Memory

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Transcript Memory

Chapter Six Memory

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Did You Know That…

• • A man was able to memorize lists of hundreds of meaningless syllables and recite them fifteen years later?

Some research subjects did better on a memory test when they were submerged in water?

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Did You Know That…

(cont.)

• • • Though most people can retain only about seven items in memory at any one time, you may be able to juggle sixteen, twenty, or more items in your mind by using a simple memory device?

A good way to retain information you’ve just learned is to sleep on it?

The World Wide Web was modeled on the way the human brain works?

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Did You Know That…

(cont.)

• • • People can be misled into believing they saw a yield sign at an accident scene when they actually saw a stop sign?

Fewer than half of the people tested in a research study could pick out the correct drawing of a penny?

If your hippocampus were removed, each new experience would come and go without any permanent trace left in your brain that the event ever happened?

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Module 6.1

Remembering

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Module 6.1 Preview Questions

• • • • • What are the basic processes and stages of memory?

What is the constructionist theory of memory?

What are flashbulb memories?

What factors influence the accuracy of eyewitness testimony?

Are recovered memories of childhood sexual abuse credible?

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What Is Memory?

• The system that allows us to retain information and bring it to mind.

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Figure 6.1: Three Basic Processes of Memory

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Memory Encoding

• • The conversion of information into a form we can store in memory.

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Memory Storage and Retrieval

• • Memory Storage: The process of retaining information in memory.

Memory Retrieval: The process of accessing and bring into consciousness information stored in memory.

– – Some memories retrieved effortlessly.

Retrieval cues often required to bring memories to awareness.

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Retrieval Cues

• • • Encoding Specificity Principle: Retrieval will be more successful when cues during recall are similar to those present at the time of encoding.

Context-Dependent Memory Effect: Setting context of learning serves as set of retrieval cues.

State-Dependent Memory Effect: Better recall when in same physiological or psychological state while learning/recalling.

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Figure 6.2: Context Dependent Memory Effect

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Three-Stage Model of Memory

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Sensory Memory

• • • Storage system that holds sensory information for a very short time.

– Held in the “sensory register” Iconic Memory: Sensory register for visual stimuli.

– George Sperling’s ( 1960) research – Eidetic imagery or photographic memory Echoic Memory: Sensory register for auditory stimuli.

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Short-Term Memory (STM)

• • • • Sensory memories are transferred into short term or working memory.

STM retains and processes information for up to 30 seconds.

Relies mostly on acoustic coding.

Holds information long enough for it to be actively worked on or processed by the brain.

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How Much Information Can STM Hold?

• • • • Remember these numbers: 6293 –

Now recall the numbers

73932 –

Now recall the numbers

835404 –

Now recall the numbers

3820961 –

Now recall the numbers

• • • 18294624 –

Now recall the numbers

9284619384 –

Now recall the numbers

1992199319941995 – –

Now recall the numbers Why were these numbers easier to remember?

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Storage Capacity of STM

• • Storage capacity is about 7 items, plus or minus 2.

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Figure 6.3: Three-Component Model of Working Memory

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Long-Term Memory (LTM)

• • Retains information beyond short term memory.

Consolidation: The process of converting short-term memories into long-term memories.

– – First 24 hours is critical.

Dreams occurring during REM sleep may play an important role.

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Transferring Information to LTM

• • • Depends on semantic coding or coding by meaning.

Elaborative Rehearsal: Focus on the meaning of material while rehearsing.

– Associate new material with familiar, meaningful information.

How is information in LTM organized?

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Figure 6.4: Semantic Network

Source:

Collins, A.M., & Quillan, M. R. (1969). Retrieval times from semantic memory. Journal of Verbal Learning and Verbal Behavior, 8, 240-247.

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Long-Term Memory: Levels-of-Processing

• • • How information is processed at determines how well or how long information is stored in memory.

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Figure 6.5: Three-Stage Model of Memory

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Figure 6.6: Types of Long-Term Memory

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Figure 6.7: Declarative Memory

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Reliability of Long-Term Memory

• • • Can we trust our memories?

Constructionist Theory: Memory is a reconstructive process.

– – Memories may be distorted.

Better recall for information consistent with existing memory schema.

Flashbulb Memories: Vivid, lasting, and highly detailed memories.

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Eyewitness Testimony

• • Can be flawed and mistaken.

– Misinformation effect Accuracy influenced by: – Ease of recall – – – – Degree of confidence Knowledge of a subject Racial identification Types of questions Copyright © Houghton Mifflin Company. All rights reserved.

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Figure 6.9: Misinformation Effect

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Recovery of Repressed Memories

• • • • Controversial issue Total lack of memory is rare, but possible such memories may be lost.

False memories have been induced in experimental studies.

But, are recovered memories genuine?

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Module 6.2

Forgetting

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Module 6.2 Preview Questions

• • • What are the major theories of forgetting?

How is recall related to the methods used to measure it?

What is amnesia, and what causes it?

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Decay (or Trace) Theory

• • Memories gradually fade and deteriorate over time.

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Figure 6.10: Ebbinghaus Forgetting Curve

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Decay Theory

(cont.)

• • • Savings Method: Compare number of trials need to learn material with number of trials needed to relearn the material at a later time.

Massed vs. Spaced Practice Effect – Massed practice (or cramming) causes mental fatigue that interferes with learning and retention.

Weakness of theory: Fails to account for unevenness of memory decay over time.

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Figure 6.11: Retroactive and Proactive Interference

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Minimizing Interference

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Serial Position Effect

• • • The tendency to recall items at the start of end of a list better than items in the middle of the list.

– Interference is likely explanation for effect.

Primacy Effect: Tendency to recall items better when they are learned first.

Recency Effect: Tendency to recall items better when they are learned last.

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Figure 6.12: What Image Appears on the Front of a Penny?

ANSWER: Drawing (h)

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Retrieval Theory

• • • Forgetting is the result of failure to access stored memory.

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Motivated Forgetting

• • • Sigmund Freud Repression: Threatening memories kept hidden from awareness.

– Traumatic experiences, unacceptable impulses, desires Problems with Freud’s concept of repression – – Doesn’t account for ordinary forgetting.

Traumatized people often retain vivid if somewhat fragmented memories of experience.

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Measuring Memory

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Amnesia

• • • Loss of memory Types – – – Retrograde amnesia Anterograde amnesia Childhood amnesia Causes – – Physical damage or disease Psychological: dissociative amnesia Copyright © Houghton Mifflin Company. All rights reserved.

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Module 6.3

The Biology of Memory

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Module 6.3 Preview Questions

• • • • Where are memories stored in the brain?

What is LTP, and what role do scientists belief that it plays in memory function?

What is the role of the hippocampus in memory?

What have scientists learned about the genetic basis of memory?

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Where Do Memories Reside in the Brain?

• • Karl Lashley’s (1890-1958) search for the engram – Term used to describe a physical trace or etching of a memory in the brain.

Lashley concluded memories scattered throughout the brain.

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Circuitry of Memory

• • PET scans and fMRI research Neuronal Networks: Memory circuits in the brain that consist of complicated networks of nerve cells.

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Figure 6.13: Brain Structures in Memory

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Connections Between Neurons

• • Kandel’s work with sea snail (Aplysia) Long-Term Potentiation (LTP) – Synaptic connections strengthened by repeated stimulation.

– May lead to conversion of STM into LTM.

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Genetic Bases of Memory

• • Gene regulation – Proteins necessary for making long-term memories.

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Module 6.4

Application: Powering Up Your Memory

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Module 6.4 Preview Question

• What can you do to power up your memory?

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Mnemonics

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General Suggestions for Memory Improvement

• • • • • • • • Pay attention Practice to overlearn External memory aids Link time-based tasks to external cues Mentally rehearse what intend to do Enhance context-dependent memory effects Control stress Adopt healthy habits Copyright © Houghton Mifflin Company. All rights reserved.

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