Distinct mechanisms mediate speed-accuracy adjustments in cortico-subthalamic networks
- University of Oxford, United Kingdom
- Kings College London, United Kingdom
- University College London Institute of Neurology, United Kingdom
Abstract
Optimal decision-making requires balancing fast but error-prone and more accurate but slower decisions through adjustments of decision thresholds. Here, we demonstrate two distinct correlates of such speed-accuracy adjustments by recording subthalamic nucleus (STN) activity and electroencephalography in eleven Parkinson’s disease patients during a perceptual decision-making task; STN low-frequency oscillatory (LFO) activity (2-8 Hz), coupled to activity at prefrontal electrode Fz, and STN beta activity (13-30 Hz) coupled to electrodes C3/C4 close to motor cortex. These two correlates not only differed in their cortical topography and spectral characteristics, but also in the relative timing of recruitment and in their precise relationship with decision thresholds. Increases of STN LFO power preceding the response predicted increased thresholds only after accuracy instructions, while cue-induced reductions of STN beta power decreased thresholds irrespective of instructions. These findings indicate that distinct neural mechanisms determine whether a decision will be made in haste or with caution.
Data availability
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Neural correlates of speed-accuracy adjustments in the subthalamic nucleusPublicly available at Oxford University Research Archive (uuid: 09bef38c-999f-4fb7-aa46-14eda3123571).
Article and author information
Author details
Funding
Medical Research Council (MC_UU_12024/1)
- Peter Brown
Horizon 2020 Framework Programme (655605)
- Damian M Herz
Parkinson Appeal UK
- Thomas Foltynie
- Patricia Limousin
- Ludvic Zrinzo
Monument Trust
- Thomas Foltynie
- Patricia Limousin
- Ludvic Zrinzo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: In accordance with the declaration of Helsinki, participants gave written informed consent to participate in the study, which was approved by the local ethics committee (Oxfordshire REC A).
Copyright
© 2017, Herz et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Distinct mechanisms mediate speed-accuracy adjustments in cortico-subthalamic networks
eLife 6:e21481.
https://doi.org/10.7554/eLife.21481
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