Human Memory Overview

Study Notes

Memory is the process of retaining and recalling information over time.
Memory is composed of three interconnected processes:
- Encoding: Converting external stimuli into neural signals (structural, phonetic, or semantic processing).
- Storage: Maintaining encoded information over time (short-term or long-term memory).
- Retrieval: Recalling stored information for cognitive tasks. Memory problems can occur at any stage.

Information Processing Approach (Stage Model):
- Compares human memory to a computer system with three stages:
  - Sensory Memory:
    - Registers sensory information briefly and accurately (visual "iconic" or auditory "echoic").
    - Large capacity but very short duration (seconds).
    - Acts as a buffer to allow attention to filter relevant information.
  - Short-Term Memory (STM):
    - Holds limited information temporarily.
    - Duration is usually less than 30 seconds.
    - Encoded primarily acoustically.
    - Capacity is limited, typically 7+/-2 items.
    - Maintenance rehearsal (repetition) and chunking (grouping items) can help maintain information.
    - Information is transferred to long-term memory if it's rehearsed or meaningful.
  - Long-Term Memory (LTM):
    - Permanent storage with virtually unlimited capacity and duration.
    - Encoded semantically (meaning-based).
    - Examples include learned skills, events, and facts.

STM isn't a single system; it's a dynamic workspace with multiple components:
- Phonological Loop: Rehearses sound-based information briefly.
- Visuospatial Sketchpad: Stores and manipulates visual/spatial information.
- Central Executive: Controls and coordinates cognitive tasks, directing attention.

Memory retention is influenced by the depth of processing:
- Shallow Processing: Focuses on superficial features (e.g., font or color).
- Intermediate Processing: Focuses on phonetic features (e.g., sounds).
- Deep Processing: Focuses on meaning and relationships (results in better retention).

Declarative (Explicit) Memory: Consciously recalled information.
- Episodic Memory: Personal experiences (e.g., first day of school).
- Semantic Memory: General knowledge and facts (e.g., capitals, rules).
Procedural (Implicit) Memory: Unconsciously recalled procedures (e.g., playing an instrument).
Autobiographical Memory: Detailed memories of personal events.
Flashbulb Memory: Vivid and detailed memories of emotionally significant events.

Forgetting is the inability to retrieve previously stored information.
Theories include:
- Trace Decay: Memory traces fade over time.
- Interference: Information competes with other stored memories (proactive and retroactive interference).

Retrieval is the process of bringing stored information into awareness.
Forgetting may occur when retrieval cues are absent or ineffective.
Repressed memories (traumatic, distressing experiences suppressed) is one explanation.

Mnemonics: Strategies using imagery and organization to aid recall (including keyword and method of loci).
Chunking: Grouping related information into meaningful units.
PQRST Method: Preview, question, read, self-recite, and test.
Deep Processing: Connecting new information to existing knowledge.
Minimize Interference: Avoid overlapping study topics or learning events.
Retrieval Cues: Create effective cues to recall information.