Thinking About Psychology:

The Science of Mind and Behavior 2e

Borrowed Charles T. Blair-Broeker

Randal M. Ernst

Memory

WHAT IS MEMORY?

3 Processes of Memory

• Encoding – process of getting information into the memory system– Ex. Encoding lines and dots at meaningful words

• Storage – retaining encoded information over time

• Retrieval – process of getting information out of memory storage

Stage Model of Memory (Shiffron & Atkinson)

Three Storage Systems

• Three distinct storage systems :

– Sensory Memory

– Short-Term Memory (includes Working Memory)

– Long-Term Memory

Sensory Memory

• Brief, initial coding of sensory information in the memory system

– Iconic store – visual information (1/4 to ½ of a second.. Pencil example)

– Echoic store – sound information (3-4 seconds)

• Information held just long enough to make a decision on its importance

George Sperling (1960)

• His experiment demonstrated that our visual sensory memory holds information for about half of a second.

4th ed pg 244

Short-Term Memory• Part of your memory system that contains

information you are consciously aware of before it is stored more permanently or forgotten.

• Stage of memory in which info from the sensory memory and the long term become conscious.

• Holds info for about 20 seconds– Decay– Interference

• Can retain the information as long as it is rehearsed to a certain capacity

MAGIC 7, +/- 2

• George Miller 1956

• Holds seven, plus or minus two, chunks of information

• Demonstration pg 246 (4th ed) with a partner, record your results.

Chunking

• Organizing information into meaningful units helps retain the info in short term memory

• More information can be encoded if organized into meaningful chunks.

Chunking

Take ten seconds to memorize the above line of letters.

Chunking

Take ten seconds to memorize the above line of letters.

Chunking

• Chunking can also require use of long term memory

• Chunking is used for phone numbers, social security numbers, credit card numbers…

New research on short term capacity

• Nelson Cowan (2001, 2005) says it’s more like 4 +/- 1. He says that researchers over estimated capacity because of the type of stimuli used, people can “chunk” the information together to help remember.

• Jeffrey Rouder (2008) used colored blocks on a computer screen. In his experiment participants could only hold 3-4 items in short term memory. Either way.. Chunking helps!

• Mrs. Hollington’s circle example

Short term/Working Memory

• Working memory is what you’re using when you engage in problem solving, reasoning, language comprehension..

• Short term focuses on simple processes such as rehearsing words and numbers.

Model of Working MemoryAlan Baddeley

http://www.gocognitive.net/interviews/alan-baddeley-working-memory

• Phonological – focuses on verbal material

• Visuospatial sketchpad – spatial/visual remembering the lay out of a room

• Episodic added in 2000 - dedicated to linking information across domains to form integrated units of visual, spatial, and verbal information with time sequencing (or chronological ordering), such as the memory of a story or a movie scene. The episodic buffer is also assumed to have links to long-term memory and semantic meaning.

• Central Executive- the supervisor that controls attention, integrates information, and manages the activities of the other parts

Long-Term Memory

• Relatively permanent and limitless storehouse of the memory system

• Holds memories without conscious effort

• Anything longer than 20 seconds

• In order for information to make it to long term memory it must be encoded in short-term memory,

Massed Practice/ “Cramming”

• Putting all rehearsal together in one long session

• Not very effective for encoding into long-term memory.

Distributed Practice/Spacing Effect

• Spreading rehearsal out in several sessions separated by period of time usually enhances the recalling of the information

• http://www.gse.uci.edu/docs/VlachSandhoferChildDevelopment.pdf

The more time spent on rehearsal, the more information one tends to remember.

Elaborative Rehearsal• Focusing on the meaning of the information to

help encode and transfer it to long-term memory.– Make sure you understand what you are

studying.– Actively question– Think about potential applications and

implications. – Relate the info to things you already know– Generate your own examples of the concept

Overlearning

• Continuing to rehearse even after it has been memorized

• Rehearsing past the point of mastery

• Helps ensure information will be available even under stress

Self-Reference Effect• Enhanced semantic

encoding of information that is personally relevant

• Making information meaningful to a person by making it relevant to one’s life

Visual Imagery• Using vivid images

enhances encoding.

Levels-of-Processing Framework

• Craik and Lockart

• Information processed at a deeper level is more likely to be remembered than information processed at a shallow level.

Mnemonic Device

• A memory trick or technique

• “Every good boy does fine” to remember the notes on the lines of the scale

• “People say you could have odd lots of good years” as a way to remember how to spell “psychology”

Method of Loci

• You associate items you want to remember with imaginary places

• http://www.studygs.net/memory/memloci.htm

Types of Information in Long-Term Memory

• Procedural – riding a bike, running… sometimes hard to explain.

• Episodic – long term memory of specific events or episodes, including the time and place.– Autobiographical

• Semantic memory – general knowledge, often you don’t remember where you learned it.

Two Dimension of Long-Term Memory

Explicit Memory

• Memory with awareness• Includes episodic and

semantic• Declarative Memories,

you can declare the information

Implicit Memory

• Memory without awareness.

• Procedural memory• They cannot be

consciously recollected but they affect your behavior and knowledge. – Close your eyes and type

“most zebras cannot be extravagant.”

– Now name the keyboard letters left to right on the bottom row.

Explicit Memory

• Memory of facts and experiences

• Processed through the hippocampus

Explicit Memories

Explicit Memories

Implicit Memory

• Memory of skills and procedures

• Processed through the cerebellum

Implicit Memories

Implicit Memories

Memory and the Hippocampus

• Damage to the hippocampus would result in the inability to form new explicit memories, but the ability to remember the skills of implicit memories

Memory and the Hippocampus

Organization of Information in Long-Term Memory

• Clustering – organizing information into related groups or clusters during recall.

• Try example 6.6 (4th ed pg 252) I will time you.

• Semantic Network Model – describes units of information organized in a complex network of associations

Retrieval activity

• Spend 3-5 seconds reading each sentence (6.7a pg 253)

• Cover the sentences and write as much you can remember about each, you do not have to write “can be used” each time.

• Turn the page (6.7b pg 254) and your paper over.

• Use the retrieval cues to write as many sentences as you can. Do not look back at the sentences you just wrote.

Retrieval

• The process of getting information out of memory storage

• Retrieval cue – clue, prompt, or hint

• Retrieval cue failure– Tip-of-the-tongue experience

Recall (free recall)

• Type of retrieval in which you must search for information that you previously stored

• No clues

• Example 6.6

• Essay, fill-in-the-blank, and short answer test questions test recall

Cued Recall

• Example 6.7

• Fill-in-the-blank, matching

Recognition

• Identifying the correct information from several choices

• Multiple choice and matching test questions test recognition

Serial Position Effect• Tendency to recall the first and last

items in a list more easily

• Primacy effect – the ability to recall information near the beginning of a list

• Recency effect – the ability to recall information near the end of a list

Primacy/Recency Effect

Context Effect

Encoding Specificity• To retrieve information

recreate the original learning conditions.

Context Effect• Enhanced ability to retrieve

information when you are in an environment similar to the one in which you encoded the information

Context Effect

Mood Congruence

• Positive moods evoke positive memories and negative moods evoke negative memories.

Flashbulb Memory

• Vivid, clear memory of an emotionally significant moment or event

• Can be personal memories or centered around a shared event

Forgetting

• Inability to remember information

Hermann Ebbinghaus (1850-1909)

• German psychologist• Memory: A Contribution to

Experimental Psychology (1885)• His goal was to see how much

information people forget over different lengths of time.

• He wanted to make sure that he was studying the memory and forgetting completely new material. – He created thousands of

nonsense syllables– He was his first subject.

Ebbinghaus continued

• Noted how many times he had to repeat the list to memorize it.

• Once he learned it he tested his recall after varying amounts of time 20 minutes to 31 days.

• He then plotted the “forgetting curve”

Forgetting Curve• Most of what we forget is lost quickly

• How quickly we forget depends on several factors such as how well the material was encoded, how meaningful the material was, and how often it was rehearsed.

• The amount of forgetting levels off.

• The information not quickly forgotten seems to remain stable over long periods of time.

Why we forget1. Encoding failure – We never encoded the information into long

term memory.

Complete example 6.9 (Penny Test)

William Marmie & Alice Healey (2004) – Unfamiliar coin study confirmed the lack of attention at the time of encoding was responsible for failure.

Absentmindedness – you don’t pay attention when you should, your attention is divided.

Prospective Memory – remembering to do something in the future, you forget due to retrieval cue failure.

Why we forget

2. Decay Theory – we forget memories because we don’t use them and they fade away.

New memories form a memory trace- a distinct structural or chemical change in the brain. This contradicts Ebbinghaus, his forgetting curve states that forgetting stabilizes over time with the decay theory you would expect a steady decline.

We can also recall information that hasn’t been used for decades if given the right retrieval cues, this goes against the decay theory.

Why we forget

3. Interference Theory – One memory competes with or replaces another.

The more similar the information the more likely there will be interference.

Retroactive interference – new memory keeps you from remembering an old memory

Proactive interference – Old memory keeps you from remembering a new memory.

Why we forget4. Motivated Forgetting – we forget because the memory is disturbing or unpleasant.

Suppression - deliberate, conscious effort to forget.

Repression – forgetting that occurs unconsciously.

Freud believes repressed memories unconsciously effects our behavior.

Is the memory repressed or simply forgotten?

Some believe true repression doesn’t occur and others believe it is the root of many psychological problems.

Imperfect Memories

• Memory details can change over time.

• Details can be added, subtracted, exaggerated, or downplayed.

• Confidence in a memory does not guarantee accuracy.

Imperfect Memories

• A new memory is not simply recorded, it’s actively constructed.– You actively organize and encode information

(visual, auditory, tactile..)

• When you retrieve those details you reconstruct or rebuild the details of the memory.

• Through this process errors are likely.

Imperfect Memories

• Elizabeth Loftus (read intro story) – studied eyewitness memory and how it can go awry.

• Misinformation Effect – suggestive questions or information that person receives after an event can change what they remember.

Loftus and Palmer (1974)

• Misinformation Effect– Participants are exposed to a simulated

event, such as an automobile accident.– After a delay participants receive

misinformation, while half do not receive misinformation.

– Participants are asked to recall details about the original event.

Source Confusion• The true source of a memory is forgotten or

when a memory is contributed to the wrong source.

• It helps explain the misinformation effect: False details provided after the event become confused with the details of the original memory which create false memories.

• False Memories – distorted or fabricated recollection of something that did not happen.

The Impact of Existing Knowledge on What is Remembered

• Schemas – organized information about particular topics (object, setting, or concept). – Script: sequence of actions and behaviors at a common

event.– Schemas can promote memory errors by prompting us

to fill in missing details with schema-consistent information. (Professor’s Office example)

– Elements that are inconsistent with our schemas are better recalled.

• James Lampien’s story of Jack washing his car and taking the dog to the vet. Participants recalled inconsistent information better, but also created false memories about what would have been consistent with the script.

Forming False Memories• Loftus & Pickrell (1995) Lost in the Mall

– 24 participants were given information about 4 childhood events, one being a pseudoevent.

– Participants wrote down everything they could remember about each event.

– Participants were interviewed 1-2 weeks later and asked to recall details.

– 6 of 24 had created full or partial memories of being lost in the shopping mall.

– Lost-in-the-mall technique: using information from family members to create false memories of childhood experiences.

Forming False Memories

• Imagining the past different from what it was can change the way you remember it.

• Imagination Inflation: Vividly imagining an event increases confidence that the event actually occurred. – Vividly imagining helps the event seem familiar (false

familiarity)– Source Confusion, people may contribute the memory

of imagining the pseudoevent as being a memory of the actual event.

Biological Basis for Memory• Karl Lashley (1920s)

– Memory Trace (engram): brain changes that were to occur in forming a long term memory

– Searched for the specific location of the memory trace that a rat forms for running a maze. He suspected the specific memory would be at a specific site on the cerebral cortex.

– Once the rat learned the maze Lashley removed tiny portions of the cortex.

– He concluded that memories are not localized they are distributed and stored throughout the brain.

Biological Basis for Memory• Richard Thompson – 20 years after Lashley’s death

resumed research for the memory trace and found that some memories seem to be localized.

• Classically conditioned rabbits to blink to a tone after pairing the tone with a puff of air. When a portion of the cerebellum was removed the rabbit’s memory of the learned response disappeared, but the rabbit still blinked at the puff of air (reflexive).

• The long term memory trace of the blinking was stored in the cerebellum.

• Why had Lashley failed?

• Lashley and Thompson indicate that memories are both localized and distributed.– Simple memories are more localized– Complex memories are distributed– Brain imaging reveals when performing a

complex memory task multiple brain regions are activated

– Read “Focus on Neuroscience”

The Role of Neurons in Long-Term Memory

• Memory trace suggests that some change must occur in the brain when a long-term memory is formed. – The functioning of the brain’s neurons could change– Structure of the neurons can change– The challenge is to identify the specific neurons involved

in a given memory• Researchers have turned to Aplysia for the past 30 years+

• Eric Kandel (2001, 2006) studied the neuronal changes that occur when a new memory is formed for a simple classically conditioned response.– Increased amount of neurotransmitters– The number of interconnecting branches increases

Long-Term Potentiation

• Increase in synaptic strength

• Increase in a synapse’s firing efficiency that occurs when the sequence of neurons that represents a particular memory fires repeatedly

• Believed to be the neural basis of learning and memory

Processing Memories in the Brain

• Before brain imaging researchers studied those who had suffered a brain injury or had part of their brain removed. Many individuals experienced amnesia, or severe memory loss. (The Brain #18)

• Retrograde Amnesia – people are unable to remember some or all of their past. Typical for boxers and automobile accidents. Can’t recall their events preceding the injury.– Memory Consolidation: process of converting new, long term

memories to stable, enduring memory codes. (like Jell-O) This can be disrupted by brain trauma or encephalitis. Alcohol and benzodiazepines interfere with memory consolidation. Stimulants tend to enhance memory consolidation.

• Anterograde Amnesia: inability to form new memories

– Study of H.M. lasted over 50 years (Henry Molaison). When he was 27 years old in 1953 with a history of seizures, doctors located where the seizures seemed to originate. H.M.’s medial temporal lobe was removed on each side of Henry’s brain, including the hippocampus. H.M.’s seizure severity reduced. He could no longer form new long-term memories of events (episodic) or general knowledge (semantic).

– Brenda Milner and Suzanne Corkin studied H.M. He appeared normal with good vocabulary, normal intelligence, and a sense of humor. He lived in the eternal present.

– He could hold information in his short term memory for an hour or more with rehearsal. He could retrieve memories from before he was 16 years old.

– Sometimes he could recall some bits of information acquired after the surgery.

• Henry could not form new episodic or semantic memories, explicit memory system. He could form new procedural memories, such as solving a puzzle. He improved at solving the puzzle each day, but could not recall that he has seen the puzzle before.

Brain Structures Involved in Memory

• Cerebellum is involved in classically conditioning simple reflexes, and in procedural memories and other motor skill memories.

• Amygdala, is involved in encoding and storing emotional qualities of memories such as fear and anger.

• Frontal lobes are involved in retrieving and organizing info associated with autobiographical and episodic memories.

• Prefrontal cortex plays a role in working memory. • Medial Temporal lobe involved in encoding complex memories,

by forming links among the information stored in different brain regions.

Alzheimer’s Disease

• Dementia – broad term used to describe a decline and impairment of in memory, reasoning, language, and other cognitive functions. It is not a disease, it describes a group of symptoms that accompanies a disease or condition.

• The most common cause of dementia is Alzheimer’s Disease. (The Brain #19 & The Mind #17)

Alzheimer’s Disease

• Cause unknown• Patients develop an abundance of beta-

amyloid plaques and neurofibrillary tangles. – Plaques are deposits of protein and other cell

materials outside and around neurons interfering with the ability of neurons to communicate.

– Tangles are twisted fibers that build up inside the neurons and interrupt the flow of nourishment to the neuron, causing it to die.

Alzheimer’s Disease• Early stages: forgetting the names of familiar

people of places, forgetting to do things• Person becomes unable to remember what

month it is or the names of family members which leads to agitation.

• The last stage, internal brain damage is widespread. Doesn’t recognize anyone and cannot communicate in any meaningful way. All sense of self and identity are gone. It is fatal.

The End