Encoding, Capacity and Duration

Encoding = The way information is changed so that it can be stored.

Example:  When you smell a blow off, you automatically think 'errrr, someone has done a blow off!'.  you have automatically recoded a smell into an acoustic code, allowing it to pass on to the short-term memory store!

Capacity = How much information can be stored

Duration = The length of time information can be stored

	Sensory Memory	Short Term Memory	Long Term Memory
Encoding	Information is stored in its raw form.  Information floods the senses and enters the sensory store associated with each individual sense: For example: Iconic – Visual Echoic – Sound Haptic - Touch	Baddeley (1966) * Mostly Acoustic (through sounds) Additional research also points to visual encoding	Baddeley (1966) * Mostly Semantic (through meaning) Additional research shows other encoding methods are used, depending on what is being attended to.  e.g. Visual encoding is used when storing faces
Capacity	Iconic is much larger than Echoic	Jacobs (1987) * Digit Span Technique 7 +/- 2 units of information ‘Chunking’ increases capacity	Unlimited – cues required for retrieval
Duration	Echoic – lasts up to 2 seconds Iconic – Lasts a mere 0.5 seconds	Peterson & Peterson (1959) 18 seconds, if rehearsal is prevented.	Bahrick (1975) * Year book study 90% recall of information from information stored over 48 years ago. A very long time – but cues are required to aid retrieval.

* Research can be found at:

http://www.simplypsychology.org/Short%20and%20Long%20Term%20Memory.pdf