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Unit II Chapter 4-Consciousness and its variations Chapter 6-Memory. Circadian Rhythm. Any rhythmic change that continues at close to a 24-hour cycle in the absence of 24-hour cues body temperature cortisol secretion sleep and wakefulness
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Unit II Chapter 4-Consciousness and its variations Chapter 6-Memory
Circadian Rhythm • Any rhythmic change that continues at close to a 24-hour cycle in the absence of 24-hour cues • body temperature • cortisol secretion • sleep and wakefulness • In the absence of time cues, the cycle period will become somewhat longer than 24 hours. • Where could there be an absence of cues?
Electroencephalogram (EEG) • Electrodes placed on the scalp provide a gross record of the electrical activity of the brain • EEG recordings are a rough index of psychological states
1 second Sleep stage 1 Sleep stage 2 Spindlers (bursts of activity) Sleep stage 4 Delta waves Stages of Sleep • Sleep stage 1: brief transition stage when first falling asleep • Stages 2 through 4 (slow-wave sleep): successively deeper stages of sleep • Characterized by an increasing percentage of slow, irregular, high-amplitude delta waves
Stages of Sleep • Upon reaching stage 4 and after about 80 to 100 minutes of total sleep time, sleep lightens, returns through stages 3 and 2 • REM sleep emerges, characterized by EEG patterns that resemble beta waves of alert wakefulness • muscles most relaxed • rapid eye movements occur • dreams occur • Four or five sleep cycles occur in a typical night’s sleep; less time is spent in slow-wave, more is spent in REM
Individual Differences in Sleep Drive • Some individuals need more and some less than the typical 8 hours per night • Nonsomniacs—sleep far less than most, but do not feel tired during the day • Insomniacs—have a normal desire for sleep, but are unable to and feel tired during the day
Sleep Disorders • Insomnia—inability to fall asleep or stay asleep • REM sleep disorder—sleeper acts out his or her dreams • Night terrors—sudden arousal from sleep and intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) • Narcolepsy—overpowering urge to fall asleep that may occur while talking or standing up. • Narcoleptic Dog • Sleep apnea—failure to breathe when asleep
Dreams and REM Sleep • True dream—vivid, detailed dreams consisting of sensory and motor sensations experienced during REM • Sleep thought—lacks vivid sensory and motor sensations, is more similar to daytime thinking • Lucid dreaming-Anyone know what this is? • Sleepwalking dog
Hypnosis • State of awareness • Highly focused attention • Increased responsiveness to suggestion • Vivid imagery • Willingness to accept distortions of logic • Alteration of sensation and perception
Meditation • Sustained concentration that focuses attention and heightens awareness • Lowered physiological arousal • decreased heart rate • decreased BP • Predominance of alpha brain waves
Psychoactive Drugs • Depressants—inhibit brain activity • Opiates—pain relief and euphoria • Stimulants—increase brain activity • Psychedelics—distort sensory perceptions
Common Properties • Physical dependence • Tolerance • Withdrawal symptoms • Drug rebound effect
Depressants • Alcohol—CNS depressant • Barbiturates—induce sleep • Tranquilizers—relieve anxiety
Opiates Chemically similar to morphine and have strong pain-relieving properties • Mimic the brain’s endorphins • Heroin, methadone • Percodan, Demerol
Stimulants • Caffeine • Nicotine • Amphetamines • Cocaine
Psychedelics • Create perceptual distortions • Mescaline • LSD • Marijuana • Flashback reactions and psychotic episodes
Maintenance Rehearsal Long-term memory Sensory Memory Working or Short-term Memory Encoding Attention Sensory Input Retrieval Three Stages of Memory • Three memory stores that differ in function, capacity and duration
Sensory Memory Sensory Input Sensory Memory • Function—holds information long enough to be processed for basic physical characteristics • Capacity—large • can hold many items at once • Duration—very brief retention of images • .3 sec for visual info • 2 sec for auditory info
Sensory Memory Working or Short-term Memory Sensory Input Attention Short Term or Working Memory
Sensory Memory Working or Short-term Memory Sensory Input Attention Short-Term Memory • Function—conscious processing of information • where information is actively worked on • Capacity—limited (holds 7+/-2 items) • Duration—brief storage (about 30 seconds)
Maintenance Rehearsal Sensory Memory Working or Short-term Memory Attention Sensory Input Maintenance Rehearsal • Mental or verbal repetition of information allows information to remain in working memory longer than the usual 30 seconds
Chunking • Grouping small bits of information into larger units of information • expands working memory load • Which is easier to remember? • 4 8 3 7 9 2 5 1 6 • 483 792 516
Maintenance Rehearsal Long-term memory Sensory Memory Working or Short-term Memory Encoding Attention Sensory Input Retrieval Long-Term Memory • Once information passes from sensory to working memory, it can be encoded into long-term memory
Maintenance Rehearsal Long-term memory Sensory Memory Working or Short-term Memory Encoding Attention Sensory Input Retrieval Long-Term Memory • Encoding—process that controls movement from working to long-term memory store • Retrieval—process that controls flow of information from long-term to working memory store
Types of Long Term Memory • Explicit memory—memory with awareness; information can be consciously recollected; also called declarative memory • Implicit memory—memory without awareness; memory that affects behavior but cannot consciously be recalled; also called non-declarative memory
Explicit Memory • Declarative or conscious memory • Memory consciously recalled or declared • Can use explicit memory to directly respond to a question • Two subtypes of explicit memory
Episodic Memory • Memory tied to your own personal experiences • Examples: • What month is your birthday? • Do you like to eat caramel apples? • Q: Why are these explicit memories? • A: Because you can actively declare your answers to these questions
Semantic Memory • Memory not tied to personal events • General facts and definitions about the world • Examples: • How many tires on a car? • What is a cloud? • What color is a banana?
Semantic Memory • Q: Why are these explicit memories? • A: Because you can actively declare your answers • Important note: Though you may have personal experience with these items, your ability to answer does NOT depend on tying the item to your past • i.e., Do not have to recall the time last week when you ate a banana to say that bananas are yellow
Tip of the tongue phenomenon • TOT—involves the sensation of knowing that specific information is stored in long-term memory but being unable to retrieve it • Can’t retrieve info that you absolutely know is stored in your LTM
Measures of Retrieval • Recall—test of LTM that involves retrieving memories without cues, also termed free recall • Cued recall—test of LTM that involves remembering an item of information in response to a retrieval cue • Recognition—test of LTM that involves identifying correct information from a series of possible choices. • Serial position effect—tendency to remember items at the beginning and end of a list better than items in the middle.
Eyewitness Testimony • Scripts—type of schema • Mental organization of events in time • Example of a classroom script: Come into class, sit down, talk to friends, bell rings, instructor begins to speak, take notes, bell rings again, leave class, etc.
Eyewitness Testimony • Recall not an exact replica of original events • Recall a construction built and rebuilt from various sources • Often fit memories into existing beliefs or schemas • Schema—mental representation of an object, scene or event • Example: schema of a countryside may include green grass, hills, farms, a barn, cows, etc.
Encoding Failures Even though you’ve seen thousands of pennies, you’ve probably never looked at one closely to encode specific features
Retroactive Interference • When a NEW memory interferes with remembering OLD information • Example: When new phone number interferes with ability to remember old phone number
100% Average percentage of information retained 20 mins 1 hr 8 hrs 24 hrs 2 days 6 days 31 days Interval between original learning of nonsense syllables and memory test Decay Theories • Memories fade away or decay gradually if unused • Time plays critical role • Ability to retrieve info declines with time after original encoding
Biological Basis of Memory • Amnesia—severe memory loss • Retrograde amnesia—inability to remember past episodic information; common after head injury; need for consolidation • Anterograde amnesia—inability to form new memories; related to hippocampus damage Memory test
MEMORY TEST CONCLUSION How many of you on the first list put down the word “SWEET”, if so stand up, good job. Now on the 2nd list, how many of you put down the word “ANGER” or “ANGRY”, if so stand up, good job. ALL OF YOU STANDING ARE 100%, POSITIVELY ?