Files and links (1)
Accepted VersionCC BY V4.0, Open Access
Journal article
The effect of Huntington's disease on cognitive and physical motivation
Brain, Vol.147(7), pp.2449-2458
2024
PMID: 38266149
Appears in Thompson Institute Research Collection
Abstract
Apathy is one of the most common neuropsychiatric features of Huntington's disease (HD). A hallmark of apathy is diminished goal-directed behaviour, which is characterised by a lower motivation to engage in cognitively or physically effortful actions. However, it remains unclear whether this reduction in goal-directed behaviour is driven primarily by a motivational deficit, and/or is secondary to the progressive cognitive and physical deficits that accompany more advanced disease. We addressed this question by testing 17 individuals with manifest HD and 22 age-matched controls on an effort-based decision-making paradigm. Participants were first trained on separate cognitively and physically effortful tasks, and provided explicit feedback about their performance. Next, they chose on separate trials how much effort they were willing to exert in each domain in return for varying reward. At the conclusion of the experiment, participants were asked to rate their subjective perception of task load. In the cognitive task, the HD group were more averse to cognitive effort than controls. Although the HD group were more impaired than controls on the task itself, their greater aversion to cognitive effort persisted even after controlling for task performance. This suggests that the lower levels of cognitive motivation in the HD group relative to controls was most likely driven by a primary motivational deficit. In contrast, both groups expressed a similar preference for physical effort. Importantly, the similar levels of physical motivation across both groups occurred even though participants with HD performed objectively worse than controls on the physical effort task, and were aware of their performance through explicit feedback on each trial. This indicates that the seemingly preserved level of physical motivation in HD was driven by a willingness to engage in physically effortful actions despite a reduced capacity to do so. Finally, the HD group provided higher ratings of subjective task demand than controls for the cognitive (but not physical) effort task, and when assessing the mental (but not the physical) load of each task. Together, these results revealed a dissociation in cognitive and physical motivation deficits between HD and controls, which were accompanied by differences in how effort was subjectively perceived by the two groups. This highlights that motivation is the final manifestation of a complex set of mechanisms involved in effort processing, which are separable across different domains of behaviour. These findings have important clinical implications for the day-to-day management of apathy in HD.
Details
- Title
- The effect of Huntington's disease on cognitive and physical motivation
- Authors
- Kelly J Atkins (Author) - Monash UniversitySophie C Andrews (Author) - University of the Sunshine Coast, Queensland, Thompson InstituteJulie C Stout (Author) - Monash UniversityTrevor T-J Chong (Corresponding Author) - Monash University
- Publication details
- Brain, Vol.147(7), pp.2449-2458
- Publisher
- Oxford University Press
- Date published
- 2024
- DOI
- 10.1093/brain/awae023
- ISSN
- 1460-2156; 0006-8950
- PMID
- 38266149
- Copyright note
- © The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
- Grants
- Grant note
- K.J.A. was supported by the Australian Government Research Training Scheme. J.S. is supported by the National Health and Medical Research Council of Australia.
- Organisation Unit
- Healthy Ageing Research Cluster; Thompson Institute
- Language
- English
- Record Identifier
- 99995998902621
- Output Type
- Journal article
Metrics
1 File views/ downloads
31 Record Views