Duration of STM
Peterson and Peterson
- P's asked to count back in 3's to stop them from rehursing.
- Intervals for counting back in 3's varied.
- P's asked to stop counting and recall back the trigram.
-Results showed: longer the P's had to remember the trigram the less likely they were to remember.
Strength - High in internal validity
Weaknesses - cannot be generalised. Low ecological validity. - Capacity of their memory could effect their duration.
Duration of LTM
Bahrick et al (1975)
-Tested 392 graduates - Using two types of tests:
-Recall - P's shows pictures and asked to name them.
-Recognition - P's shown pictures and given a list of names.
P's performed well up to 34 years, performance declined after 47 years.
Strengths - High in external validity.
Weaknesses - Low in internal validity (may still have contact e.c.t.)
Encoding in STM
Showed P's a list of 6 consonants, each was shown for less than a second.
P's then wrote down what they had seen.
Conrad found that most mistakes were accoustic confusions (letters that sounded simiar B/B)
Encoding in LTM
Found a similar thing to Cin==onrad (STM encoding) but he found that when encoding info into the LTM the meaning of the words get confused.
WMM Adv + Disadv
KF Shallice & Warrington (1970)
Motor Cycle incident, left him with normal functioning LTM, but problems with STM. He forgot words and sounds more than visual stimuli.
Elsinger & Damasio (1985)
Case study of a man with brain damage - good reasoning skills and a high IQ. But desition making skills were very poor.