Plasticity: the brains ability to change as result of experience
Plasticity is greatest during childhood
However, plasticity persists throughout life
It occurs by changing the pattern of connectivity between neurons
Short term memory: memory for information currently help in current consciousness
Capacity of STM
-this is also known as phonological memory it can be assessed using span tests
Miller in 1956 suggested that span is 7 +/- 2
He denotes that these as meaningful chunks of information
Capacity is not strictly related to meaningfulness of chunks because:
Span length is lower polysyllabic words (skeleton, binoculars, etc)
Span length is lower for phonologically similar words (map, cat, etc.) another thing that can influence span is the opportunity to rehearse the material span is reduced if participants are asked to silently mouth irrelevant speech while encoding a list
This is known as: Articulatory suppression silently mouthing words while performing some other task.
Developed by Baddeley
Baddeley found that recall of word lists from STM is reduced for longer words and affected by articulatory suppression
Span tasks involve two components: a phonological store and a rehearsal mechanism based on subvocal articulation that refreshes the memory store
ALSO KNOWN AS: the phonological loop
Articulatory suppression impairs the subvocal articulation that refreshes the memory store.
How do STM and LTM interact?
Atkinson and Shiffrin created the modal model of memory
According to the MODAL MODEL information can only get into LTM, and get out of it again, VIA the short term system
Model assumes that amount of time in STM predicts later learning
STM is characterized as mostly verbal info.
*** LOOK AT DIAGRAM IN BOOK
-this model divides memory into very short-lived sensory registers a general purpose short-term store and LTM
-HOWEVER, empirical memory does not support this model things don’t have to spend along time in STM for it to go to LT
How it actually works!
-STM is important for LTM
BUT, contemporary components suggests that there are various components and each component is material specific
Damage to a specific component will affect learning of that specific material rather than learning per se.
-it has been suggested that there is a STM capacity for visuospatial information this suggests a role in visuospatial STM in long term learning of visual information
Working memory: a system for the temporary storage and manipulation of information
An extension of short term memory because you can manipulate info as well
Emphasizes a wider role in cognition (reasoning, comprehension, etc.)
WHEREAS, short term is often taken to imply a passive retention of material
Thus, WM involves the retention and processing of info. In a limited capacity short-term store
The prefrontal cortex (PFC) is responsible for refreshing info in the stores (rehearsal) –and manipulating that info
E.g. using a list of #’s in STM to perform calculations
In general, a network of regions are involved with conjoint activation of both frontal regions (involved in manipulating and retrieving information) and posterior regions (involved in storing of material).
1. Model of WM (Atkinson & Shiffron)
Verbal memory vs. visuospatial memory
a. Parts of STM that are specialized for these distinctions (mentioned above in STM section)
The phonological loop and visuospatial sketchpad are known as Slave Systems
a. Central executive = TRANSFERS/TRANSFORMS information from either the loop or the sketchpad
Thus, the central executive coordinates the slave systems, and cognition in general, by retrieving things from memory, specifying task goals, and initiating and terminating cognitive routines
It is the interaction between the flexible executive system and the more specific processing routines that is the ESSENTIAL characteristic of a WM.
Now how long term memory…