Models of memory

Short term memory

Aka working memory, ability to hold a small amount of information for a short period, usually seconds to a minute

Long term memory

stores information for extended periods from hours to a lifetime

Multistore Model of Memory

Atkinson and Shiffrin/ suggested the MSMM, which describes memory as a flow of information through the 3 main stores: sensory memory, short-term memory. and long-term memory/ Each memory stores information differently, in the way it is processed (encoding), how much can be stored (capacity), and for how long (duration)

MSMM Sensory Memory

Sensory information from the environment enters sensory memory, related to different sense like hearing and vision/ stays ¼ to ½ seconds, only small amount is transferred to STM 

MSMM Short term memory

If we give attention to information, it is moved into short term memory/ seven items (7±2), 6-18 seconds, with rehearsal information may stay up to 30 seconds/ without rehearsal, information may be displaced from STM by new information

MSMM Long term memory

Believed to be of indefinite duration and maybe unlimited capacity/ information can be recalled from LTM into STM when needed

Types of rehearsal

Maintenance rehearsal: repetition of information to remember it/ Elaborative rehearsal": involves linking new information in a meaningful way with information already stored in long-term memory

Evidence supporting MSMM

Serial position effect: primacy and recency effect/ Primacy effect: we tend to remember the words in the beginning of the list because we had time to rehearse them, stored in LTM/ recency effect: we tend to remember words for the end of the list because they are stored in STM/ words in the middle of the list is asymptote

Glanzer and Cunitz

46 army enlisted men/ used repeated measures design/ shown 15 fifteen word lists on a screen where words were common one syllable words, shown for 1 second with a 2 second interval between words/ conditions were immediate recall where both primacy and recency effects were shown, the 10 second delay recall where recency was reduced and the 30 second daly recall where there was no trace of the recency effect/ this suggests that words from the beginning of the list had already been transferred to LTM through rehearsal, where the distractions displaced the words at the end of the list from STM

Strengthens of MSMM

There is significant research to support the theory of separate memory stores/ the model is of historical importance

Limitations of MSMM

Over simplified, assumes each of the stores works as an independent unit/ does not explain memory distortion/ does not explain why some things may be learned with minimal rehearsal/ does not explain why we can rehearse information and it is not transferred to LTM/ does not explain the potential role of emotion in memory

Data that doesn’t fit into MSMM

Phonological Similarity Effect, Word Length Effect/ Phonological Similarity Effect: Conrad et al, participants required to recall rhyming and non rhyming list, MSMM does not account for this/ Word Length Effect: capacity for STM is greater for shorter words than longer words where people tend to recall a larger number of words from a list with smaller syllables, MSMM does not account for this

Working Memory Model

Baddeley and Hitch/ suggest that STM is not just a single store, observed participants performing two tasks simultaneously, dual-task technique/ central executive, phonological loop, episodic buffer, visuo-spatial sketchpad, long term memory storage

WMM Central executive

most important part of the model/ decides how to allocate sensory information to different sub-systems/ attention control system that coordinates the operations of the sub-systems/ interacts with memories stored in LTM/ limited capacity/ modality free, process any sensory information whether auditory or visual 

WMM Phonological loop

Two components: articulatory control system (inner voice), turns visual stimuli into sounds/ phonological store (inner ear), holds sounds in a passive manner

WMM visuo-spatial sketchpad

the visual component of STM, inner eye/ temporary store for visual and spatial information from either sensory memory or LTM/ visual processing includes storing and manipulating visual patterns and spatial movements in two or three dimensions/ visuospatial sketchpad helps us remember what visual information is important and where it is

WMM Episodic buffer

Temporarily holds several sources of information and integrates it with information in LTM/ passive display store until information is need/ limited capacity

Study for WMM

Strengths of WMM

supported by considerable experimental evidence/ brain scans have shown that different brain areas are more active when performing verbal than visual tasks/ case studies of patients with brain damage support the theory that there is more than one STM store/ helps us understand why we can multi task in some situations and not others

Limitations of WMM

role of central executive is unclear even though it is known as the most important part of the model/ how various components of the model interact is still unclear/ only explains STM not LTM/ does not explain memory distortion or role of emotion in memory