Memory 1- Basic of Memory,, Short Term Memory (STM), and Working Memory PERTEMUAN 4

4.1 Introduction to memory Memory refers to our ability to: –retain information about past experiences –the processes by which we acquire, record or encode information –the processes by which we store information in an accessible format –The processes by which we can later retrieve that information.

Methods of testing memory Free recall (also called spontaneous recall) –you are required to generate the test items from your own memory without any outside help Cued recall –you are required to generate test items from your own memory, but with the aid of reminders or ‘retrieval cues’ which may help to jog your memory Recognition –In a recognition test the original test items are re- presented at the retrieval stage, and you are merely required to indicate whether or not you recognise them.

Multistore models of memory William James (1890) put forward theories about two types of memory store, which he called ‘primary memory’ and ‘secondary memory’. Now replaced by the terms ‘short-term memory’ and ‘long-term memory’ Short-term memory (STM) –memories which we are holding in conscious awareness, and which are currently receiving our attention Long-term memory (LTM) – memories which we are not presently holding in conscious awareness, butwhich are held in storage ready to be recalled.

4.2 Short-term memory Information from our senses enters short- term memory (STM) via sensory registers STM is a temporary store for relatively unprocessed (sound-based or visual) information. –Verbal STM has a limited capacity of 7 ± 2 items, which can be used most efficiently by chunking the information to be remembered.

Measuring STM performance Digit span test

Serial position curves for immediate and delayed recall

4.3 Working memory Working memory refers to the processes that temporarily store and manipulate information so that we can use that information to follow a conversation, solve problems etc. Baddeley and Hitch’s model of working memory comprises the phonological loop (PL), visuo-spatial sketchpad (VSSP), central executive and, recently, the episodic buffer

4.4 Forgetting and remembering

Two main mechanisms of forgetting, from STM or LTM, have been proposed. –Decay theory proposes that memory fades with time –Interference theory proposes that forgetting occurs because memories disrupt with each other.

4.5 Limits and failures of memory Case study: Temporal lobe surgery (HM)

4.6 Mental representation A representation is a sign, symbol or token that ‘re-presents’ something in its absence analogue representations –representations bear some physical resemblance to the object or event they represent. –For example, a painting or scale model of a town may retain the structural features and spatial layout of the buildings and streets in that town.

symbolic representations –do not resemble the represented object or scene in any way. –For example linguistic representations, letters and words are arbitrary symbols that bear no physical relation to the phonemes or items they represent. –they symbolize rather than mimic the thing they stand for

Imagery Mental imagery provides us with a way of experiencing novel situations or re-experiencing past events Baddeley (1986) assumed that visual imagery is a function of the visuo–spatial sketchpad (VSSP) of working memory. Logie, Zucco and Baddeley (1990): –visual imagery interferes more with visual short-term memory (STM) than with verbal STM –whereas mental arithmetic interferes more with verbal STM than visual STM.

Concepts A concept is a unit of knowledge that allows us to recognize novel stimuli as types of thing we have encountered before typicality effects

Connectionism Connectionist models exhibit parallel distributed processing (PDP).