Key Studies PSYA 1

Serial positioning Curve

Aim: To see if they could find evidence for the existence of seperate STM and LTM

Glanzer + Cunitz 1966

Method:

1. Participents given a list of words to remember.
2. Some had to recall the words straight away
3. Others had to wait 30's untill they could recall the words

Results: The first and last words were easiest to remember. The middle words had been displaced

Limitation: Other researchers interpreted these results differently

KF's Case Study

Shallice + Warrington 1970's

Aim: To apply KF to the Working Memory Model

Info:

• In the 1970's KF was in a motorcycle accident, resulting in brain damage to his left occupational lobe.

Results: STM was damaged but LTM wasn't. He remembered words better is presented visually.

Strength: Supports Working Memory Model

Evidence supporting Visuo-Spatial Sketchpad

Baddley + Hitch 1974

Aim: Finding evidence to support Visuo-Spatial Sketchpad

Method:

1. Participents were given a visual tracking task where they had to trace the letter 'F' and describe all of the angles on this letter
2. In a second task participents had to complete a visual and a verbal task

Results: Participents found the second task easier than the first. This is because the sketchpad became overlooked/overloaded

Strength: Demonstartes/suppports the Visuo-Spatial Sketchpad

Weakness: Low ecological validity

EVR Case Study

Eslinger + Damasio

Aim: To studt the EVR Case

Method:

• EVR had a cerebral brain tumour removed.
• He perforomed well with problem solving tasks
• This suggests there are some problems with different aspects of his central executive but the WMM doesnt explain this

Results: EVR performed well when solving problems but took hours trying to make a decision

Limitation: Cannot establish causality

Capacity of STM

 Miller 1956

Aim: To investigate the capacity of Short Term Memory

Method:

• A review of other studies that scientists did and came up with the same results

Results: We chunk information. The span of immediate memory (STM) is 7+-2

Strength:

• Data was reasearched
• As you get older you can remember more in your STM

Duration of STM

Peterson + Peterson 1959

Aim: To find out the duration of Short Term Memory

Method:

1. Trigrams (3 letters) were given to participents
2. They were then asked to count backwards in 3's from 30
3. They were stopped at random points and told to recall their Trigram

Results: After approx. 18 seconds most people forgot their trigrams

Limitations:

• Low ecological validity
• Psychologists only testing one type of memory
• They could've been testing for displacement not duration

Duration of LTM

Bahrick et al 1975

Aim: To find out the duration of Long Term Memory, Recognition and Recall

Method:

• One group were shown pictures and had to name the people in them = Recall group
• Other group had to match the name to the picture and were given two lists of names = Recognition Group

Results:

• Recall = after 7 years 60%
• Recognition = after 14 years 90%

Limitiation: Some participents may still have been in contact with their peers

Encoding STM

Baddeley 1966

Aim: To investigate encoding in Short Term Memory

Method:

• Groups of people were given a short time to remember words

Results: Acoustic words (Sound the same) were harder to recall

Limitations:

• Does not test for other types of memory

Strengths:

• This test has been used for the post code system

Car Crash

Loftus + Palmer 1974

Aim: To investigate how misleading information can effect Eye Witness Testimony.

Method:

• 45 students were shown 7 films of traffic accidents
• There was 1 critical question
• The  groups had the words; hit,smashed, collided, bumped and contacted

Results:

Verb                     Speed Estimate

Smashed               40.8

Collided                39.3

Bumped                38.1

Hit                        34.0

Contacted              31.8

Limitation: Low ecological validity as it was a lab study, Increase in emotion, all students

Real Life Shooting

Yuille + Cutshall 1986

Aim: To investiagate how misleading information affects Eye Witness Testimony

Method:

• Witness a shooting
• Interviewed by Police
• 4-5 months later asked more questions
• 2 misleading questions (A broken headlight vs the broken headlight) and (The yellow 1/4 panel vs a yellow 1/4 panel)

Results: Misleading informatio had little effect. 10/13 said there was no broken headlight or 1/4 panel or they hadnt even noticed the details

Strength:

• High level of ecological validity
• Researchers took great care with counting details from the real incident

Limitation:

• Could've been a flash bulb memory

The role of anxiety in eyewitness testimony

Loftus 1979

Aim: To find out if anxiety during an witnessed event affects the accuracy of identification

Method:

1. A group of people overheard a low-key discussion in a lab about an equpiment failure. A person emerges with a pen and greased hands
2. Another group overheard a heated and hostile exchange between people in the lab. Sounds of glass and chairs braking were heard. A man emerged holding a bloody paper knife
3. They were shown 50 photos to see who the person was

Results:

1. Those who saw the pen man correctly identified 49% of the time
2. Those who saw the knife man accurately identifies 39% of the time

Limitation:

• Low ecological validity
• Ethical issues

EWT memory of elderly and young adults

Yarmey et al 1984

Aim: To investigate how age effects EWT

Method:

• Participents of varying age acted as mock witnesses
• They were shown a crime event which the individual carried a knife

Results:

• 80% of the elderly and 20% of the younger participents failed to mention the knife
• 75% of the elderly said the girl was a boy

Limitations:

• Lacks ecological validity
• Lacks internal validity

Effects of age on EWT

Valentine + Coxon 1997

Aim: To investigate how age effects EWT

Method:

• 3 groups of participents (Kids, young adults, elderly) watched a video of a kidnapping
• They were asked a series of leading questions about what they had seen

Results:

• The elderly and young gave the most incorrect answers to non-leading questions
• They were also most mis-lead by leading questions

Limitations:

• Lack of ecological validity
• Lack of internal validity

Cognitive Interview

Geisleman et al 1988

Aim: To test the effectiveness of the Cognitive Interview

Method:

• 89 students shown a video of a violent crime + interviewd 48hrs later by police
• They either had a standered interview or a CI

Results:

                            Cognitive        Standard

Correct items            41.5               29.4

Incorrect Items          7.3                6.1

Confabulated items    0.7                0.4

Limitations:

• Low ecological validity - small sample size (all students), artificial setting

Strength:

• High control - accurate analysis