# Working Memory Working Memory is the cognitive system responsible for temporarily holding and manipulating information needed for complex tasks like reasoning, comprehension, and learning. Distinguished from passive short-term storage, working memory actively processes information. [[George Miller]]'s 1956 paper established its limited capacity (7±2 items), while Alan Baddeley's influential model (1974) proposed multiple components working together. Working memory capacity is one of the best predictors of general intelligence and academic success. The concept bridges [[Cognitive Psychology]], neuroscience, and practical applications. Working memory limitations affect everything from learning new skills to following instructions to problem-solving. When overwhelmed (cognitive overload), performance degrades. Understanding these limits is crucial for instructional design, UX design, and [[Personal Knowledge Management (PKM)]]. The prefrontal cortex plays a central role, and working memory declines with age but can be partially trained. ## Baddeley's Working Memory Model ``` ┌─────────────────────────────────────────────────────────────┐ │ CENTRAL EXECUTIVE │ │ (Attention control, coordination) │ │ │ │ │ ┌──────────────┼──────────────┐ │ │ │ │ │ │ │ ▼ ▼ ▼ │ │ ┌──────────────┐ ┌───────────┐ ┌───────────────┐ │ │ │ PHONOLOGICAL │ │ EPISODIC │ │ VISUOSPATIAL │ │ │ │ LOOP │ │ BUFFER │ │ SKETCHPAD │ │ │ │ │ │ │ │ │ │ │ │ Verbal info │ │ Integrated│ │ Visual/spatial│ │ │ │ Inner voice │ │ episodes │ │ Inner eye │ │ │ │ ~2 seconds │ │ │ │ │ │ │ └──────────────┘ └───────────┘ └───────────────┘ │ │ │ │ LONG-TERM MEMORY │ └─────────────────────────────────────────────────────────────┘ ``` ## Components | Component | Function | Capacity | |-----------|----------|----------| | **Central Executive** | Attention control, task switching | Limited | | **Phonological Loop** | Verbal/acoustic information | ~2 seconds | | **Visuospatial Sketchpad** | Visual and spatial information | ~4 objects | | **Episodic Buffer** | Integration across domains | ~4 chunks | ## Capacity Limits | Finding | Details | |---------|---------| | **Miller's 7±2** | Chunks that can be held simultaneously | | **Cowan's 4** | Core capacity without rehearsal | | **Duration** | ~15-30 seconds without rehearsal | | **Chunking** | Grouping increases effective capacity | | **Rehearsal** | Maintenance through repetition | ## Working Memory vs Long-Term Memory | Aspect | Working Memory | Long-Term Memory | |--------|----------------|------------------| | **Capacity** | Very limited (4-7 items) | Virtually unlimited | | **Duration** | Seconds to minutes | Days to lifetime | | **Encoding** | Automatic | Requires effort | | **Retrieval** | Immediate | Requires search | | **Forgetting** | Decay, displacement | Interference | ## Cognitive Load Theory ``` Types of Cognitive Load: ┌─────────────────────────────────────────────────────────────┐ │ INTRINSIC LOAD: Inherent complexity of material │ │ (Can't reduce—it's the content itself) │ │ │ │ EXTRANEOUS LOAD: Poor instruction design │ │ (Should minimize—confusing layouts, irrelevant info) │ │ │ │ GERMANE LOAD: Effort for schema construction │ │ (Should optimize—building understanding) │ │ │ │ Total must not exceed working memory capacity! │ └─────────────────────────────────────────────────────────────┘ ``` ## Applications | Domain | Implication | |--------|-------------| | **Education** | Chunk information, reduce extraneous load | | **UX Design** | Limit options, progressive disclosure | | **Instructions** | Step-by-step, not all at once | | **Presentations** | Less text, more visuals | | **Note-taking** | Offload to external memory | ## Design Guidelines (Miller's Law) | Guideline | Application | |-----------|-------------| | **Chunk information** | Phone numbers: 555-123-4567 | | **Limit menu items** | ~5-7 options per level | | **Use progressive disclosure** | Show only what's needed | | **Provide external memory** | Checklists, notes | | **Reduce split attention** | Integrate related info | ## Key Figures | Person | Contribution | |--------|--------------| | [[George Miller]] | Magical number 7±2 (1956) | | Alan Baddeley | Multi-component model (1974) | | Graham Hitch | Co-developed Baddeley model | | Nelson Cowan | 4-item core capacity | | John Sweller | Cognitive load theory | ## References - Miller, G.A. (1956). "The Magical Number Seven, Plus or Minus Two" - Baddeley, A.D. & Hitch, G. (1974). "Working Memory" - https://en.wikipedia.org/wiki/Working_memory ## Related - [[Memory]] - [[George Miller]] - [[Cognitive Psychology]] - [[Cognitive Science]] - [[Cognitive Load]] - [[Chunking]] - [[Attention]]