Definition of Memory: Memory shapes individual identity and is crucial for daily decision-making and recollection of personal history.
Multi-Store Model of Memory: Proposed by Atkinson and Shiffrin (1968), outlines different stores for memory:
Sensory Memory
Short-Term Memory (STM)
Long-Term Memory (LTM)
Sensory Memory
The initial phase of memory where sensory information is stored temporarily.
Types of Sensory Memory:
Iconic Memory: Visual information, stored in less than 1 second.
Echoic Memory: Auditory information, stored for approximately 3 seconds.
Haptic Memory: Tactile information, details less explored in research.
Effective use of attention moves information from sensory memory into short-term memory.
Visual Memory Example
Sparklers: Example of iconic memory where a visual trail is left when moving a sparkler in darkness; a representation of how visual information is integrated.
Historical method by Johann Segner used spinning cartwheels with glowing coals to determine the duration of iconic memory (~100 milliseconds).
Short-Term Memory (STM)
Definition: Temporary storage of information, limited duration, and capacity.
Characteristics:
Limited Capacity: Miller's magic number (7 ± 2 items).
Duration: Information lasts approximately 15-30 seconds in STM without rehearsal.
Factors Influencing STM
Chunking: A strategy to enhance capacity by grouping information into larger units (e.g., phone numbers).
Digit Span Test: Used to measure digit and letter recall capacity (historically, about 9 digits and 7 letters).
Serial Recall vs. Free Recall
Serial Recall: Recall items in order they were presented; typically more difficult due to the recency effect, where the latest items are recalled better.
Free Recall: Items can be recalled in any order; generally easier than serial recall.
Primacy Effect: Items at the beginning of the list remembered better due to more rehearsal time.
Recency Effect: Items at the end of the list remembered better due to being still in STM.
Memory Recall Experiment
Conducted a distractor task (counting backwards) to observe its impact on recall.
Result: Demonstrated that distracting tasks significantly reduce recall ability.
Encoding and Its Effects on Memory Retrieval
Encoding: Process of transferring information into memory; crucial for recall.
Mistakes in recall can indicate encoding methods:
Phonological errors (e.g., misremembering "moose" as "goose") indicate encoding by sound (phonology).
Semantic errors (e.g., misremembering "moose" as "elk") suggest encoding by meaning (semantics).
Common errors tend to be phonological, indicating how sound influences recall more than meaning.
Conclusion
Memory processes critically shape individual experiences and identity.
In-depth exploration of memory will continue with working memory in the next lecture.
Emphasis on understanding encoding mechanisms for enhanced memory retention strategies in future discussions.