MEMORY Flashcards
Coding Definition
The way that information is changed so it can be stored in memory
Coding - Baddeley’s Study
Baddeley (1966) - immediate recall worse with acoustically similar words, recall after 20 mins worse with semantically similar words
Evaluation:
Baddeley’s study didn’t use meaningful material
Capacity Definition
The measure of how much information can be held in memory
STM capacity = 7+/-2
LTM capacity = unlimited
Studies for Capacity
Jacobs (1887) - digit span: participants able to repeat back 9.3 numbers and 7.3 letters (short term 7+/-2)
Miller (1959) - span on STM is 7+/2 but can be improved with chunking
Evaluation
- Jacob’s study outdated
- Miller’s research may have overestimated STM
Duration Definition
How long information can be held in memory before it is no longer available
STM duration = 18-30 seconds
LTM duration = lifetime/unlimited
Studies on Duration
Peterson & Peterson (1975) - students recalled 80% of syllables correctly, average recall after 18secs fell to 3%
Bahrick et al (1975) - participants tested 48 years after graduation were 70% accurate in photo recognition
EVALUATION
- Peterson & Peterson’s study is artificial
+ Bahrick’s study high external validity
Chunking
Grouping letters or digits together to remember them more easily
E.g., remember a phone number in chunks
Long Term Memory
Memory store for info that has been stored for a long period of time
Coding: Semantic
Capacity: Unlimited
Duration: Lifetime
Short Term Memory
Limited capacity and duration memory store
Coding: Acoustic
Capacity: 7+/-2
Duration: 18-30 seconds
Sensory Register
The memory stores for each of the 5 senses
Multi-Store Model of Memory (MSMM)
Sensory store —attention—> STM —maintenance rehearsal—> LTM
• Attention needs to be paid to sensory info for it to move to STM
• Maintenance rehearsal for long enough moves it to LTM
• Retrieval - recall information to STM from LTM in order to remember it
The Working Memory Model (WMM)
Baddeley & Hitch
Central Executive - monitors incoming data and allocates slave systems to tasks
Visuo-Spatial Sketchpad - Sores visual and spatial information when required, divided into Visual Cache: stores visual data and Inner Scribe: records arrangement of objects in vision
Episodic Buffer: Temporary store for information, integrates visual, spatial, verbal info from other stores, maintains sense of time sequencing so records events happening
Phonological Loop - Deals with auditory info and preserves the order in which the info arrives, divided into Phonological Store: stores words heard, Articulatory Process: Allows maintenance rehearsal
Coding & Capacity of Central Executive in WMM
Coding: Flexible
Capacity: Very Limited
Coding & Capacity of Visuo-Spatial Sketchpad in WMM
Coding: Visuo and Spatial
Capacity: 3-4 objects
Coding & Capacity of Episodic Buffer in WMM
Coding: Flexible
Capacity: 4 ‘chunks’
Coding & Capacity of Phonological Loop in WMM
Coding: Acoustic
Capacity: 2 seconds of acoustic info
Evaluation of The Working Memory Model
+ Dual task performance studies support Visuo-spatial Sketchpad
+ Word length effect supports Phonological Loop
+ Support from brain scan studies
- Lacks clarity over central executive
Evaluation of MSMM
+ Supported by research into coding, capacity and duration
- Evidence suggests STM is not just one store
- Oversimplifies STM
- Research uses artificial tasks
What is the Visuo-Spatial Sketchpad divided into?
Visual Cache: stores visual data
Inner Scribe: records arrangement of objects in vision
What is the Phonological Loop divided into?
Phonological Store: stores words heard
Articulatory process: allows maintenance rehearsal
Types of LTM
Episodic - Events/Episodes from our life, time-stamped and have to make conscious effort to recall
E.g., First time driving a car
Semantic - Stores our knowledge of the world, less personal
E.g., What a car is and how it works
Procedural Memory - Stores memories for actions and skills, recall occurs without awareness or effort
E.g., How to drive a car
Evaluation of types of Long Term Memory
+ Support from case of HM - couldn’t make new semantic or episodic memories but visibly improved on procedural task
+ Brain scan studies show there’s different stores for LTM
+ Identifying diff LTM stores has real life applications
— Problems with clinical evidence, lack of control when dealing with people with brain damage
— Tulving has suggested there may only be 2 types
Forgetting: Proactive Interference
When an older memory distrusts a new one
Forgetting: Retroactive Interference
When a new memory disrupts an old one
McGeoch & McDonald (1931) + Evaluation
Interference stronger when memories are similar
Participants asked to learn list of words to 100% accuracy
Performance depended on nature of 2nd list of words
Most similar material (synonyms) caused worst recall
When participants were given very different material, such as 3-digit numbers, the mean number of items recalled increased
+ Evidence from lab studies
+ Real-life studies support
- Research studies includes artificial materials
- Interference effects may be overcome by using cues
Forgetting: Retrieval Failure
When information is initially placed in memory, associated cues stored at same time so if those cues aren’t available at time of recall, you may not be able to access memories that are there
State-Dependent Forgetting
When memory retrieval is dependent on an internal cue, state of mind
Context-Dependent Forgetting
When memory retrieval is dependent on an external/environmental cue
Evaluation of Retrieval Failure
+ Lots of evidence that supports explanation of forgetting
+ Context-related cues useful for everyday application
- Evidence to show that context effects are not very strong in real life
- Contextual effects only occur when memory is tested in certain ways
Eyewitness Testimony (EWT): Misleading Info; Leading Questions
Response-Bias Explanation: Wording of question has no enduring effect on EW memory of event but influences kind of answer given (EW answer influenced but memory isn’t)
Substitution Explanation: Wording of a question does affect EW memory, interferes with original memory, distorting the accuracy (EW memory and answer influenced)
Loftus and Palmer (974): EWT Leading Questions
5 groups of participants all given different verb in a critical question: hit, contacted, bumped, collided or smashed
Verb “contacted” produced a mean estimated speed of 31.8mph, the verb “smashed” produced mean of 40.5mph.
Leading question biased eyewitness recall of event
Eyewitness Testimony: Post-Event Discussion
When co-witnesses discuss a crime/event
Memory Contamination: When co-witnesses discuss a crime, the mix of info from the other witnesses contaminates real memories
Memory Conformity: Witnesses go along with each other to win social approval or because they believe the other witnesses are right
Eyewitness Testimony: Post-Event Discussion - Gabbert et al (2003)
Participants watched video of the same crime filmed from different angles
71% mistakingly recalled aspects that they did not see in the video but had picked up during post-event discussion
Evaluation of EWT: Misleading Information
+ Research has real-life applications
- Loftus & Palmer’s study used artificial materials
- Could be individual differences in accuracy of EWT
- Lab studies suffer from demand characteristics
- EWT studies lack external validity
Eyewitness Testimony: Anxiety had a Positive Effect
Yuille & Cutshall (1986) - Witnesses were very accurate and there was little change after 5 months
Eyewitness Testimony: Anxiety has a Negative Effect
Johnson & Scott (1976) - 49% of participants in low anxiety condition were able to identify the man in the lineup, high anxiety was 33%
Tunnel Theory of memory argues a witness’s attention is on the weapon (weapon focus) because it is a source of danger and anxiety
Evaluation of EWT: Anxiety
- Johnson & Scott’s study may test surprise not anxiety
- Field studies lack control variables
- Some ethical issues involved in researching anxiety
- Yerkes-Dodson Law is limited as it’s too simplistic
- Demand Characteristics may have arose in the studies
EWT: The Cognitive Interview
Report everything, change perspective, reinstate the context, reverse the order of events
Evaluation of Cognitive Interview
+ Research suggests that some elements are very useful
+ Support for the effectiveness of the enhanced Cognitive Interview
- Time Consuming
- Research may be unreliable because of variations of the cognitive interview
- Produced an increase in inaccurate information
