When does a strategy intervention overcome a failure of inhibition? Evidence from two left frontal brain tumour cases

Robinson, Gail A., Walker, David G., Biggs, Vivien and Shallice, Tim (2016) When does a strategy intervention overcome a failure of inhibition? Evidence from two left frontal brain tumour cases. Cortex, 79 123-129. doi:10.1016/j.cortex.2016.03.011


Author Robinson, Gail A.
Walker, David G.
Biggs, Vivien
Shallice, Tim
Title When does a strategy intervention overcome a failure of inhibition? Evidence from two left frontal brain tumour cases
Journal name Cortex   Check publisher's open access policy
ISSN 0010-9452
1973-8102
Publication date 2016-06
Year available 2016
Sub-type Article (original research)
DOI 10.1016/j.cortex.2016.03.011
Open Access Status Not Open Access
Volume 79
Start page 123
End page 129
Total pages 7
Place of publication Amsterdam, Netherlands
Publisher Elsevier
Collection year 2017
Language eng
Formatted abstract
Introduction
Initiation and inhibition of responses are crucial for appropriate behaviour across different settings. Initiation and inhibition difficulties are well documented following frontal damage, although task differences have limited our understanding. The Hayling Sentence Completion Test was designed to assess verbal initiation and inhibition within the same task. This study investigates the ability of two patients with left frontal tumours (KI: high grade glioma; PM: meningioma) to use a strategy to overcome profound suppression failures on the Hayling Test.

Method
KI and PM completed the Hayling Test and two experimental tasks. The Selection Investigation assessed verbal initiation on a sentence completion task that varied selection demands (high/low). The Suppression and Strategy Investigation assessed ability to implement four strategies aimed to override a suppression failure and facilitate production of an unconnected word.

Results
On the Hayling Test, KI and PM initiated responses to complete high constraint sentences, in contrast to impaired suppression. KI benefitted minimally from strategies to overcome suppression failure although one strategy (object naming) was partially successful. KI's errors revealed fast suppression errors, in contrast to slow no responses, and selection ability was also impaired for verbal initiation. PM, however, implemented each strategy 100% to overcome a suppression failure and had no difficulty completing sentences meaningfully, regardless of selection demands.

Conclusion
This first investigation of strategy implementation to overcome profound suppression impairments provides insights into verbal initiation, inhibition, selection and strategy mechanisms, which has implications for neurorehabilitation. Specifically, both patients had profound inhibition deficits but KI also presented with a selection deficit and was unable to implement a strategy. By contrast, PM's selection ability was intact but she was unable to generate, rather than implement, a strategy. We suggest that KI has both fast, uncontrolled semantic output and response inhibition difficulty, whereas PM's difficulty is underpinned by motivational factors.
Keyword Suppression
Inhibition
Initiation
Strategy
Hayling Test
Lesion
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: HERDC Pre-Audit
School of Psychology Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 0 times in Thomson Reuters Web of Science Article
Scopus Citation Count Cited 0 times in Scopus Article
Google Scholar Search Google Scholar
Created: Sun, 03 Jul 2016, 00:27:42 EST by System User on behalf of School of Psychology