Bahrick et al
Aim of this study: To investigate the retention of names and faces of high school classmates up to 47 years later using both recall and recognition
392 participants (ex pupils) of varying ages was tested. The participants had left school between 3 months and 47 years. Three measure of recall were:
- Free recall (trying to remember everyone in your class
- Name recognition (naming photos in year book
- Picture recognition (picking out the photos of your classmates)
- Free recall was worst than name recognition or face recognition at all times
- After 34 years, participants were around 90% accurate in picture recognition, 80% accurate in name recognition and around 50% correct in free recall
- After 47 years, participants were approx. 80% accurate in name recognition and picture recognition tests and 30% in free recall
This study used real life, meaningful material so it is likely that the results can be generalized to other types of meaninful long-term memories (high ecological validity)
One problem that would occur is controlling the number of times participants had met old classmates since they left school. People may have seen their classmates frequently
Bahrick tested recall of Spanish vocab and found that Spanish-English vocabulary recognition was as high at 70% 49 years after people had last studied Spanish.
Shepard showed 612 memorable pictures one at a time. One hour later they were shown these pictures mixed with pictures they hadnt seen with almost perfect recognition. 4 months later they were still able to recognise 50% of the photographs
The Multi-Store Model
Sensory Memory Store
- Info from the environment is reveived by sensory stores (eyes, ears nose etc)
- Type of encoding depends on the sense orfan used (eg visual encoding for the eyes)
- Duration- 50milliseconds
- If information is attended to it is processed further by STM
Peterson and Peterson- Memories in STM disappear after 18 secs when rehearsal is prevented. This supports the multi-store model because it proves if you don't rehearse memories will be lost
Areas of the brain-Milner and other cases studies of brain injury patients suggest that it is possible to damage STM but leave LTM intact and vice versa.
Brain scans can show us what part of the brain is active when doing certain tasks. Evidence has shown that when participants work on a task in STM the prefrontal cortex is active, whereas when LTM is in use the hippo campus is active. This supports the multi-store model because it shows separate stores in the memory and is located in different parts of the brain.
Hyde and Jenkinsdemonstrated incidental learning when participants were able to recall information later even though they had made no conscious effort to learn the material. The amount recalled depended on how the participants had processed information, not how long they rehearsed for.