memory Flashcards
sensory register
the memory store for each of our five senses
coding: modality specific: iconic/echoic
capacity: very large
duration: less than 1/2 a second
STM
coding: acoustic
capacity: 7 +-2
duration: 18-30 seconds
LTM
coding: semantic
capacity: unlimited
duration: up to a liftetime
retrieval
recovering information from storage
multi-store model
a theory of how the memory works in terms of 3 stores; sensory register, STM and LTM. also describes how information is transferred from one store to another, what makes some memories last and what makes some memories disappear
episodic memory
- specifically linked to personal experiences
— TIME STAMPED (you remember when as well as what)
— CONTEXT in which it happened as well as EMOTIONS you felt at the time
— you have to make a CONSCIOUS EFFORT to recall them
semantic memory
- consist of our shared knowledge of the world
- eg the capital of france is paris, or it is not appropriate to laugh when someone’s crying
- they usually start as episodic memories but gradually become semantic (eg last tuesday i learnt trigonometry…but as time goes on you forget when you did)
- the info can be generalised
episodic and semantic memories are declarative memories, similarities and differences?
similarities - explicit - we put in conscious effort to remember them
differences - E is time stamped, S is not…E are more vulnerable to distortion and forgetting, S less vulnerable
procedural memory
skill based info that becomes automatic after repetition
- linked to skill based info eg riding a bike
- becomes automatic after practice/repetition
- we are then less aware/conscious of these memories because they have become automatic
- these automatic skills allow us to multitask (not having to think about cycling allows us to focus on road safety)
anterograde amnesia
inability to make new memories from after the injury/illness
type of memory study:
Clive Wearing
global amnesia (anterograde and retrograde amnesia)
- caught a virus that attacked his CNS and hippocampus.
- duration of his STM = 7-30 seconds
- still has semantic and procedural memory, but not episodic as that is found in the hippocampus
shows: different types of memory exist, and damage to one doesn’t mean damage to others
retrograde amnesia
loss of memories from before the event
inference (Tulving)
a conclusion drawn about an unobservable behaviour based on other observable behaviours. memories are unobservable so cognitive psychologists must infer about their existence
- Tulving et al’s work gives a physical and objective reality to the different types of LTM: this is good
working memory model is about / made of
an explanation of how STM is organised and how it works
(Baddeley and Hitch (1974))
- WMM is concerned with the part of the mind that is active when we are temporarily storing and manipulating information from the environment
- 4 main components: central executive, visuo-spatial sketch pad, phonological loop, episodic buffer
central executive + capacity
- decides which data we should pay attention to
- allocates tasks to relevant slave systems
PROCESSING CAPACITY - very limited
phonological loop + capacity
- one of the slave systems
- processes auditory info (coding acoustic) and preserves the order in which the info arrives
- 2 subsystems
— phonological store - stores words you hear
— articulatory control system - allows for maintenance rehearsal, (repeating the words you hear in a ‘loop’ to keep them in working memory while they are needed)
CAPACITY - 2 seconds of what you can say
visuo-spatial sketchpad + capacity
- stores visual and/or spatial information
- Logie 1995 subdivided the visuo-spatial sketchpad:
— the visual cache - stores visual data
— the inner scribe - records the arrangement of objects in the visual field - CAPACITY limited to about 3-4 objects (Baddeley 2003)
episodic buffer + capacity
- the storage component of the central executive
- temporary store for info, integrating all info processes by the other stores and maintaining a sense of time sequencing ie recording events (episodes) that are happening
- limited capacity of approx 4 chunks (Baddeley 2012)
- links WM to LTM and wider cognitive processes like perception
forgetting: interference
- in LTM (permanent store, so forgetting must be because we cannot access the memories)
- interference occurs when a piece of information CONFLICTS with another piece of information. when this happens one memory blocks another one and the info is forgotten (info is distorted)
failure to retrieve is due to accessibility. interference stops us locating them in our LTM.
proactive interference
cant learn a new task due to old task interfering
(can’t remember new things, but remember old things)
retroactive interference
forgetting a previous learnt task due to learning a new task.
(remember new things not old)
real world interference study
Baddeley and Hitch 1977
they asked rugby players to recall names of the teams they played against over the same time (one season)
some players missed matches due to injuries though
players who played the most games (most interference for memory) had the poorest recall.
- study shows interference can operate in some real world situations, increasing validity of the theory
- counterpoint: interference may cause some forgetting in everyday situations but is unusual as conditions necessary for this to occur are rare unlike lab studies where ideal conditions for interference are created.
retrieval failure + cues
form of forgetting that occurs when we don’t have the necessary cues to access memory. available but not accessible unless a suitable cue is provided
cue = a trigger of information that allows us to access a memory
if context and feelings of individual are similar in recall and the situation where memory was originally processed, chances of recalling memory is higher
when info is placed in our memory, associated cues are also stored. internal (mood) and external (temp or smell) cues can help facilitate recall of an LTM
Encoding Specificity Principle (ESP)
Tulving 1983 reviewed findings into retrieval failure and found a pattern
“if a cue helps us recall info, it has to be present at encoding and at retrieval. “
some cues are meaningful (STM for short term memory) and some are not (context-dependent forgetting and state-dependent forgetting
context dependent forgetting
Godden and Baddeley 1975
deep sea divers learnt a list of words in 4 conditions
- learn and recall on land
- learn and recall underwater
- learn on land recall underwater
- learn underwater recall on land
bottom 2 conditions had 40% lower recall as external cues available at learning were different from the ones at recall, which led to retrieval failure
state dependent forgetting
Carter and Cassaday 1998
gave antihistamine drugs to Ps. had a mild sedative effect making them slightly drowsy. creates internal physiological state different from normal state of being awake and alert. Ps learnt list of words and passages of prose then recalled.
- learn and recall on drug
- learn and recall not on drug
- learn on drug recall not
- learn not on drug recall on
in mismatched conditions recall was significantly worse
eyewitness testimony is
a legal term, an account given by people of an event they have witnessed
how does eyewitness testimony work
witness encodes info into LTM, may be partial as the event occurs quickly/at night/accompanied by rapid of violent action.
witness retains info for a time, memories may be lost/modified during retention, other activities may interfere with the memory itself
factors affecting eyewitness testimony
misleading info:
leading questions - suggesting a desired answer
post-event discussion - witness discussion after an event that may influence accuracy of each witnesses recollection
eyewitness testimony: post event discussion case study
Gabbert et al (2003)
aim: to see if PED effects accuracy of EWT
procedure: Ps watched video of a girl stealing money from a wallet. Ps tested either individually (control group) or in pairs (co-witness group). this group were told they’d watched the same video, but really had seen different perspectives of the same crime, only one had witnessed the girl stealing. Ps discussed in the co-witness group, and then all of them did a questionnaire.
findings: found 71% of witnesses in co-witness group recalled info they hadn’t seen and 60% said girl was guilty even though they hadn’t seen her commit a crime.
evaluation: - questionable ecological validity, Ps knew they were in an experiment so more likely to have paid close attention to the details, results don’t reflect everyday examples of crime where witnesses may be exposed to less info.
+ good population validity - she tested uni students and older adults and found little difference between the conditions.
anxiety def
a state of apprehension worry or fear
- heart rate increases
anxiety negatively affects accuracy of EWT study
Johnson and Scott (1976)
the high-anxiety condition: overheard a heated argument in the neighbouring room, with the sound of smashing glass and a man walking through the waiting room with a bloody paper-knife
low anxiety: overheard a discussion in a lab about equipment failure, man walked out with a greasy pen
when asked to identify the man:
FINDINGS: participants in high-anxiety condition experienced 16% lower rates of accurate recall, compared to the low- anxiety condition.
this may be explained by the tunnel theory of memory and the weapon focus effect, where our attention is drawn towards the weapon as a source of anxiety.
strength: lab study - high control over EVs
limitation: participant variables (matched pairs design would be better)
anxiety positively affects accuracy of EWT
Yuille and Cutshall (1986)
they followed up 13 eyewitnesses, 5 months after a real-life shooting at a shop in Canada.
FINDINGS - eyewitness accuracy was still high after this period, with an 11% higher accuracy of recall for those eyewitnesses who ranked their anxiety as ‘high’ (compared to ‘low’) at the time of the shooting, using a 7-point anxiety scale
strength: high ecological validity (real life experience)
limitation: lack of control over EVs (natural experiment), participant variables
Yerkes-Dodson Law (anxiety)
suggests an ‘inverted-U’ relationship between increasing arousal and increasing performance (in this case the accuracy of EWT) with moderate arousal yielding the highest levels of performance
strength:
limitation: can be considered as overly-simplified explanation of anxiety, does not take into account the multiple factors which make up arousal eg cognitive, behavioural, emotional etc
cognitive interview def
a method of interviewing eyewitnesses to help them retrieve more accurate memories.
report everything, reinstate context, reverse the order, change perspective
