Roshan's lab at NVP 2025

Our lab is excited to attend the 2025 Dutch Brain & Cognition Winter Conference in Egmond aan Zee from December 17 to 19. We’ll be participating with presentations and during poster sessions. Come and find us to get to know us and discuss our latest findings!

This year's labmembers & projects:

Helena Olraun: Defining the cortico-striatal mechanisms of selective working memory gating

We investigated how the brain selectively controls what enters and leaves working memory by combining a novel input/output gating task with high-field fMRI. Across studies, we show that working memory gating engages cortico-striatal circuits and produces neural gain in relevant sensory cortex. Crucially, ultra-high-field data reveal preliminary evidence for layer-specific cortical connectivity, suggesting distinct feedforward and feedback mechanisms for input and output gating.

Natalie Nielsen: Distraction-related reduction of ruminative thoughts

Worrying, overthinking, replaying things that happened in the past without finding a solution is called rumination. Rumination is common in anxiety and depression and linked to memory problems. Past research shows that when we recall a memory, it can change. In this study, we tested whether distraction affects negative thoughts more than neutral ones. Participants linked personal thoughts to pictures, after which they focused on one, and were sometimes distracted. After 24 hours, they rated their thoughts again. Negative thoughts became less negative over time, even without such effects during the task. This suggests that the task itself might have helped weaken ruminative thinking 24 hours later.

Egbert Hartstra: Dissociable controllability and value signals in medial frontal cortex and striatum during reinforcement learning

During this talk, I will present the results of a recent fMRI study investigating whether environmental controllability provides the brain with an important source of information for deciding to rely on automatic but inflexible behaviour or on goal-directed but resource-intensive behaviour. Results show that when participants had control over their environment, they relied less on automatic behaviour. Furthermore, fMRI analyses revealed that the medial prefrontal cortex tracks environmental controllability, while action- and state-value signals were observed in dorsal-lateral and ventral-medial striatum. This suggests that the brain tracks both controllability and action-value computations in different brain regions when deciding how to act.

Marwan Engels: Establishing the reliability of a task measuring the impact of controllability on motivation

Motivated behavior depends not only on reward anticipation, but also on beliefs about how much control we have over our environment. We developed a motivational go/no-go task to disentangle controllability from reward value, and, in this study, assess its reliability across sessions. Model-agnostic Bayesian analyses of reliability demonstrate moderate reliability for action-outcome learning. Our next step is employing more complex computational models that capture dissociable trial-wise fluctuations in controllability and reward anticipation to increase test-retest reliability. These findings pave the way for our upcoming transcranial ultrasonic stimulation study where we will target the striatum and pregenual ACC to causally test their causal mechanistic roles in motivation.

Upasana Shah: Disentangling effects of serotonin in Motivation as a function of controllability and reward anticipation

Serotonin has been implicated in motivated behaviour and learned helplessness, with greater release when outcomes are uncontrollable. However, the computational mechanisms by which serotonin shapes motivation remain unclear, as prior studies confound controllability and value. In this poster, I will present ongoing work on a task that dissociates controllability from value while using an SSRI manipulation. Preliminary unblinded analyses suggest higher reward anticipation in low-control/high-value contexts, higher controllability inference in high-control/low-value contexts, and an increased influence of valence on Pavlovian bias as a function of controllability. In the future, we expect to clarify the role of serotonin in decision making by examining how serotonin modulates value, controllability, and motivational biases.

Yanfang Xia: Anticipatory pupil dilation is enhanced by threat and suppressed by control beliefs

We face stressors every day, yet we are not constantly stressed. What are the cognitive mechanisms regulating the perception and response to stressors?

In this talk, I will share evidence that our physiological stress responses are shaped by control beliefs in the environment. Building on work on learned helplessness, we used a shock-avoidance learning task manipulating controllability and stress-relief anticipation. We show that while threat enhances anticipatory pupil dilation, control beliefs suppress it.

Interested in the remarkable power of our minds regulating bodily stress responses? Join the session “Cognitive Control & Executive Functioning” at 10:30 on 19 December 2025 😊