MEMORYChapter 7, 19 (Bernstein), pages 237-277,

770-773

THE NATURE OF MEMORY

• The process of putting information into memory is called ENCODING.

• Sensory info is put into memory codes (mental representations of physical stimuli).

• ACOUSTIC ENCODING information as sequences of sounds

• VISUAL ENCODING information in the form of a picture

• SEMANTIC ENCODING the general meaning of information

• Holding information in memory over time is called STORAGE.

• RETRIEVAL pulling info out of memory and into consciousness after it’s been stored

• Recall retrieving info without any cues to help

• Recognition retrieving info with the aid of cues

Basic Memory Processes

THE NATURE OF MEMORY

At least 3 types of memory exist, each named for the type of information it handles.

1.EPISODIC MEMORY any memory of a specific event that happened while you were present

• e.g., your 13th birthday party, when you found out a close relative died, your first day of school at South Warren HS

2.SEMANTIC MEMORY memory which contains generalized knowledge of the world that does not involve memory of a specific event

• e.g., George W. Bush, the relative location of Canada, things to do in New York City

3.PROCEDURAL MEMORY memory of how to do things, of how to perform physical tasks (often difficult to explain in words; easier to demonstrate)

1. e.g., tying shoes, working an algebraic equation, performing surgery

Types of Memory

THE NATURE OF MEMORY

•EXPLICIT MEMORY used when you consciously and deliberately try to remember something

•e.g., answering test questions, game shows, conversation

•IMPLICIT MEMORY the unintentional recognition and influence of prior experiences

•e.g., sports skills, reading, eating

Explicit and Implicit Memory

THE NATURE OF MEMORY

There are currently five models that attempt to explain memory.

1.INFORMATION PROCESSING MODEL

2.LEVELS-OF-PROCESSING MODEL

3.TRANSFER-APPROPRIATE PROCESSING MODEL

4.PARALLEL DISTRIBUTED PROCESSING MODELS

5.MULTIPLE MEMORY SYSTEMS

Models of Memory

THE NATURE OF MEMORY

INFORMATION PROCESSING MODEL

there are three stages of mental processing required before information can be firmly embedded in memory

1. SENSORY MEMORY

2. SHORT-TERM MEMORY

3. LONG-TERM MEMORY

Models of Memory

THE NATURE OF MEMORY

LEVELS-OF-PROCESSING MODEL

states that WHAT and HOW well we remember are a function of how deeply information is processed or encoded when first experienced

MAINTENANCE REHEARSAL repeating and item over and over

ELABORATIVE REHEARSAL building associations or linkages between new and old information; requires deeper level processing and results in stronger memories

Models of Memory

THE NATURE OF MEMORY

TRANSFER-APPROPRIATE PROCESSING MODEL

suggests the most important memory determinant is how well the processes involved during RETRIEVAL match the way the information was originally encoded

Models of Memory

THE NATURE OF MEMORY

PARALLEL DISTRIBUTED PROCESSING MODELS

suggests new facts are integrated with existing knowledge or memories

changes our overall knowledge base and alters our understanding of the world and how it operates

each unit of knowledge connected to every other unit of knowledge

allows us to quickly and efficiently draw inferences and generalizations about new and old info

Models of Memory

THE NATURE OF MEMORY

MULTIPLE MEMORY SYSTEMS

suggests the brain contains several separate memory systems

each system resides in a different area of the brain

each area serves different purposes

Models of Memory

STORING NEW MEMORIES

• SENSORY MEMORY holds information from all the senses.

• This information is held in SENSORY REGISTERS for a fraction of a second--just long enough for it to be processed further, if desired.

• Sensory memory allows us to experience a constant flow of information.

• SELECTIVE ATTENTION focuses mental processing on only part of the stimulus field, controlling what information is processed further.

• e.g., (of sensory information) __________________________________________________

__________________________________________________

Sensory Memory

STORING NEW MEMORIES

• SHORT-TERM MEMORY (STM) stores limited amounts of information for a limited amount of time (around 18 seconds unless rehearsed according to the Brown-Peterson procedure).

• STM is a component or WORKING MEMORY--that part of our memory which allows us to work with or manipulate the information in the STM.

• Working memory has at least two components:

1.MAINTENANCE (holding information in STM)

• MANIPULATION (working on that information)

• e.g., (of using working memory)__________________________________________________

Short-Term Memory and Working Memory

STORING NEW MEMORIES

• Encoding in Short-Term Memory

• Acoustic encoding (by sound) is the dominant form.

• Visual codes tend to decay faster than acoustic codes.

• Evidence exists to suggest there is also kinesthetic encoding (encoding by physical movement)

• e.g., (of each type of encoding) __________________________________________________

__________________________________________________

__________________________________________________

Short-Term Memory and Working Memory

STORING NEW MEMORIES

• Storage Capacity of Short-Term Memory

• IMMEDIATE MEMORY SPAN is the number of imtes you can recall perfectly after one presentation of a stimulus. This “magic number” is usually seven +/- two (five to nine) items or groupings of information.

• Groupings of information are called CHUNKS.

• STM can be noticeably improved by chunking--creating bigger and bigger chunks, or groups, of information.

• e.g., (of “practical” chunking) __________________________________________________

__________________________________________________

__________________________________________________

Short-Term Memory and Working Memory

STORING NEW MEMORIES

• Long-Term Memory (LTM) has the encoding and storage capabilities to produce memories that last a lifetime.

• ENCODING

• Some information is encoded in LTM without conscious effort.

• Most encoding is the result of elaborate, conscious processing and usually involves semantic encoding (which can result in problems if recall of specifics is important).

• Visual codes are also used to encode long-term memories. Dual coding theory states information is remembered better if both semantic and visual codes are used.

• e.g., (of both types of encoding)______________________________________________________

Long-Term Memory

STORING NEW MEMORIES

• Long-Term Memory (LTM) has the encoding and storage capabilities to produce memories that last a lifetime.

• STORAGE CAPACITY OF LTM

• Most theorists believe there’s no limit to the amount of info that can be stored in long-term memory.

• Most theorists also realize our memories can be quite distorted.

• Distortion can even occur in flashbulb memories--vivid recollections of personally significant events.

• e.g., (of flashbulb memories) ____________________________________________________

Long-Term Memory

STORING NEW MEMORIES

• IS THERE A DIFFERENCE BETWEEN SHORT-TERM AND LONG-TERM MEMORY?

• Psychologists disagree about the differences between STM and LTM.

• Some believe they are the same; that what is referred to as short-term memory is part of long-term memory that is being used at a particular moment in time.

• Other psychologists claim STM and LTM obey different laws.

• EXPERIMENTS ON RECALL

• Serial position curves show a tendency to recall both the first and last parts of a list--primacy and recency effects, respectively--when memory is immediately tested.

• It has been proposed that primacy effects reflect LTM and recency effects are due to STM.

Distinguishing Between STM and LTM

RETRIEVING MEMORIES• Retrieval is the ability to bring a memory into consciousness.

• RETRIEVAL CUES AND ENCODING SPECIFICITY

• RETRIEVAL CUES--stimuli that help people retrieve information from LTM.

• According to the encoding specificity principle, these cues are more efficient when they are related to the meaning of the originally encoded information.

• e.g., (of efficient retrieval cues) _______________________________________________________________________________________________________________________________________________________________

RETRIEVING MEMORIES• CONTEXT AND STATE DEPENDENCE

• CONTEXT DEPENDENT MEMORY--when memory is helped or hindered by an environment that is the same or similar to the one where the material was originally learned

• e.g., (of context dependent memory) _______________________________

• STATE DEPENDENT MEMORY--when a person’s internal state can aid or hamper retrieval

• e.g., (of state dependent memory) _________________________________

• In the mood congruency effect, recall is facilitated if a person’s emotional state is similar in tone to the information being recalled. People tend to remember more positive events when they are in a positive mood.

• e.g., (of mood congruency effect) __________________________________

RETRIEVING MEMORIES• RETRIEVAL FROM SEMANTIC MEMORY

• Semantic network theory

• suggests semantic memories represented in a dense network of association

• info retrieved through a spreading activation process (e.g., Thinking about concept X spreads neural activity to all other features, attributes,and concepts associated with concept X.)

• stronger association more quickly retrieved

• result of this network organization--we both retrieve facts we have learned AND also make conclusions about other facts

• e.g., (of spreading activation)__________________________________________________________________________________________________________________

RETRIEVING MEMORIES• RETRIEVAL FROM SEMANTIC MEMORY

• Retrieving Incomplete Knowledge

• when we retrieve some features and attributes of a concept but cannot access the entire concept

• Tip-of-the-tongue phenomenon when people cannot recall a particular word but can recall many features of it--its first letter, number of syllables, etc.

• Feeling-of-knowing experience when people cannot recall an answer but can retrieve enough info to determine whether the answer is actually stored in their memory and able to be correctly recognized

RETRIEVING MEMORIES• CONSTRUCTING MEMORIES

• People construct memories by using their existing knowledge to organize new information and to fill in gaps in information that is being encoded or retrieved.

• Relating Semantic and Episodic Memories (Parallel Distributed Processing Models): PDP models offer one explanation for how semantic and episodic info become integrated in constructive memories because they represent knowledge as LINKS in a network of associations.

• PDP networks can produce spontaneous generalizations, unsubstantiated assumptions that are based on limited or biased information.

• SCHEMAS are representations of categories of objects, events, and people.

• According to PDP models, the generalized knowledge contained in schemas provides the basis for making inferences about incoming information during the encoding stage.

RETRIEVING MEMORIES

• Factors influencing eyewitnesses’ ability to recall information during courtroom testimony

1) They can only remember what they perceive and perceive only what they pay attention to.

2) The semantic encoding typical of LTM can cause the loss of certain important details.

3) New info in questions AND how questions are asked can alter a witness’s memory.

4) Objects or events not witnessed but mentioned after the fact many be incorporated into memories (“misinformation effect”) and can occur for a number of reasons:

• New info may make it harder to retrieve the original memory.

• New info may be integrated into the original memory making it impossible to distinguish the new info from the original memory.

• If a respected person says an object was there or an event occurred, witnesses might believe this must be true.

Linkages: Memory, Perception, and Eyewitness Testimony

RETRIEVING MEMORIES

• Jurors tend to judge a witness as believable based on how the witness presents evidence, not just on what the witness says.

1) Jurors are more likely to believe witnesses who give very detailed accounts, even if those accounts are inaccurate.

2) Jurors are more likely to believe witnesses who are very confident, but research suggests that, on average, more confident witnesses are not more accurate. (Inflated confidence may stem from repeated exposure and recall of misinformation.)

• Eyewitness ID of criminals is more accurate when mug shots are viewed one at a time OR when witnesses are told the alleged perpetrator might not be included in the lineup.

Linkages: Memory, Perception, and Eyewitness Testimony

part 2

FORGETTING• HOW DO WE FORGET?

• METHOD OF SAVING Hermann Ebbinghaus’s method which involves computing the difference between the number of trials needed to learn something and the number of trials needed to relearn it again after some time has passed.

• This difference is called savings.

• Savings decline and forgetting increases as time passes.

• The most dramatic drop in what is retained in LTM occurs during the first nine hours, especially the first two.

• The shape of the forgetting curve (depicting how much and when people forget) stays relatively constant regardless of the type of info learned. After the intial strong drop in memory, the decrease moderates over time.

• Savings in LTM can be very long-lasting, retained often for decades.

FORGETTING• WHY DO WE FORGET?

• DECAY the gradual disappearance of the mental representation of a stimulus. Decay is prominent in forgetting in STM.

• INTERFERENCE a process through which the stoage or retrieval of information is impaired by the presence of other information.

• It may occur because one piece of information displaces other info or because one piece of info makes storing or recalling other info more difficult.

• It occurs in both STM and LTM but is more directly tied to forgetting in LTM.

• Retroactive interference learning new info interferes w/ recalling old info

• Proactive interference older info interferes w/ learning or recalling new info

• Some suggest all forgetting from LTM is due to some form of retrieval failure (interference) rather than decay. However, no one knows for sure why we forget.

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BIOLOGICAL BASES OF MEMORY

• Brain cells change as memories are formed and stored.

• One early theory (Donald Hebb, 1949) suggested that each memory is represented by a group of interconnected neurons called a cell assembly. This is the basis for the expanded, modern understanding of the biochemistry of memory.

• The formation and storage of new memories are associated with changes in synapses:

• When new synapses are formed, communication at existing synapses is altered. Repeated signals across a synapse increase the number of spines on the receiving dendrite, which appears to enhance memory capabilities.

• long-term potentiation synapses become “sensitized” to be more responsive to future stimulation (due to increased frequency of use)

• long-term depression synaptic connections become weakened (lack of use)

• The neurotransmitters glutamate and acetylcholine play important roles in memory.

The Biochemistry of Memory

BIOLOGICAL BASES OF MEMORY

• Memory involves both specialized regions for various types of memory formation and widespread areas for storage.

• The hippocampus, nearby parts of the cortex, and the thalamus are important in the formation of new memories.

• Other aspects of memory (such as sights and sounds associated with certain events) are stored if different parts of the cerebral cortex.

A little more info on memory and brain structures...

The hippocampus deals with directions and the long term memory . The amygdala incorporates memories and emotions. The cerebral cortex (also known as the outer layer of the brain) stores the long term memory in many brain regions depending on the information types, namely the language, sensory input, problem solving, decision making, etc.

Brain Structures and Memory

BIOLOGICAL BASES OF MEMORY

• The Impact of Brain Damage

• anterograde amnesia

• damage to hippocampus; loss of memory of events occurring AFTER the injury; cannot transfer new info from STM to LTM; cannot form explicit memories; implicit, procedural, and working memory remain intact; THUS...hippocampus appears to be crucial in the formation of episodic memories while other types of memories are controlled by other brain areas

• retrograde amnesia

• loss of memory of events that occurred BEFORE the injury; many patients regain most memories; may never remember last few seconds before injury; short-term memories never transferred to LTM; cases involving amnesia for hours or minutes before the trauma suggest that as memories move from STM to LTM, they are initially unstable and vulnerable to disruption; may take minutes, hours, or days before these transitioning memories are fully solidified, or consolidated

Brain Structures and Memory (cont.)

BIOLOGICAL BASES OF MEMORY

• Multiple Storage Areas

• Memories are likely stored in/around the cortex. Certain areas store specific aspects of a remembered event, but many brain regions are involved in experiencing the whole event.

• Memory problems observed due to damage to various brain areas are consistent with the view that STM and LTM are distinct systems.

• Research on memory retrieval:

• Imaging studies show the hippocampus and regions of the parietal cortex and prefrontal cortex are active during memory retrieval.

• Retrieving memories of certain experiences may also activate sensory and motor regions of the brain that may have been involved during the event itself.

• Research suggests that when memories are recalled, they may have to be stored again or reconsolidated. During this process the memory may be open to distortion.

Brain Structures and Memory (cont. again)

APPLICATIONS OF MEMORY RESEARCH

• The best strategies for improving memory are based on the elaboration of incoming information and linking new information to what is already known.

• Mnemonics strategies for placing info into an organized context to remember it

• Acronyms involve putting just the first letters of each of a list of things to be remembered into one easily recalled word or phrase.

• e.g., ____________________________________________________

• Verbal organization is the basis for many mnemonic devices such as stories or rhymes.

• e.g., ____________________________________________________

• The method of loci associates well-known locations with info to be remembered.

• e.g., ____________________________________________________

Improving Your Memory

APPLICATIONS OF MEMORY RESEARCH

• Guidelines for More Effective Studying

• Create a context, such as an outline, for organizing info.

• Use elaborate rehearsal with new info.

• Use distributed practice rather than massed practice.

• Practice retrieval of learned info by repeated self-testing (e.g., flashcards)

• Reading a Textbook

• Successful students monitor their understanding of their reading, reread difficult sections, and review periodically.

• Check for understanding before going on.

• To increase depth of info processing, use the PQ4R method (preview, question, read, reflect, recite, review)

• Lecture Notes

• Focus on expressing major ideas in relatively few words, draw connections with other material, and summarize main pts.

• Review notes ASAP after lecture to fill in missing details and create flashcards for key terms.

• When studying for an exam, create a detailed outline of notes and think about how various points are related.

Improving Your Memory

APPLICATIONS OF MEMORY RESEARCH

• The scientific study of memory has influenced the design of electronic and mechanical devices that play important roles in our lives.

• Common examples include:

• placing the least-likely-to-be-remembered instructions on a device

• using words for toll-free numbers to help people chunk information

• Other examples: ____________________________________________________________________________________________________________________________________________________________________________________________________________

Design for Memory