Participants were divided into four groups which were acoustically similar, acoustically dissimilar, semantically similar and semantically dissimilar. Participants were presented with the list a total of 4 times and each time was interrupted to try to prevent rehearsing. They were then presented with a 20-minute interval task and afterwards were asked to recall their list. Semantically dissimilar words were recalled the most telling us that encoding in LTM is semantic.
Summary of study on capacity of STM and LTM Summary of study on duration of STM Peterson & Peterson- Showed PPs a list of nonsense trigrams and asked them to count back from 400 in 3 second intervals for a duration ranging from 3 to 18 seconds. Found that duration of STM was 18-30 seconds maximum. Summary of study on duration of LTM Bahrick- 400 participants aged between 17 and 74 were tested using different methods including free-recall tests, photo-recognition test, name recognition tests and photo-name matching test. PPs performed less well on free recall tests (30% after 48 years) but were much better in the photo-name test (90% after 60 years).
Models of memory Description of the multi-store model of memory, plus evaluation inc. research Atkinson & Shiffrin- Multi-Store Model which consists of three parts – sensory, short term and long term stores. Rehearsal is required in order for information to move across stores and retrieval is needed to access the information. If information is not rehearsed it will decay.
Description of the working memory model, plus evaluation inc. research Baddeley & Hitch- Working Memory Model which consists of three parts – central executive, phonological loop (store and articulatory control system) and the central executive. Memory in the real world Knowledge of what Eye Witness Testimony (EWT) is- The evidence provided in court by a person who witnessed a crime, with a view to identifying the perpetrator of the crime. The accuracy of eyewitness recall may be affected during initial encoding, subsequent storage and eventual retrieval.
Loftus & Palmer’s (1974) study on EWT- Reconstruction of an Automobile Disaster. 9 student PPs per 5 conditions (bumped, contacted, hit, smashed and collided). All watched a video then asked to estimate speed. Smashed the highest (40.8mph) and contacted the lowest (31.8mph). PPs in second part of experiment then asked a leading question about broken glass. 16/50 of the smashed condition PPs said yes in comparison to 7/50 in the hit condition.
Knowledge of the factors which affect the accuracy of EWT anxiety- Christianson and Hubinette (1993) Anxiety and EWT – real incidents involving high levels of stress lead to more accurate, detailed and long lasting memories. Deffenbucher (2004) Carried out a meta-analysis of 18 studies, looking at the effects if heightened anxiety on accuracy of EWR. It was clear that there was considerable support for the hypothesis that high levels of stress negatively impacted on the accuracy of EWM.
Age- Parker and Carranza (1989) Compared the ability of primary school children and college students to correctly identify a target individual following a slide sequence of a mock crime. In the photo identification task, child witnesses has higher rate of choosing ‘somebody’ than adults witnesses, although they were also more likely to make errors of identification than college students.
Weapon focus effect- Loftus(1987) In violent crimes, arousal may focus attention on central details e.g. a weapon. Loftus et al identified weapons focus effect. 2 conditions, one involving weapon the other not. Condition 1 (less violent) people was 49% accurate in identifying man. Condition 2 (more violent) people were 33% accurate. Suggests weapon may have distracted them.
Brief details on other research on EWT Features of the cognitive interview plus evaluation Fisher et al developed a memory retrieval procedure for eyewitnesses, ‘the cognitive interview’ that consists of four general retrieval mnemonics: -Report everything- The interviewer encourages the reporting of every single detail of the event, even if it appears to be irrelevant. Mental reinstatement of original context- The interviewer encourages the interviewee to mentally recreate the environment and contacts from the original incident.
-Changing the order- The interviewer may try alternative ways through the timeline of the incident. -Changing the perspective- The interviewee is asked to recall the incident from multiple perspectives. Strategies for memory improvement Visual Mnemonic- A memory technique that uses visual images. For example, method of loci and mind maps. Verbal Mnemonics- A variety of memory improvement techniques that focus on words and their sounds. For example, acronyms and rhymes.
Learning theory Classical conditioning-learning through association, food produces pleasure Operant conditioning-leaning by consequences, food is a primary reinforce, feeder becomes secondary reinforce. There have been other studies proving/disproving the learning theory, you will need to know them. Shaffer and Emerson- Studied 60 babies every 4 weeks throughout 1st year of life, then again at 18 months. Assessed separation episodes. found babies were clearly attached to those who were not involved in physical care (disproving)
Dollard and Miller – found the mother came associated with the removal of unpleasant feelings of hunger, as a form of negative reinforcement (supports operant conditioning) Harlow- Used rhesus monkeys. Separated them from mothers at birth, raising them in isolation cages. Monkeys became distressed when ‘baby blanket’ was removed (attachment not based on association with food). Harlow provided a wire mother with food and a soft mother without food. Monkeys preferred soft mother; showing they had an innate, unlearned need for contact. (disproves learning theory)
Bowlby- evolutionary theory Bowlby believes: Attachment is a behaviour that has evolved because of its survival and reproductive value. Children have an innate drive to become attached to a caregiver because of long term benefits. (Similar to imprinting.) The caregiver will feed and protect the child and increase survival chances.
Sensitive period- Hodges and Tizard- longitudinal study, 65 children put in an institution less than 4 months old. 70% said they didn’t care deeply about anyone. Early privation has a negative effect on the ability to form attachment’s Universality-Tronik et al- studied an African tribe in Efe, they were from extended family. Infants were looked after and breast fed by different women but slept with their mother at night, after 6 months they still showed one PAF Monotropy – Shaffer and Emerson – also agreed that strongly attached infants had mothers who responded sensitively to their demands and offered them most attention, but weakly attached infants had mothers who didn’t interact with them.