Inhibitory control mechanisms and their role in task switching: A multi-methodological approach

Executive control allows us to ignore distraction and switch between tasks in a flexible, yet organized fashion. While a hallmark of controlled behavior, distinctions among executive control processes are not thoroughly agreed upon. The present work explored the organization of two of these executive control processes, inhibition and shifting, and their relationship to each other. There were two primary goals. The first goal was to investigate the distinction among inhibitory control processes, as “inhibition” has oftentimes been considered a unitary construct. For example, there is evidence that response-distractor inhibition, which involves resolving interference from dominant responses or distractors in the external environment, is different from resistance to proactive interference (PI), which involves overcoming interference from previously relevant representations in memory. Using aging, neuropsychology, and individual differences methodologies, I investigated the unity and diversity of inhibitory control mechanisms. The healthy aging and neuropsychological evidence supported a distinction between response-distractor inhibition and resistance to proactive interference. However, when controlling for processing speed, the individual differences work suggested a need for further specification, as only a subset of these tasks emerged in the single factor model that provided the best fit to the data. The second goal was to explore how inhibitory control processes interact with task switching, as some theoretical accounts of task switching have suggested that switch costs result from the need to overcome interference from the previously relevant task. Inconsistent with these theories, I found little relation between inhibitory control and measures of global and local task switching, and instead, working memory served as the best predictor of these shifting measures. In contrast, inhibitory control was related to the backward inhibition abilities of older adults. These findings are discussed within a theory of working memory that accounts for the patterns of results found across the different methodologies.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Social Sciences

Grantor

Rice University

Year dc:date.issued

2013

Author dc:creator

• Allen, Corinne

Advisor dc:contributor.advisor

• Martin, Randi C.

Committee members dc:contributor.committeemember

• Schnur, Tatiana T.
• Oswald, Frederick L.
• Kemmer, Suzanne E.
• Basak, Chandramallika

• Inhibition
• Proactive interference
• Task switching
• Individual differences
• Aging
• Neuropsychology

Statement dc:rights

• Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1911/71128

OAI identifier oai:identifier

oai:repository.rice.edu:1911/71128