memory - created from Mind Map

Página 1

msm

WMM

Explanations for Forgetting

EYE WITNESS TESTIMONY (EWT) & FACTORS AFFECTING ACCURACY

The Multi-Store Model (MSM) was proposed by Atkinson & Shiffrin (1968). It explains memory as three separate stores through which information passes in a linear process:

sensory register

Short-Term Memory (STM)

Long-Term Memory (LTM)

Sensory Register → Short-Term Memory (STM) → Long-Term Memory (LTM)

Key Processes in MSM

Process Description Attention Focus on sensory input → moves to STM Rehearsal Repeating information → maintains STM; elaborative rehearsal → transfers to LTM Retrieval Accessing information from LTM back to STM

Strengths of MSM

Limitations of MSM

Empirical support: Lab studies support separate stores (e.g., Peterson & Peterson; Baddeley). Simplicity: Provides clear stages and processes. Practical application: Helps understand memory disorders (e.g., amnesia).

Oversimplified: Assumes STM and LTM are single, uniform stores. Ignores other types of LTM: Episodic, semantic, procedural not distinguished. Evidence from case studies: HM and KF suggest STM is more complex (e.g., different stores for auditory vs. visual info). Rehearsal isn’t always necessary for LTM (e.g., flashbulb memories).

Function: Receives information from the environment via the senses. Duration: Very brief (<0.5–2 seconds depending on the sense) Capacity: Very large (all sensory input, but only a fraction is attended to) Coding: Modality-specific (e.g., visual = iconic, auditory = echoic) Key Study: Sperling (1960) – Partial report technique showed iconic memory holds large amounts briefly. Transfer to STM: Requires attention.

Function: Holds information currently being used or attended to. Duration: ~18–30 seconds (without rehearsal) Capacity: 7 ± 2 items (Miller, 1956) Coding: Mainly acoustic Maintenance: Rehearsal (repetition) is key for retention. Transfer to LTM: Requires elaborative rehearsal (linking information meaningfully) Displacement: New information can push out old info if capacity is exceeded. Evidence: Peterson & Peterson (1959) – duration of STM tested using trigram recall with varying intervals.

Function: Stores information indefinitely. Duration: Potentially lifelong Capacity: Essentially unlimited Coding: Mainly semantic (by meaning) Retrieval: Information moves back to STM via retrieval Supporting Evidence: Bahrick et al. (1975) – very long-term recall of high school classmates.

The Working Memory Model (WMM) was proposed by Baddeley & Hitch (1974) as a more detailed alternative to the STM component of the MSM. It suggests that STM is not a single store but a multi-component system for temporary storage and manipulation of information.

Components of the WMM

Strengths

Weaknesses

Key Features

Active system: Holds and manipulates information, not just stores it. Modality-specific: Different subsystems for different types of info (PL = verbal, VSS = visual). Limited capacity: Each subsystem can hold only so much information. Supports dual-task studies: Shows how different components can work independently.

Central Executive (CE)

Phonological Loop (PL)

Visuo-Spatial Sketchpad (VSS)

Episodic Buffer (EB) (added 2000 by Baddeley)

Directs attention and coordinates the other subsystems. Allocates mental resources depending on the task. Very limited capacity. Modality-free (can handle any type of information). Evidence: Dual-task studies (Baddeley & Hitch, 1976) – participants could do verbal and visual tasks simultaneously, showing separate components are managed by CE.

Processes verbal and auditory information. Limited to about 2 seconds of speech or ~7 items. Deals with language, sounds, and speech-based memory. Evidence: Word-length effect (Baddeley, 1975) – harder to remember long words than short words.

Stores visual and spatial information. Limited to about 3-4 objects at a time. Handles visual patterns, images, and spatial awareness. Evidence: Brooks (1968) – visual and verbal tasks interfere only when they share the same subsystem.

Integrates information from CE, PL, VSS, and long-term memory (LTM). Creates coherent “episodes” of memory. Limited capacity of around 4 chunks. Evidence: Explains how we can combine visual, verbal, and long-term memory info in one task.

Explains dual-task performance better than the Multi-Store Model. Supported by strong experimental evidence (PL, VSS studies). Accounts for manipulation of information, not just storage.

Central Executive is vague and hard to measure directly. Less clear on interactions with long-term memory. VSS may be more complex than a single subsystem.

Forgetting is the inability to recall or retrieve information that was previously stored. Psychologists explain forgetting using two main approaches: interference and retrieval failure.

Interference Theory

Retrieval Failure Theory (Cues)

Forgetting occurs because one memory blocks another, causing confusion. Works best for similar types of information.

Proactive Interference (PI)

Retroactive Interference (RI)

Evidence:

Evaluation:

Older memories interfere with new ones. Example: You keep typing your old password instead of your new one.

New memories interfere with older ones. Example: Learning a new phone number makes you forget your old one.

McGeoch & McDonald (1931): Participants learned a list of words, then a second list. Forgetting was greatest when the second list was similar to the first. Shows interference is strongest when memories overlap or are similar.

✅ Lab studies show consistent effects. ❌ Artificial tasks (lists of words) may not reflect real-life forgetting. ❌ Doesn’t explain forgetting of unique, meaningful memories.

Forgetting occurs when cues are absent. The memory is available but not accessible. Key idea: Memory retrieval depends on having the right cues present.

Context-dependent forgetting

State-dependent forgetting

Evaluation:

External environment acts as a cue. Example: Godden & Baddeley (1975) – Divers recalled words better in the same environment they learned them (land vs water).

Internal state (mood, drugs) acts as a cue. Example: Goodwin et al. (1969) – Participants who were drunk when learning remembered less if sober at recall

✅ Strong evidence from lab and field studies. ✅ Explains everyday forgetting well. ❌ Some studies have failed to replicate cue effects in real-life settings.

EWT is an account given by a person of an event they have witnessed. Memory for events can be highly accurate or distorted, making EWT an important topic in forensic psychology.

Memory is reconstructive – people often fill gaps with assumptions or expectations. Accuracy can be influenced by internal and external factors.

FACTORS AFFECTING EWT ACCURACY

Misleading Information

Anxiety / Stress

Cognitive Interview (CI)

Other Factors

Definition: Information presented after an event can distort a witness’s memory. Types: Leading questions – questions that suggest an answer. Study: Loftus & Palmer (1974) – Participants asked how fast cars were “smashed” vs “hit.” Higher speed estimates and false memory of broken glass for “smashed.” Post-event discussion – discussing events with others can alter memories. ⭐ Star Evaluation: ✅ Strong lab evidence for leading questions altering memory. ✅ Explains real-life courtroom errors. ❌ Lab studies use artificial tasks (videos vs real crime), limiting ecological validity. ⭐ Advanced: Memory conformity – witnesses may incorporate others’ memories into their own.

Definition: High arousal or stress at the time of a crime can affect recall accuracy. Effects: Negative effect: High stress can narrow attention, reducing memory for peripheral details. Study: Yuille & Cutshall (1986) – Real-life shooting; witnesses with highest stress recalled details more accurately – shows sometimes stress improves memory (flashbulb effect). Weapon focus effect: Presence of a weapon draws attention to it, reducing memory for other details. Study: Johnson & Scott (1976) – Witnesses focused on a bloody knife rather than the perpetrator’s face. ⭐ Star Evaluation: ✅ Supported by real-life and lab evidence. ✅ Shows stress is not always negative (inverted-U hypothesis). ❌ Ethical constraints make it hard to test extreme stress experimentally. ⭐ Advanced: Yerkes-Dodson law – moderate stress can improve memory; very high stress impairs it.

Definition: Technique to improve accuracy and quantity of EWT. Techniques: Report everything – even minor details. Reinstate context – mentally recreate the environment. Reverse order – recall events in different sequences. Change perspective – imagine the event from another viewpoint. Evidence: Geiselman et al. (1985): CI increased correct recall in lab settings compared to standard interviews. ⭐ Star Evaluation: ✅ Increases quantity and accuracy of recall. ✅ Supported in real-life police work. ❌ More time-consuming than standard police interviews. ⭐ Advanced: Enhanced Cognitive Interview (ECI) – includes social rapport and open-ended questions, further improving accuracy.

Age: Children and older adults may be more susceptible to suggestion. Time delay: Longer delays between event and recall increase forgetting and distortion. Individual differences: Intelligence, stress resilience, and eyewitness training affect memory accuracy.