Neurobehavioural causes and consequences of pupil-linked arousal
Loading...
Author / Producer
Date
2023
Publication Type
Doctoral Thesis
ETH Bibliography
yes
Citations
Altmetric
Data
Rights / License
Abstract
Pupil measurements have been used as a proxy for arousal state in psychological experiments for more than a century. As such, a large body of evidence has been accumulated about the role of arousal in many cognitive functions. One such function is in modulating the aptitude of learning stimulus-reward associations and their values. During such tasks, humans and other organisms are often observed to behave in ways that seem suboptimal. However, recent approaches have shown that this seemingly suboptimal behaviour could be beneficial, when limited information processing resources of organisms are considered. The role of pupil-linked arousal in learning resource-rational behaviours is unclear, and the neural changes associated with pupil-liked arousal are only partly known. This thesis aims to address these gaps in knowledge. The first part of the thesis aimed to establish a paradigm, where learning of stimulus-reward associations in a discrimination task could be studied in a resource rational paradigm in mice. This included making pupil recordings of behaving mice and examining whether the changes in pupil size are associated with different behavioural parameters in the task. Through these novel approaches, and combined with mathematical modelling, we found that mice act as resource-rational agents, optimising their behaviour to maximise utility under the constraint of limited processing resources. We also discovered novel correlates of pupil-linked arousal to behaviour, where we show that arousal systems seem to carry information about reward distribution of sensory cues, as well as relate it to the learning of these distributions. In the second part of the thesis, using correlative and causative methods, we aimed to investigate the role of lateral hypothalamic orexin neurons in the control of pupil size. The orexin neurons have been long associated with arousal and reward cue processing but have not been formally and specifically linked to pupil-linked arousal. We found that activation of orexin neurons causes pupil dilation, and that blocking orexin function leads to specific disturbances in normally observed pupil size fluctuations. Furthermore, we untangled hypothalamus-locus coeruleus circuitry which could be mediating this effect. Overall, the findings in this thesis thus advance our understanding of the neural causes of pupil-linked arousal, as well as its role in learning stimulus-reward associations in a resource rational paradigm.
Permanent link
Publication status
published
External links
Editor
Contributors
Book title
Journal / series
Volume
Pages / Article No.
Publisher
ETH Zurich
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Neuroscience/ neurobiology
Organisational unit
09589 - Burdakov, Denis / Burdakov, Denis