PSYCHOLOGY - Memory

Coding, Capacity and duration on memory.

What is the capacity of sensory memory?

Very large- Easy sensory store(Iconic, echoic, etc.) can take in lots of info. Sperling(1960) showed high capacity using a grid of letters and tone cues.

What is the duration of sensory memory?

Very short - Iconic store lasts about 0.5s, echoic store up to 2-3s.

Info fades quickly unless attention is paid.

How is information coded in sensory memory?

Coded in its raw, unprocessed sensory input. Each type of sensory memory stores details specific to the sensory modality, such as visual(Iconic) or auditory(echoic) features.

What is the capacity of short-term memory(STM)

The capacity of short-term memory is generally considered to be about 7 plus or minus 2 items(Miller,1956). Can be extended by chunking information into meaningful units.

What is the duration of STM?

About 18-30 seconds without rehearsal.

Peterson & Peterson (1959) used trigrams to demonstrate rapid forgetting.

How is the information coded in STM?

Mainly acoustically.

Baddeley(1966) found confusion with acoustically similar words in STM tasks.

What is the capacity of long-term memory (LTM)

Potentially unlimited.

What is the duration of LTM?

Can last a lifetime.

Bahrick et al (1975) showed people remembered high school classmates up to 48 years later.

How is information coded in LTM?

Mainly semantically, but can also be visual or acoustic depending on the memory type. Baddeley (1966) found confusion with semantically similar words.