Flashcards in Memory Deck (14):
Describe the 'cognitive neuropsychologist' approach to assessment .
What are some benefits to this approach?
This is a hypothesis-testing approach (Walsh, Kaplan), whereby every clinical case can be thought of as an 'experiment' by the clinical neuropsychologist.
Apply knowledge derived from cognitive neuropsychology (i.e., understanding of how cognitive processes work/break down) to determine the specific locus of a client's deficits.
Has the benefit of being able to specify issues, and allows for treatments to be targeted.
What is a 'memory'?
Binding is the core concept, a memory is effectively the binding of contiguous neural representations of 'what' 'when' 'where' and 'how' (i.e., the combination of these features make up the 'memory'.
In other words: an event/episode is defined by the conjunction of spatial and temporal features associated with an act (e.g., done by you, observed by you, told to you)
What neuroanatomical structures underly memory?
The hippocampus in particular is well-places and possesses the electrophysiological properties suited to capturing bound elements of 'an event' (producing a memory!).
However, other medial temporal lobe structures can also represent less complex event bindings. (e.g., entorhinal cortex as a 'gateway' structure)
How is the 'binding' of memory assessed?
Directly, through paired associates test (BINDING), or indirectly, through list-learning, prose learning, and coding!.
Paired associate learning tests are particularly sensitive to _______.
Medial Temporal Lobe Dysfunction / Temporal lobe amnesia (i.e., classic amnesia) ----- an encoding/consolidation problem.
Temporal lobe amnesia (i.e., classic amnesia) is broadly considered to be a _______ problem.
Does memory failure always imply a binding/Medial temporal lobe problem?
No. May reflect encoding/consolidation due to binding issue (mtl)
*poor initial encoding (reduced working memory, speed, strategy...)
* poor encoding/consolidation due to impoverished elements to be bound
* poor retrieval of a well-bound/consolidated trace (or of not well-bound/consolidated trace)
...all of the above
Describe Greg's idea of the 'perfect' cognitive neuropsychology process approach to testing memory.
1. Tests working memory - Single-trial learning with free recall of lists of 8 concrete words x3 (list A, B, C)
2. Item learning: free recall the SAME list of 8 concrete words - List C is repeated another two times. List D is done 3 times. [this is also preparation for PAL, all these words are well-remembered]
3. Paired associated learning - C-D pairing x3
can then consider performance on (2) list-learning, compared to (3) binding - using the same words.
1. List A (8 concrete words) free recall
2. List B (8 concrete words) free recall
3. List C (8 concrete words), List C, List C (learning!) free recall
4. List D, List D, List D free recall
5. List C-D bindings x 3 - cued recall each time
6. (30 minute delay)
7. C-D cued recall x1
8. Y/N recognition (foils were rematched pairings)
9. 2AFC recognition (with different rematched foils)
OR do CVLT-II than #3-9. and compare pattern
Define retroactive interference - what is the relevance of this to testing memory clinically?
Impact of subsequent learning on prior memory.
For example: RAVLT, WMS-III word list, CVLT-II --> all have interference list, following which there is typically a reduced ability to recall the initial list by around 2 items. Time delay has a similar effect, which could also be conceptualised as due to interference.
Retroactive interference is a prominent feature of medial temporal lobe dysfunction (and therefore MTL amnesia), as MTL performs binding operations that sub-index similar events -- when this is damaged, MTL is easily confused by interference! (which details should be bound together)
Responsible for the 'rapid forgetting' seen in Alzheimer's disease.
Define proactive interference - what is the relevance of this to testing memory clinically?
Impact of recently learned material on later learning. Can be thought of as the 'buffer being full'.
Not typically associated with forgetfulness, nor a prominent construct in clinical memory testing.
What are two important concepts in memory testing?
1. Susceptibility to interference (hallmark feature of TL memory disorder, classical amnesia syndrome AD, TLE, HSE, hypoxia)
2. Encoding vs. Retrieval
-encoding failure is also a feature of temporal lobe amnesia
- retrieval is typical with frontal/striatal or diffuse injury (TBI, MDD, PD(?), HD, FTD, DLB)
Describe how do differentiate between encoding and retrieval disorders of memory?
Compare free recall and recognition measures.
RECALL (a sensitive, but not specific tests) affected by both encoding and retrieval issues.
RECOGNITION (a specific test) - poor recognition reflects a failure to encode/consolidate a memory trace (the information can't be recalled even with help, because it is just not there!).
v [FROM LECTURE] v
* poor free (or cued) recall performance can be due to:
- Failure to encode/consolidate a memory trace
- Failure to retrieve a (more or less) adequately encoded trace
recall is a sensitive, but not specific test
* it establishes that there's a problem
* it doesn't tell us about the nature of the problem (e.g., it cannot distinguish between AD and depression)
* poor recognition performance is due to:
- failure to encode/consolidate a memory trace
- retrieval is not an issue!
Recognition is more specific (e.g., it will pick up cases of MTL encoding failure), but it is less sensitive as the high level of support means performance may be at ceiling, correct recognition may also be based on familiarity without recollection (51% sure is sure enough!)
Describe what an 'encoding' profile looks like on neuropsych testing:
Both recall and recognition are impaired
Recognition is not significantly better than recall
(i.e., it doesn't matter HOW you test for a memory trace, there just isn't one!)