Memory

Memory

1. Capacity

   • Sensory Memory
     • Very high
   • LTM
     • Unlimited
   • STM
     • 18 -30 seconds
       • Millers Magic Number - 7-/+2
         • Miller may have overestimated the chunks. Cowan believes it is more likely to be 4 chunks
     • Joseph Jacobs - 7.3 for digits and 9.3 for letters
       • Conducted a long time ago and there could be extraneous variables effecting the validity of the results found.

2. Duration

   • SM
     • Less than half a second
   • STM
     • 15-30 seconds
       • Peterson and Peterson used Trigrams to test this, known as the Brown Peterson Technique.
         • It used artificial stimulus meaning the study lacked ecological validity
   • LTM
     • Lasts a lifetime
       • Bahrick did a study using students that had graduated from High School. The study tested their memory on whether or not they could remember those in their photo albums.
         • High ecological validity making the overall study more valid.

3. Encoding

   • SM
     • Iconic and Echoic
   • STM
     • Acoustic
       • Baddely carried out a study using 4 different groups
       • However, Brandimort realised that STM could be encoded visually also
   • LTM
     • Semantic
       • Baddeley carried out a study using 4 groups
       • On the other hand, Frost discovered that LTM could code visually also.
         • Nelson also discovered that LTM could code acoustically as well as visually and semantically

4. Multi Store Model- Atkinson & Shifirn

   • 3 stages in memory: Sensory Memory, STM, LTM and 2 control processes which are attention and rehearsal
     • Maintenance rehearsal is the repeating of the information currently in the SM, to be transferred to STM and then later transferred to LTM
   • The mutli store model is supported by those such as Baddely, Frost, Miller, Bahrick, etc
   • Brain Scanning images also provide evidence for the MSM as it shows different regions of the brain becoming active when STM and LTM are at work
     • However, there is more than just one type of rehearsal for information to be passed onto LTM. This is elaborative rehearsal. Also information does not always need to be rehearsed to be passed onto LTM
   • There is evidence that the LTM is split up into different components.