral News video reports, brain researchers have uncovered one mechanism that controls how our brains make new connections. Memory Storage Video (1:33) The new movie Eternal Sunshine shows us a fictional way to erase the past, but what keeps those thoughts around in the first place? As the ScienCentral news video reports, brain researchers are beginning to unwind a new twist on maintaining memory. Copyright 2013 John Wiley & Sons, Canada Ltd 64 Animations Enhancing Memory Imagine that you are going to an interview for an important position as a human relations psychologist. Multimedia Copyright 2013 John Wiley & Sons, Canada Ltd 65 Copyright Copyright 2013 John Wiley & Sons Canada, Ltd. All rights reserved. Reproduction or translation of this work beyond that permitted by Access Copyright (The Canadian Copyright Licensing Agency) is unlawful. Requests for further information should be addressed to the Permissions Department, John Wiley & Sons Canada, Ltd. The purchaser may make back-up copies for his or her own use only and not for distribution or resale. The author and the publisher assume no responsibility for errors, omissions, or damages caused by the use of these programs or from the use of the information contained herein. Copyright 2013 John Wiley & Sons, Canada Ltd 66 22