retrieval induced forgertting plan

BENEFITS & COSTS OF HIGH WORKING MEMORY CAPACITY

BY JONATHAN MALL

Inhibiting irrelevant information

Structure

Why? Earlier work.Individual differences

InhibitionRetrieval induced forgettingRetrieval induced facilitation

IntroductionThe question whether verbal and spatial memory is independent from each other has previously resulted in conflicting findings. We aim to reconcile the evidence and together with our results shed doubt on the popular model of working memory (WM) featuring strictly independent stores. A domain-general store for both verbal and spatial information is suggested and individual differences are considered.

Earlier studies found little or no interference between concurrent visuo-spatial and verbal working memory tests but strong interference between simultaneous tasks involving only one domain [1-3], supporting a modular WM model [4]. However, a general capacity limit [5], an unpredicted strong effect of irrelevant speech [6] and the common use of unequaled tasks might have prevented clear interpretations.

We constructed tasks that were as equivalent as possible to test for cross-domain interference in order to fairly claim that interference between a verbal and spatial memory task reflects competition for a domain-general resource.

ConclusionWe found clear cross-domain interference between the verbal and spatial serial memory tasks, which contradicts a strict modular account of working memory. Concurrently holding verbal and spatial information in working memory negatively affected the recall of either, to a similar extent in each task.

MethodSimilar to Guérard & Tremblay’s [7] serial verbal and spatial reconstruction task, subjects had to report the correct order of spoken words or locations of visually presented squares. Words and locations were alternately shown, one at a time. They were either cued with the domain that would be tested (cued condition), saw a question mark (uncued) or received the correct cue but were only presented with one domain (single). The test screen always required order reconstruction of one domain. N=64 university students.

References[1] Cocchini, Logie, Della Sala, MacPherson & Baddeley (2002). [2] Farmer, Berman & Fletcher (1986). [3] Logie, Zucco & Baddeley (1990). [4] Baddeley (2007). [5] Saults & Cowan (2007). [6] Jones, Farrand, Stuart & Morris (1995). [7] Guérard & Tremblay (2008).

For more information or a copy of this poster, please contact J.T. Mall ([email protected]) or visit http://www.rug.nl/staff/c.c.morey/research

ResultsCross-domain dual retention significantly decreases memory performance. However, verbal memory exhibited a more pronounced recency effect which might be explained by supposing that the final item in a list is maintained in a short-term store, protected from subsequent interference. The reduction in performance in the uncued conditions, especially for the spatial task for which this decrement is present even at the shortest list length (3), suggests that verbal and spatial serial memory share some resource.

Individual Differences

High working memory capacity individuals seemed better able to ignore irrelevant information. Using single task performance as a measure of Working memory capacity, a median split resulted in two groups (high-WM & low-WM). Comparing their performance on Cued and Uncued trials we found a robust difference. High-WM individuals seem better able to use the cue to guide their behavior.

Cross-domain interference between verbal & spatial serial order working memory tasks

By Candice C. Morey & Jonathan T. MallThanks to my promoter Addie Johnson

time

Procedure

time

Results

Cross-domain dual retention significantly decreases memory performance. For verbal For spatial information

Individual differences

Domain specificity There could be separate working memory systems for

different modalities or types of representations (e.g. verbal vs. spatial)

An individual with verbal processing expertise should have fewer attentional resources available for the storage components involved in a spatial task & vice versa. But our data shows that performance covaries across domains

If you are good, you are good in both the verbal & spatial task

Definition

Working memory capacity: number of items that can be recalled during a

complex working memory task. Measured by: a memory span test that is embedded

within a secondary processing task

We use single task performance (STM) Sum of all correct items Median split of participants -> high & low wmc

Procedure

time


N=64

* *

Earlier studies

Dichotic listening procedure (Conway, Cowan, & Bunting, 2001)

AntBarTwo

MugCarTim

WMC difference

Ant.

Bar.

Two

Bottom-up attentional capture


Cocktail Party effect:Stroop: (Kane & Engle, 2003).

high WMC make fewer word-naming errors on incongruent trials when they were relatively rare

Congruent: Blue, Green, Red, Incongruent : Blue, Green, Red

It seems, that WMC modulates the active suppression or inhibition of “automatic” processes.

(Brewin & Beaton, 2002; Rosen & Engle, 1998)

New Study

Is the proposed inhibition effect the same as proposed for long term memory retrieval?

Subjects: Dutch students who completed a battery of Working Memory tasks (Operation Span, Symmetry Span & Raven)

Experiment: Retrieval induced forgetting

Retrieval induced forgetting

Learning: (all items)

10 categories + 6 exemplars

Study: (half the exemplars from half the categories)

Retrieve exemplar Retrieval Practice (RP)

Test: (all items)

Report all exemplars

LOUD – busLOUD – songLOUD –

SHARP – nailSHARP – knifeSHARP –

WEAPON – macheteWEAPON – glasWEAPON –

SHARP – n____SHARP – k____SHARP –

LOUD – b____LOUD – s____LOUD –

WEAPON – m____WEAPON – g_____WEAPON –

20

min

fille

r

Retrieval induced forgetting

Learning:

Study (retrieval): RP+ RP- NRP

Test:

LOUD – busLOUD – songLOUD –

SHARP – nailSHARP – knifeSHARP –

WEAPON – macheteWEAPON – glasWEAPON –

WEAPON – m____WEAPON – g_____WEAPON –

SHARP – n____SHARP – k____SHARP –

LOUD – b____LOUD – s____LOUD –

RP+

LOUD – streetLOUD – applauseLOUD –

RP-

WEAPON – macheteWEAPON – glasWEAPON – WEAPON – WEAPON – WEAPON –

NRP

20

min

fille

r

Stimuli

RP+RP- NRP

Category 6 – Exemplar 1Category 6 – Exemplar 2Category 6 – Exemplar 3Category 6 – Exemplar 4Category 6 – Exemplar 5Category 6 – Exemplar 6










20

min

fille

r

RIF

Hypothesis

If high WMC modulates inhibition during retrieval practice, a stronger RIF effect should be observed. However, many subjects required

Stimuli

RP+ RP- NRP

Shared feature






Category 1 – Exempla 1Category 1 – Exemplar 2Category 1 – Exemplar 3Category 1 – Exemplar 4Category 1 – Exemplar 5Category 1 – Exemplar 6





20

min

fille

r

Sharp - Weapon

Shared feature

Sharp Weapon

SCHERP - zaag WAPEN - krisSCHERP - vork WAPEN - baretSCHERP - spies WAPEN - glasSCHERP - floret WAPEN - hakmes

SCHERP - degenWAPEN - machete

SCHERP - ijspriem

WAPEN - werpster

RP+RP- NRP

Study (retrieval): longer RT due to bigger search-set More inhibition required to retrieve target item

Test: Bigger RIF effect Individual differences: RIF stronger for low WMC

Hypotheses

If high WMC modulates inhibition during retrieval practice, a stronger RIF effect should be observed.

If a larger search set requires more inhibition during retrieval, a stronger RIF effect should be observed for shared feature items. RT should increase with search set size Individual differences might exist (low WMC more

RIF)

Long term effect

Long term effects of testing. (Chan, 2010)

Facilitation of tested and non-tested items after longer delays

Options for delayed test

Only present the recall testRedo the taskRedo the task but switch RP+ & RP- items

Hypotheses

WMC modulates inhibition during retrieval practice leading to a stronger RIF effect.

A larger search set requires more inhibition during retrieval leading to a stronger RIF effect.

Former item inhibition facilitates relearning after a 24h+ retention interval.

Questions, suggestions, criticism…

retrieval induced forgertting plan

Education