Is errorless learning a useful concept in the treatment of word retrieval disorders?

Lyndsey Nickels, Kate Makin, Belinda McDonaldMelanie Moses & Christine Taylor

Speech Pathology Service, Royal Rehabilitation Centre Sydney

& Macquarie Centre for Cognitive Science

Treatment of word retrieval disorders (anomia) in aphasia

• Word retrieval disorders can be successfully treated.

• But no single treatment is successful for every individual.

• Do not yet understand the circumstances under which treatments work (who, what, when, why and how)

• Our research aims to investigate these issues

Errorless learning

Hypothesis• Remediation is more effective if errors are prevented

- the act of producing an error may strengthen the incorrect association, and make the correct response less likely to occur.

• Technique widely & successfully used with people with acquired memory impairments (amnesia)

• E.g. Baddeley & Wilson, 1994

Errorless learning and anomia treatment

• Fillingham et al (2003)

“error reducing techniques do have positive effects for patients with word finding difficulties. As yet there is limited information on which to judge whether this technique is significantly advantageous over errorful approaches” (p358).

This study:

compares an errorful and errorless approach directly using facilitation

Facilitation?

• The effects of performing a task once on subsequent performance (usually of another task).

• Compare effects of two different tasks on word retrieval in individuals with impaired word retrieval

- Errorless / error reducing (repetition)

vs

- Errorful (phonemic cueing)

Tasks

“kangaroo”

Errorless

Repetition

“k”

Errorful

Phonemic cueing

Method

Name 300 pictures until 95 failed (10 second limit)

Sort the failed items into 3 (frequency & length)matched sets

Errorless Errorful Control

Facilitation

Name all 3 sets of pictures+ 30 easy fillers

1 week later

10 mins later

Participants

15 individuals with aphasia & word production impairments.

Age 31-74

9 women, 6 men.

11 Left CVA, 3 TBI, 1 HSE.

Time p.o. 6 months – 20years

8 fluent aphasia; 7 non-fluent

Majority show comprehension impairments

(word-picture matching)

All have impaired picture naming

-0.10

0.00

0.10

0.20

0.30

0.40

0.50

FM

E

JNI

KC

C

PS

J

DR

S

JUE

SJS

JMM

DIP

MC

B

WV

K

FA

B

JOW

MF

T

SM

G

Mea

n

Phon Cues

Repetition

Facilitation effect compared to control pictures:Errorless (Repetition) & Errorful (Phonemic cues)

*

*

*

*

*

**

*

-0.10

0.00

0.10

0.20

0.30

0.40

0.50

FM

E

JNI

KC

C

PS

J

DR

S

JUE

SJS

JMM

DIP

MC

B

WV

K

FA

B

JOW

MF

T

SM

G

Mea

n

Phon Cues

Repetition

Facilitation effect compared to control pictures:Errorless (Repetition) & Errorful (Phonemic cues)

*

*

*

*

*

**

*

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

FM

E

JNI

KC

C

PS

J

DR

S

JUE

SJS

JMM

DIP

MC

B

WV

K

FA

B

JOW

MF

T

SM

G

Mea

n

ben

efit

rep

etit

ion

- c

ue

Relative benefitErrorless (repetition) vs Errorful (phonemic cueing)

Ph

on

cue b

enefit

Rep

etition

ben

efit

*

*

**

-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

FM

E

JNI

KC

C

PS

J

DR

S

JUE

SJS

JMM

DIP

MC

B

WV

K

FA

B

JOW

MF

T

SM

G

Mea

n

ben

efit

rep

etit

ion

- c

ue

Relative benefitErrorless (repetition) vs Errorful (phonemic cueing)

Ph

on

cue b

enefit

Rep

etition

ben

efit

*

*

**

Summary

• Errorless (repetition) & Errorful (phonemic cueing) tasks significantly facilitate subsequent naming over 10 minutes later.

• Errorless (repetition) significantly more beneficial than errorful (phonemic cueing).

cf Best et al – no significant difference between repetition & cueing.

Conclusion: Errorless tasks are more beneficial than errorful tasks in the treatment of aphasia

Conclusion

Errorless tasks are more beneficial than errorful tasks in the treatment of aphasia

Why might we doubt this simple conclusion?

1) Can we be sure the errorless task was more accurate?

How errorless is errorless? Accuracy of the facilitation task.

Repetition is more errorless than cueing.

(except for JNI)

0.00

0.20

0.40

0.60

0.80

1.00

FME

JNI

KCCPSJ

DRSJU

ESJS JM

MDIP

MCB

WVK

FABJO

WM

FTSM

GM

ean

repetition

phoncue

Conclusion

Errorless tasks are more beneficial than errorful tasks in the treatment of aphasia

Why might we doubt this simple conclusion?

1) Can we be sure the errorless task was more accurate?

2) If it is the errorless nature of the task that is important then within a task the more accurate that task the greater the benefit for naming.

Is this the case …

across people?

YES

The more errorless, the more benefit?

Examine at the correspondence between accuracy of the task (repetition/cueing) and the amount of benefit for naming

-0.20

0.00

0.20

0.40

0.60

0.80

1.00

Repetition - Facilitationaccuracy

Repetition naming benefitOrder the individuals by facilitation task

accuracy and look at whether the naming accuracy shows a parallel

increase

The more errorless, the more benefit?

Examine at the correspondence between accuracy of the task (repetition/cueing) and the amount of benefit for naming

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

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0.9

MFT

DRSFAB

FME

KCCSJS DIP JN

IJM

MM

CBPSJ

JUE

WVK

SMG

JOW

Phon Cue - Facilitationaccuracy

Phon Cue naming benefit

The more errorless, the more benefit?

Examine at the correspondence between accuracy of the task (repetition/cueing) and the amount of benefit for naming

In other words: it is not the case that the more accurate the facilitation task the more naming benefits.

i.e. errorless is not better than errorful WITHIN a task across individuals

 

Pearson’s Correlation (r=)

Significance (p=)

Repetition 0.17 0.539

Phon cue 0.03 0.906

No significant correlation between success of the cue

during facilitation and benefit of cueing for subsequent naming

Conclusion

Errorless tasks are more beneficial than errorful tasks in the treatment of aphasia

Why might we doubt this simple conclusion?

1) Can we be sure the errorless task was more accurate?

2) If it is the errorless nature of the task that is important then within a task the more accurate that task the greater the benefit for naming.

Is this the case …

across people?

within people across items?

YES

NO

Accuracy within task & within individual across items.

• Compared accuracy of items that were accurate in facilitation and those that were not.

• Are the items that are accurate repeated/named with a cue more accurately named 10 minutes later?

• Repetition: Correctly repeated: 47% correctly named

Incorrectly repeated: 23% correctly named

• Phonemic Cueing:

Correctly named with cue: 62% correctly named

Incorrectly named with cue: 18% correctly named

Conclusion

Errorless tasks are more beneficial than errorful tasks in the treatment of aphasia

Why might we doubt this simple conclusion?

1) Can we be sure the errorless task was more accurate?

2) If it is the errorless nature of the task that is important then within a task the more accurate that task the greater the benefit for naming.

Is this the case …

across people?

within people across items?

YES

NO

Yes …but

Summary of present thinking

Errorless learning • An overly simplistic notion……• CANNOT evaluate using two tasks • More sensible to evaluate within a task.

It MAY be the case that items which are more accurate in some therapy tasks that involve output are better named at a later point.

….this is counter to the traditional notion that tasks which are harder and more effortful are more productive.

Maybe not!

Is errorless learning a useful concept in the treatment of word retrieval disorders?