Visual STM Flashcards
Sperling (1960) showed that memories in the sensory register decay very rapidly i.e. within _ second. This was found using ___ & ___ report experiments
1, partial, whole
Name & describe 2 ways of testing STM capacity
The digit span test (how many digits can you repeat back to me?) = verbal STM. Corsi blocks test (how many tapped out locations can you tap back to me in order?) = spatial STM
Realise the relevance of several of these Q & As to MAIP, WM. Patient studies reveal a DD between verbal & visuospatial STM - explain & refer to the hemisphere in which the lesion resides
Patient KF (left parietal lesion): digit span of 2 but normal spatial span (& normal LTM). Patient ELD (RH lesion): impaired spatial span but normal digit span (& normal LTM)
The lesion data was supported by _ _ _ imaging data
PET
Baddeley & Hitch categorised the 3 levels of their WM model into 1), 2) & 3) from top (CE) to middle (phonological loop, episodic buffer & V-S sketchpad) to bottom (LT storage memory)
1) Top-down cognitive/executive control, 2) Fluid slave systems & 3) Cystallized systems
Owen (1999) conducted the same study as Blumenfield (2006) in your WM summary except that…(2 things)
1) PET was used instead of fMRI & 2) spatial span (maintenance only = recall locations in the correct order) vs. spatial N-back (manipulation too = recall the location N trials back) tasks were used
There is evidence to suggest that the VS sketchpad could be further fractionated into…
visuospatial & visual memory
What is the slot model of visual WM? How is it supported by Luck & Vogel’s (1997) data?
The slot model argues that visual WM has a fixed capacity of 3-4 slots of info. Successful performance in a change detection task (same or different?) when 3-4 items were displayed which then quickly diminished with 5+ items
The problem with Luck & Vogel’s argument that if info doesn’t get into a slot, it is not encoded at all and must be guessed about at test is that the change detection task…
cannot really tell us about the precision or quality of memories
Vogel (2001) argues that visual WM has a capacity of 3-4 fully bounded objects. TSB the finding that…
in the change detection task performance is very sensitive to the no. of objects (i.e. decreases with an increasing set size) but not to the type/ no. of features comprising each object e.g. whether an object is distinguished by its colour vs. orientation vs. a conjunction of features
In Bays & Husain’s (2008) study Pps were shown a display, followed by a target stimulus & were asked whether the target had…. As the no. of items in the display increased,…
Moved left or right or had been oriented clockwise or anticlockwise from when presented in the display. The precision of WMs decreased
In Bays & Hussain (2008) how was the precision of the memory calculated? How did this depict the finding?
By plotting a graph of displacement (in location) or rotation (of orientation) in degrees against the % of trials in which the target was judged to have moved or oriented e.g. clockwise. By showing a shallower curve as N (no. of items) increased = a courser, less refined WM
On the error graphs of Bays & Hussain’s (2008) study the finding is depicted by…
greater dispersion of the % of errors across degrees of displacement/ orientation rather than a focus at 0 degrees (as occurs when N is 1) where the task is most difficult
How do Bays & Husain’s (2008) refute the slot model?
By finding that the precision of WMs is degraded even when 2 rather than 1 pieces of info must be encoded.
WM precision is defined as 1/_ . When plotted logarithmically WM precision is found to be 1/
SD, N
Gorgoraptis (2011) found that the resource model (the idea that…) also applied to when items are presented sequentially rather than simultaneously - how?
we distribute our neural resources to however many items need to be remembered. By asking Pps to adjust an onscreen bar to the orientation of the bar (with this colour) which was previously presented. WM precision decreased (less & less) as N increased. The r/ship was linear after being log transformed
What does CDA stand for? What does it mean?
CDA = contralateral delay activity. The difference in activity between the hemisphere which is ipsilateral vs. contralateral to the VF of stimulus presentation
What has been found re: the CDA & VSTM? (Vogel, 2004)
The amplitude of the CDA over parietal cortex increases with the no. of items in the contralateral VF to be remembered…up to 4 items
Which model does the evidence on the CDA & VSTM supports? Why?
The slot model because the amplitude of the CDA plateaus at 4 items to be remembered in the contralateral VF
Todd (2004) found using fMRI that parietal cortex activity reaches its peak when _ items must be remembered. This supports the slot model
4
Some people argue that there is no difference between attention & WM. TSB at the neural level:
Frontoparietal networks (communication between parietal association cortex & PFC) are involved in both VS attention & VSTM in the macaque brain
Macaques with frontal lesions have impaired STM, as measured using the…
delayed match to sample task (remember where the peanut is placed)
Traditionally memory processing has been split into 3 phases:…. These stages can be dissociated using the CDR paradigm, which stands for…
1) encoding, 2) maintenance & 3) retrieval. Cue (memorise the location of the cue that lights up), Delay, Response (make a saccade to the remembered location)
According to Funahashi’s (1999) SURs from the macaque PFC the same cells are active during…in WM. These cells shows tuning to…
encoding, maintenance & retrieval. Specific spatial locations
Brozoski (1979) found that depletion of ___ (e.g. DA & serotonin) from the PFC leads to as severe deficits in macaque performance on the delayed match to sample task as removal of PFC
catecholamines
Catecholamines can be depleted using a _ _ ___ ___. This prevents PFC neurons firing in their usual, spatially specific manner and so impairs macaque performance on the…
D1 dopamine antagonist. Spatial memory saccade task
A macaque, D2 R antagonist (haloperidol)-induced deficit in spatial memory saccade task performance can be reversed by injecting systematically (globally) a _ _ ___ ___
D1 dopamine agonist
WM, LTM & speed of processing ___ with age, whereas world & verbal knowledge are ___ across age
decline, preserved
Evidence that WM declines with age comes from SURs in macaques (Wang, 2011). What is this evidence?
The degree to which single cells fire more in the preferred direction relative to the nonpreferred direction during the delay of the spatial memory saccade task fades with age
_ _ ___ can improve spatial memory in elderly monkeys (Castner, 2004)
D1 R agonists
WM improves with development (4 to 15 years of age) which is likely the result of… (Gathercole, 2004)
Maturation of the frontoparietal networks
WM capacity is highly associated with intelligence both at the ___ & ___ levels e.g….
Behavioural & neural levels (they activate similar brain areas) e.g. fluid IQ tasks activate frontoparietal networks (the “multiple demands system”)
WM can be improved but whether this transfers to improvements in __ __ is controversial. Jaeggi (2008) found it could.
Fluid IQ
Jaeggi (2008) used a WM task in which Pps were required to press a button whenever they…
Heard the currently presented letter or saw the currently presented location N trials back. Task difficulty is dynamically manipulated
Is PFC delay activity about WM maintenance (storage) or about…?
Ensuring attention is not sidetracked
