Research | Nura Sidarus

RESEARCH SUMMARY

I’m a lecturer in the Department of Psychology, at Royal Holloway University of London. I am interested in understanding how we make decisions and how we come to feel in control of our actions and their consequences, i.e. have a sense of agency. Our experience of agency is foundational to our societal notions of responsibility and freedom of choice.

Using behavioural, computational, and neuroimaging methods, I investigate influences on learning and decision-making, e.g. due to distracting stimuli, freedom of choice, confidence in a decision (aka metacognition), and how these also interact with our sense of agency. Moreover, I'm starting to explore how these (meta)cognitive processes may become maladaptive and underlie psychiatric symptoms, such as depression, thanks to an ESRC New Investigator Grant (details here).

During my postdoctoral research, thanks to a Fyssen Foundation Fellowship, I moved to the Institut Jean Nicod, and then to Laboratoire de Neurosciences Cognitives et Computationnelles, at ENS, PSL Université Paris. Here, I investigated how we monitor our decisions and our actions, and how decision-making processes interact with learning about action outcomes, and with the sense of agency. I additionally started investigating how learning is influenced by freedom of choice. I developed new skills in computational modelling (reinforcement learning) and fMRI.

I completed my PhD at the Institute of Cognitive Neuroscience, University College London, under the supervision of Prof Patrick Haggard. During my PhD, I focussed on how action selection processes inform our experience of agency, independently of monitoring the outcomes of action. I used a variety of tasks to manipulate action selection, both consciously and unconsciously. Additionally, I used EEG to investigate the neural mechanisms underlying the sense of agency.

SOME KEY QUESTIONS AND STUDIES

How choice freedom and difficulty influence decisions and learning

Can we be biased by irrelevant external suggestions, when making internally motivated choices?

We recently found that people could be biased by external suggestions, when they weren't too sure what they should do. This avoids effortful conflict between internal and external drives to actions.

When in doubt, why not "go with the flow"?

Do we learn differently when we can freely choose what to do than when following instructions?

We found that people tended to learn less well when they had to follow instructions than when they could choose what to do. They learned even less when they had to follow instructions that they disagreed with. Why bother learning from bad instructions?

Read the full article preprint in BioRxiv.

Hierarchical integration of information for the sense of agency

What information is more important for agency?

Voluntary action can involve multiple, hierarchically organised, levels of intentions and outcomes. For example, in a computer game, your overall goal is to maximise your performance. That requires being able to control the computer mouse to accurately move your cursor as you wish (proximal intention). Sometimes the decisions may also be more or less difficult to make.

Our work showed that, in this context, being able to properly control the mouse (proximal level) was the most important cue for the sense of agency. Decision difficulty and overall performance still influenced the sense of agency, but not as much.

Sense of agency relies on the most relevant, and proximal, information.

Read the full article in Frontiers in Psychology.

Impact of social contexts on the sense of agency

Why do we feel less responsible for our actions in
social contexts?

"Diffusion of responsibility" in social contexts is a well known phenomenon, e.g. leading people to be less likely to act when in a group. This is typically explained through a post-hoc, self-serving justification, especially for undesirable outcomes. Yet, social situations can increase ambiguity about who really caused a given outcome.

By designing a task which carefully controlled for those alternatives explanations, our work revealed a new explanation for this effect:

The presence of other agents makes our own decision-making more difficult, as we try to imagine what other people might do. This increased decision-making difficulty in turn reduces our sense of agency, as well as the monitoring of action outcomes.

Worrying about the potential actions of other people can lead to inaction, or feeling less responsible for what we actually do.

Read the full article preprint in SCAN.

How decision difficulty influences the sense of agency

When does the sense of agency emerge?

Our work has shown that our sense of agency is prospectively by our metacognitive monitoring of our decision-making processes.

In a EEG study, we found that this signals that relate to our sense of agency arise already at the time of the action, and long before we know what were the outcomes of our actions. Importantly, this was independent of the contribution of outcome monitoring to agency.

Difficult decisions tend to make us feel less in control.

Can our conscious experience of agency be influenced by unconsciously processed information?

Remarkably, we found these effects while using subliminal priming, i.e. very briefly flashed stimuli that we don't consciously perceive. Nonetheless, the primes do make decision-making more difficulty.

Even if we can't perceive subliminal stimuli, we may feel some consequences of their presentation (e.g. by monitoring our cognition).

Read the full article in NeuroImage.