The MSM

What is the MSM

A linear model that is made up of 3 unitary stores: sensory register, STM & LTM

Sensory register - coding, capacity, duration

• Coding: iconic (visual), echoic (sound), haptic (touch)

• Capacity: Large

• Duration: as short as ½ a second

How is information passed on and forgotten from the Sensory Register to the STM

• Passed on through attention

• Forgotten by decay

Short term memory - coding, capacity, duration

• Coding: Acoustically (changed into sound)

• Capacity: 7+ / -2

• Duration: 18-30s

How does information stay in, passed on and forgotten from the STM to the LTM

• Stays through maintenance rehearsal

• Passed in through prolonged rehearsal

• Forgotten by displacement decay

Long term memory - coding, capacity, duration

• Coding: semantically (according to meaning of information)

• Capacity: unlimited

• Duration: lifelong

How is information passed back to the STM and forgotten by the LTM

• Passed back through retrieval

• Forgotten by interference, decay, or retrieval failure

1st evaluation point for the MSM

• There’s research supporting separate stores of the MSM

• Murdock found the Primary-Regency effect - when participants were asked to recall a list of one syllable words they’d been asked to remember, they could only recall the words at the start and end, but not the middle

• Supporting the MSM as words at the start were rehearsed & in LTM, words at the end were fresh in STM. Words in the middle were displaced by new info, so aren’t recalled well

• Supporting distinction of STM and LTM, & role of rehearsal in passing on info from STM to LTM

2nd evaluation point for the MSM

• Fails to explain why we can transfer information to the LTM without prolonged rehearsal

• Craik & Lockhart - enduring memories are created by depth of processing, rather than always having to rehearse it. Processed information is more memorable as more effort goes into creating that memory

• Craik & Tulving - gave participants list of nouns & asked a question involving either shallow or deep processing. The participants remembered more words in the task involving deep processing than shallow

• This research contradicts original claim that prolonged rehearsal is required for info to pass onto the LTM, creating doubt over some assumptions of MSM

3rd evaluation point of MSM

• Evidence suggests STM and LTM shouldn’t be considered unitary stores

• Case study by Blakemore - virus damaged hippocampus of Clive Wearing, he had very little LTM for episodic memory, but still had his procedural memory as he could still play piano and reading music, suggesting the LTM isn’t unitary

• Case study by Shallice and Warrington - KF damaged his STM for information spoken to him, but could retain information presented visually, suggesting STM isn’t unitary

• Suggesting LTM may process episodic and procedural memory differently, and STM has separate visual and acoustic components, so MSM is unlikely to be an accurate model.