Short-Term & Long-Term Memory

Short-Term & Long-Term Memory

SHORT-TERM MEMORY

Capacity

> Jacobs - digit span 9.3 for digits and 7.3 for letters

> Miller - people remember about 7 items or chunks

Capacity Evaluation

> Cowan - 4 chunks is probably the limit, same for visual information (Vogan et al)

> Simon - larger chunks means fewer recalled

> Jacobs - 19 year olds have longer digit span than 8 year olds

Duration

> Peterson and Peterson - used consonant syllables, prevented verbal rehearsal, lasted 18 seconds

Duration Evaluation

> Consonant syllables not meaningful but some memory activities do involve such stimuli

> Reitman - auditory tones to avoid displacement, led to longer duration of STM

> Nairne et al - duration is 96 seconds

Coding

> Baddeley - difficulty remembering acoustically similar words but easy to remember semantically similar words

Coding Evaluation

> Brandimore et al - STM is visually coded if verbal rehearsal prevented

> Wickens et al - sometimes uses a semantic code

LONG-TERM MEMORY

Duration

> Bahrick et al - after 48 years, participants were 70% accurate in face recognition of classmates and 30% for names

Coding

> Baddeley - difficulty remembering semantically similar words, but easy to remember acoustically similar words

Coding Evaluation

> In Baddeley's study, LTM was tested by waiting 20 minutes, which isn't really LTM

> Frost - visual coding

> Nelson and Rothbart - acoustic coding