Memory

Chapter 10

Memory Reconstructing the past Memory and the power of suggestion In pursuit of memory The three-box model of memory The biology of memory How we remember Why we forget Autobiographical memories

Reconstructing the Past The Manufacture of Memory The Fading Flashbulb The Conditions of Confabulation

The Manufacture of Memory Memory

The capacity to retain and retrieve information. Memory is a reconstructive process. Recovering a memory is not playing a videotape.

Memory involves inferences that fill in gaps in recall. We are often unaware we have made such inferences.

Source Amnesia The inability to distinguish what you originally

experienced from what you heard or were told later about an event.

The Fading Flashbulb Some unusual, shocking or tragic events

hold a special place in memory. These memories were called Flashbulb

memories because the term captures the surprise, illumination & photographic detail that characterize them.

Even flashbulb memories have errors.

The Conditions of Confabulation Confabulation

Confusion of an event that happened to someone else with one that happened to you,

or a belief that you remember something when it never actually happened.

Confabulation is most likely when: You have thought about the event many

times. The image of the event contains many

details. The event is easy to imagine. You focus on emotional reactions to the

event rather than what actually happened.

Memory and the Power of Suggestion

The eyewitness on trial Children’s testimony

The Eyewitness on Trial Eyewitnesses are not always reliable. Factors which influence accuracy

Cross race identification Question wording

Crashed versus hit

Misleading information

Children’s Testimony Under what conditions are children

more suggestible? Being very young When interviewers expectations are clear When other children’s memories for

events are accessible

Children’s Testimony If asked if a visitor

committed acts that had not occurred, few 4-6 year olds said yes. 30% of 3-year olds said yes

When investigators used techniques taken from real child-abuse investigations, most children said yes.

Social Pressure, False Allegations

In Pursuit of Memory Measuring memory

Explicit memory Implicit memory

Models of memory

Explicit Memory Conscious, intentional recollection of an

event or of an item of information. Assessed through: Recall

The ability to retrieve and reproduce from memory previously learned material.

Recognition The ability to identify previously encountered

material.

Implicit Memory Unconscious retention in memory, as evidenced

by the effect of a previous experience or previously encountered information on current thoughts or actions. Assessed through: Priming

a person reads or listens to information and is later tested to see whether the information affects performance on another type of task.

Relearning compares the time required to relearn material with the

time used in the initial learning of the material.

The Three-Box Model of Memory Sensory memory: Fleeting impressions Short-term memory: Memory’s scratch pad Long-term memory: Final destination Parallel distributed processing (PDP)

model: an alternative model of memory in which knowledge is represented as connections among thousands of interacting processing units, distributed in a vast network, and all operating in parallel.

Three-Box Model of Memory

Sensory Memory: Fleeting Impressions

A memory system that momentarily preserves extremely accurate images of sensory information.

Pattern Recognition The identification of a stimulus on the basis of

information already contained in long-term memory.

Information that is not quickly passed to short term memory is gone forever.

Short-term: Memory’s Scratch Pad In the three-box model of memory, a limited capacity

memory system involved in the retention of information for brief periods; it is also used to hold information retrieved from long-term memory for temporary use.

Working memory A memory system which includes STM and mental processes

that control retrieval of information from LT memory and interpret that information appropriately for a given task.

Chunk Meaningful unit of information which may be composed of

smaller units.

The Value of Chunking You have 5 seconds

to memorize as much as you can.

Then, draw an empty chess board and reproduce the arrangement of pieces.

Long-term memory: Final Destination The memory system involved in the long

term storage of information One way information is organized is in

semantic categories (i.e., animals).

Conceptual Grid

Contents of Long-Term Memory Procedural memories

Memories for performance of actions or skills. “Knowing how.”

Declarative memories Memories of facts, rules, concepts, and events;

includes semantic and episodic memory. “Knowing that”

Examples include semantic and episodic memories.

Contents of Long-Term Memory

Semantic memories General knowledge, including facts, rules,

concepts, and propositions. Episodic memories

Personally experienced events and the contexts in which they occurred.

Serial-Position Effect The tendency for

recall of first and last items on a list and to surpass recall of items in the middle of the list.

The Biology of Memory Forming a memory involves chemical and

structural changes at the level of neurons. In short-term memory, changes within neurons

temporarily alter the neuron’s ability to release transmitters.

In long- term memory, long-term potentiation or a long-lasting increase in the strength of synaptic responsiveness occurs.

Most researchers believe this is the process underlying learning and memory yet exact biochemical and molecular changes still debated.

Consolidation Process by which a long-term memory

becomes durable and stable.

Locating Memories New brain imaging and testing shows us that:

During short-term memory tasks, areas of the frontal lobes show activity.

Long- term memory tasks, the hippocampus. Encoding of pictures and words, prefrontal

cortex and areas adjacent to the hippocampus. Procedural memories, specific changes to

cerebellum. Formation of long-term memories, cerebral

cortex.

Hormones and Memory Hormones released by the adrenal glands

during stress and emotional arousal enhance memory.

Moderate levels are optimal: memory can suffer if animals are given very high doses of adrenal hormones.

These may affect memory by stimulating an increase in the level of glucose in the bloodstream.

How We Remember Effective Encoding Rehearsal Mnemonics

Rehearsal Maintenance Rehearsal

Rote repetition of material in order to maintain its availability in memory.

Elaborative Rehearsal Association of new information with already

stored knowledge and analysis of the new information to make it memorable.

Deep Processing In the encoding of information, the

processing of meaning rather than simply the physical or sensory features of a stimulus.

Comparing Encoding Strategies

Mnemonics Strategies and tricks for improving

memory, such as the use of a verse or a formula. Examples include:

MDAS ROYGBIV Thirty days hath September…

Why We Forget Decay Replacement Interference Cue-dependent forgetting Psychogenic amnesia

Decay Decay Theory

The theory that information in memory eventually disappears if it is not accessed; it applies more to short-term than to long-term memory.

Forgetting Curve Herman Ebbinghaus

tested his own memory for nonsense syllables.

Forgetting was rapid at first and then tapered off.

Replacement The theory that new information entering

memory can wipe out old information. In one study, researchers showed subjects slides

of a traffic accident. The experimental group was mislead into thinking

there was a stop sign instead of a yield sign. Even after being debriefed on the purpose of the

study, subjects insisted that they really saw the stop sign (Loftus et al., 1978).

The new information which came from the researchers replaced what the subjects saw.

Interference Similar items interfere with one

another. Retroactive Interference

Forgetting that occurs when recently learned material interferes with the ability to remember similar material stored previously.

Proactive Interference Forgetting that occurs when

previously stored material interferes with the ability to remember similar, more recently learned material.

Cue-dependent Forgetting

The inability to retrieve information stored in memory because of insufficient cues for recall.

Physical state can be a memory cue. State-Dependent Memory

The tendency to remember something when the rememberer is in the same physical or mental state as during the original learning or experience.

Mood

The Repression Controversy Psychogenic Amnesia

The partial or complete loss of memory (due to nonorganic causes) for threatening information or traumatic experiences.

Repression In psychoanalytic theory, the selective

involuntary pushing of threatening or upsetting information into the unconscious.

When should we question recovered memories? If person says he or she has memories of

first year or two of life. If over time the memories become more

and more implausible. If therapist used hypnosis.

Autobiographical Memories Childhood amnesia: The missing years

Childhood Amnesia: The Missing Years Childhood Amnesia

The inability to remember events and experiences that occurred during the first two or three years of life.

Cognitive explanations Lack of sense of self Impoverished encoding A focus on the routine Different ways of thinking about the world