CH. 8: Memory Flashcards
Memory
Ability to store and retrieve information over time
Hermann Ebbinghaus
Did the early research on memory studying only one subject, himself, in the late 1800’s
Used nonsense syllables to remove meaning from memory
Best known for the forgetting curve and the spacing effect
There are three key functions of memory
Encoding: Process by which we transform what we perceive, think, or feel into an enduring memory
Storage: Process of maintaining information in memory over time
Retrieval: Process of bringing to mind information that has been previously encoded and stored
Memories are constructed
Memories are made by combining information we already have with new information coming in
There are three major ways to encode
Semantic encoding: Process of actively relating new information in a meaningful way to knowledge that is already in memory
Visual imagery encoding: Process of storing new information by converting it into mental pictures
Organizational encoding: Process of categorizing information according to the relationships among a series of items
Memory Storage
- Sensory memory - a few seconds retention
- Short-term memory - Non sensory - more than a few seconds but less than a minute
- Working Memory - processing
- Long-term memory -
Types of Sensory Memory
Sensory memory holds sensory information for a few seconds or less
- Iconic memory: Fast-decaying store of visual information
- Echoic memory: Fast-decaying store of auditory information
- Other senses memory: touch, taste, smell, and pain
Short-Term Storage and Working Memory
Short-term memory (STM) is storage that holds nonsensory information for more than a few seconds but less than a minute. It can hold about seven items.
- Rehearsal: Process of keeping information in STM by mentally repeating it
- Chunking: Combining small pieces of information into larger clusters/chunks that are more easily held in STM
- Working memory: STM storage that actively maintains information
Working Memory
The ability to temporarily hold and manipulate information for cognitive tasks performed in daily life
- Working memory holds information for a few seconds. It is temporary.
- Working memory can hold only five to seven items at a time. It has a small capacity.
- Working memory holds and manipulates information.
- Working memory depends on control of attention and mental effort.
The decline in short term memory
A 1959 experiment showed how quickly short-term memory fades without rehearsal.
On a test for memory of three-letter strings, research participants were highly accurate when tested a few seconds after exposure to each string, but if the test was delayed another 15 seconds, people barely recalled the strings at all (Peterson & Peterson, 1959).
The Flow of Information Through the Memory System
Model on Slide 11:
https://docs.google.com/presentation/d/1imdcmmoKmUdYY1xPyAa42c1g8upFgZ9y5lx9IoMbopQ/edit#slide=id.g3e212961db_0_226
Long-Term memory storage
- Long-term memory (LTM): Storage that holds information for hours, days, weeks, or years; no known capacity
- In contrast with both sensory and short-term memory, long-term memory has no known capacity limits.
- Hippocampus involvement (Filing cabinet?) Not the location of the memory in the brain
The hippocampus is critical as an “index” for long-term memory storage.
Case of HM who had his hippocampus (temporal lobe) removed to prevent seizures
- He could remember some things — scenes from his childhood, some facts about his parents, and historical events that occurred before his surgery — but he was unable to form new memories. If he met someone who then left the room, within minutes he had no recollection of the person or their meeting.
Anterograde amnesia
Inability to transfer new information from the short-term store into the long-term store
Retrograde amnesia
Inability to retrieve information that was acquired before a particular date, usually the date of an injury or operation
Consolidation
Process by which memories become stable in the brain
Reconsolidation
Memories can become vulnerable to disruption when they are recalled, requiring them to become consolidated again.
Memory Consolidation
Consolidation: Process by which memories become stable in the brain
Reconsolidation: Memories can become vulnerable to disruption when they are recalled or retrieved, requiring them to become consolidated again.
Interference: 1) Proactive and 2) Retroactive
Memory Malleability
Episodic Memory - Autobiographical Memory
Sleep on It!
Sleep plays an active role in memory consolidation (not just in the prevention of interference).
In an experiment, groups of people were given a picture-location task after sleeping or remaining awake.
- Both groups spent the same amount of time either sleeping or staying awake.
- The sleep group recalled more.
Sleep contributes to memory consolidation by increasing hippocampal involvement in recall a couple days later, and facilitating interaction of the hippocampus with the frontal lobe, such that the hippocampus is later less centrally involved in recall.
External context provides cues
Encoding specificity principle: Idea that a retrieval cue can serve as an effective reminder when it helps re-create the specific way in which information was initially encoded
Inner states also provide cues.
State-dependent retrieval: Tendency for information to be better recalled when the person is in the same state during encoding and retrieval
Matching encoding and retrieval contexts improves recall.
Transfer-appropriate processing: Memory is likely to transfer from one situation to another when the encoding and retrieval contexts of the situations match.
Context dependent memory
Retrieval of Memories
Information is sometimes available in memory, even when it is not accessible.
Retrieval cues: External information associated with stored information that helps bring that information to mind
Serial Position Effect
First position and last position most memorable
Information presented at beginning and at the end:
Primacy and Recency effects
Forms of Long-Term Memory
Explicit - Intentionally remembered
Implicit- Remembered but not by intention
Explicit Memory: Semantic and Episodic
Semantic memory: Network of associated facts and concepts that make up our general knowledge of the world
Episodic memory: Collection of past personal experiences that occurred at a particular time and place
Implicit Memory
When past events influence present events without an effort to remember, e.g., ride a bike, tie your shoes, swim etc
Procedural memory is a type of implicit memory, e.g., athletic skills
Priming - An enhanced ability to recall a word or stimulus as a result of a previous exposure to the stimulus though the previous exposure is not remembered by the person. Unconscious memory.
The illusion of truth- What is true?
Memory Failures
False memory - Recalling an event that did not happen
Misinformation effect - Details of an event that are added but did not occur (eyewitness)
Bias: Distorting influences of present knowledge, beliefs, and feelings on recollection of previous experiences
- Consistency bias: Tendency to reconstruct the past to fit the present
- Change bias: Tendency to exaggerate differences between what we feel or believe now and what we felt or believed in the past
- Hindsight bias: People overestimate their ability to predict an outcome
Cryptomnesia - a new thought that actually is a memory
–skajdhgljkd–
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Retroactive interference: Situations in which information learned later impairs
memory for information acquired earlier - Proactive interference: Situations in which information learned earlier impairs memory for information acquired later
- Transience - memory fades with time
Forgetting - It has a purpose!
–skjadhgfls–
Memory misattribution: Assigning a recollection or an idea to the wrong source (Frontal lobe involved) (source amnesia)
Suggestibility misattribution - incorporating misleading information from external sources into a memory
False recognition: Feeling of familiarity about something that hasn’t been encountered before (Deja vu)
- Same brain activation as true recognition (including hippocampus)
Cryptomnesia - Belief a thought is new when it is actually a memory
Peak-End Rule
Judge an event on how it felt at peak and how it ended - Judged by snapshots of prototypical moments, not the entirety of an experience.
