Psych 120. General Psychology 7/12/2010. In the last lecture we learned about

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1 Psych 120 General Psychology Christopher Gade Office: 1030A Office hours: MW 4:30-5:30 Class MW 1:30-4:30 Room 2240 In the last lecture we learned about How memory was first studied. Memory testing techniques. Different types of memories Temporal Content specific Today, we re going to discuss how our memories can be erroneous at times. Problems with our memories Interference Serial order effects Reconstruction effects How to improve our memories Levels of processing Encoding specificity Learning intervals Mnemonic devices 1

2 Let s Test Our Memories We ll be going over several lists of words. Please follow the instructions and try to the best you can in each activity. Problems with our memories Interference: a loss of memory accuracy that is due to an overlap of information when trying to recall specific details of lists/events/people. Proactive interference: new material is lost (not easily stored) due to old material. Flowers New addresses (zip codes) Retroactive interference: old material is lost (forgotten) due to new material. Fruits Specific details about ex s Problems with our memories (cont.) Serial order (position) effect: the better retention of information/items due to their position in a list of information/items. Primacy effect: the ability to remember information at the beginning of a list more easily. Word lists 1 & 3 (primacy effect) Word list 2 (primacy effect removed) Recency effect: the ability to remember information at the end of a list more easily. Word lists 1 & 2 (recency effect) Word list 3 (recency effect removed) 2

3 Problems with our memories (cont.) Reconstruction effect: our tendency to include inaccurate information into our memories in an attempt to fill in the gaps. Reconstructing stories and adding details Subway video Word list 4 Note: This happens a lot more than we think it does! Creating false memories versus uncovering of forgotten memories Freud s work on repression Elizabeth Loftus research (in the text) Hindsight bias I remember thinking that today would not be my day. I never really liked him/her much anyway. I knew we shouldn t have invested in that company. How do we improve our memories? Let s try something out Task 1 In this task, you ll see a list of words, remember how many of these words have at least three vowels in them. 3

4 Task 1 In this task, you ll see a list of words, remember how many of these words rhyme with the word stack. Task 1 In this task, you ll see a list of words, remember how many of these words relate to something that you valued from your past. Mouse Shore Flight Shack Sheet Kayak House Attack Assure Unpack Blouse Smack 4

5 How to improve our memories (cont.) Levels of processing: The deeper you think about something, the more likely you are to remember the information. More time spent on the information More retrieval cues are available More neural connections are formed How to improve our memories (cont.) Encoding specificity: we re more likely to remember information when we are in a condition that resembles the condition that we were in when we learned the information. Mood dependency Recollection of traumatic events Situation dependency Baddelley s scuba diving experiment State dependency When you re using caffeine When you re using alcohol? How to improve our memories (cont.) Increased learning intervals Allows for deeper processing Counteract proactive and retroactive interference Allow for more encoding specificity opportunities Mnemonic devices THE mnemonic device EGBDF OCEAN Chunking Phone # s List #1 Information pairings List #2 Method of loci Grocery Lists 5

6 So what have we learned? We learned about how our memories can go awry at times. We also learned about a few methods that we can use in order to improve our memories. We learned that studying memory can be fun!!! Sleep In this part of today s lecture, we re going to talk about one type of altered consciousness sleep. We ll first discuss why we sleep. Biological theories Evolutionary theories Cognitive theories Then we ll cover what causes us to become tired. After that, we ll discuss the different stages of sleep. 6

7 The Purpose of Sleep The Repair and Restoration Theory: The purpose of sleep is to enable the body to recover from the exertions of the day. But what needs to recover??? Muscles Brain systems The Randy Gardner exception The Evolutionary Theory: Evolution equipped us with a regular pattern of sleeping and waking for the same reason to conserve fuel and to prevent us from walking into dangers. What would the purpose of functioning at night be? Little visual capabilities Scarce resources and opportunity to find food. Dangerous predators A huge amount of energy is required to maintain alertness and to function well in the night environment. What about today s world? Lighting is available Resources are abundant Fewer/no predators Equal amounts of energy are required in both day and night in order to maintain alertness and function well in the night Does this difference support or refute the evolutionary theory? Information Consolidation Theory: Our need for sleep is a result of the brain s need to consolidate the information obtained throughout the day into memories. What s the proof? High levels of brain activity during sleep Increased levels of learned responses Ferret maze experiment Is there any proof against this theory? Memories can obviously be established without sleep Brain activity measures taken during human sleep seem extremely random. 7

8 What causes us to become tired? One of the main causes of our sleep pattern is based on our circadian rhythms Circa: about a day Circadian rhythms effect our heart rate, body temperature, and brain functioning Looking at uncommon situations involving sleep tells us a lot about how our body functions The cave experiment Note: this tells us that Our bodies are also influenced/ reset by the sun every day. Question: How does this impact the biological or psychological debate about sleep? What happens while we sleep? In the mid 1950 s researchers discovered that during sleep, people display an extremely unusual pattern of behavior several times throughout the night. REM (rapid eye movement) or paradoxical sleep. Question: 1950 s??? From this REM discovery, researchers began observing and defining the different sleep cycles that we go thorough. Measures of Sleep EEG (electroencephalograph) Polysomnograph Video recordings Intermittent waking fmri 8

9 The Stages of Sleep Sleep stages 1 Awake REM Hours of sleep Stage 1 brain waves patterns that closely resemble waking patterns. Attentive to outside stimuli and can easily be woken. Will report still being awake when woken in this stage. Later replaced by REM sleep after the first sleep cycle of the night. Stage 2 Brain waves begin emitting sleep spindles. These spindles are random bursts of high amplitude EEG waves. People woken in this stage report having been asleep. Dreams can also occur in this stage, but they are rare. This stage makes up the majority of our sleep after the first two sleep cycles that we go through in a night. 9

10 Stage 3 This stage is represented by very slow and erratic brain waves. This is commonly the deepest level of sleep most people will get after people go through their first two stages of sleep. Believed to have some form of recuperative effect on the body. Stage 4 The deepest level of sleep that we encounter. It is represented by long, slow waves on EEG measures. Very difficult to wake people in this stage. The stage of sleep that a lot of little children are in while they sleep walk. Occurs only in the first (or first two) cycle(s) of sleep. Considered THE recuperative stage of sleep for our bodies. AKA paradoxical sleep Stage 5 (REM) The majority of our body is paralyzed during this stage. However, some body parts (eyes) are highly active. REM sleep and stage 2 sleep are the two most common stages of sleep after we experience our first two sleep cycles. Neural activity that resembles a waking state occurs during REM sleep. Associated with memory consolidation and emotion regulation. The majority of our dreams are believed to come from this stage. Waking experiments 10

11 Is this sleep cycle pattern the same across all ages? NO!!! As we age, or sleep patterns change immensely. In addition to that, the proportion of sleep stages varies widely depending upon the age of the person. Fetus Children Adults The Elderly What does this difference in sleep patterns across age tell us? It might give us insight into the function of different sleep patterns. It might tell us about the value and purpose of sleep. It might give us insight into the development of the brain. In truth, we really don t know exactly what this means. 11

12 On the Agenda In today s last section, we re going to discuss other forms of altered consciousness outside of the world of sleep. These forms of consciousness are Hypnotic induced states of mind Self induced states of mind Hypnotism Hypnosis: a condition of increased suggestibility that occurs in the context of a special hypnotist-subject relationship. Hypnotized people are in a state of great suggestibility. Hypnotized individuals give off the perception of being in a sleep-like state. Eyes often closed or only open a little Slow, lethargic behavior Brain waves of hypnotized individuals are reflective of the brain waves of people in a normal state of consciousness (less a few exceptions). 12

13 Franz Anton Mesmer ( ) First person to practice hypnotism. In his work as a philosopher and physician, he found that, when mesmerized, his patients were extremely open to suggestion and could reduce their sense of pain. Originally mesmerized people through the presentation of a magnet that was waved back and forth in front of his patients. Mesmer later found that this same effect could be obtained through the waving of his hand in a similar motion, which led him to conclude that he was magnetic. Note: this is where we get the term animal magnetism. Mesmer (cont.) Mesmer believed that this change in consciousness was caused by unblocking the flow of magnetic fluids. Believed that only he, and other special individuals were capable of mesmerizing (hypnotizing) individuals. Mesmer later went on to establish his own Magnetic Institute. He was eventually denounced as a fraud by the French medical establishment. What it takes to be hypnotized You need to believe that you can be hypnotized. You need to be in a relaxed state, and in a situation where there are no, or limited, distractions. While the hypnotist is hypnotizing you, you need to believe that you are being hypnotized. You re more likely to be hypnotized, and the effect will be much stronger if you are a suggestible individual. 13

14 Let s watch some examples of hypnotism 11:50 What can hypnotism do? Reduce emotional reactions to situations, this will result in a reduction in Sense of pain Tension Lack of concentration Small changes in stress related behaviors Create posthypnotic suggestions? A suggestion to do or experience something particular after coming out of hypnosis. Note: Questions remain about how long the effects of these posthypnotic suggestions last, people also question whether or not these suggestions would work for behaviors that we wouldn t do already. Create hallucinations (while hypnotized) maybe What can hypnotism not do? Improve our memories Repressed memories Allow us to travel into our past to recover memories Enhanced ability to learn information Note: hypnosis might be able to help increase our ability to remember things a little if we struggle to recall/store information due to emotional responses. Cause us to have supernatural physical abilities. stiff as a board I command you to walk Do something that we wouldn t do while in a normal state of consciousness. Maybe. 14

15 Other states of consciousness that are similar to hypnotism Meditation Calm, relaxed state that is very similar to arousal level of hypnotized individuals. Spiritual and social separation from the body Trance dancing (raves) Spiritual dance(s) Drug induced states You can read the previous chapter on neuroscience to learn more about specific drugs 15