Every day, we make decisions based on incomplete information. But how do we decide when we have gathered enough evidence to make up our minds? Some people tend to decide very quickly, while others continue gathering information long after enough evidence is available. These differences in information gathering are particularly pronounced in mental health conditions such as schizophrenia and obsessive-compulsive disorder (OCD).
The Deciding2Decide project investigates why these decision-making biases arise, how they are implemented in the brain, and whether they can be changed. We combine computational modelling with large-scale behavioural studies, neuroimaging, clinical research and experiments in rodents. By studying the same fundamental decision processes across different methods, populations and species, we aim to build a mechanistic understanding of information gathering that can ultimately inform new approaches to treatment.
Why do some people make decisions with very little information, while others keep searching for more? Behaviour alone cannot tell us which processes give rise to these differences.
We use computational models to break information gathering down into its underlying components. These models allow us to investigate how people weigh new evidence, how confident they are in their decisions, and what determines when they stop gathering information and make a choice.
A common computational framework connects the different parts of Deciding2Decide, allowing us to compare decision-making mechanisms across behavioural experiments, neuroimaging, clinical populations and animal studies.
Understanding why decision-making biases occur is only the first step. We also want to investigate whether they can be changed.
We develop and test brief psychological interventions designed to increase awareness of decision-making biases and promote more adaptive ways of gathering and evaluating information. After initially testing and refining these approaches online, we will investigate whether they can alter information-gathering behaviour in people with OCD and schizophrenia.
In parallel, we investigate the role of dopamine pharmacologically in healthy participants. Together with our cross-species research, these studies will help us determine which cognitive and neurobiological mechanisms are potentially modifiable and may ultimately provide new directions for more targeted interventions.
What happens in the brain while we gather information and decide when enough is enough?
Using functional magnetic resonance imaging (fMRI), we investigate the neural mechanisms underlying information-gathering biases in people with obsessive-compulsive disorder (OCD), schizophrenia and individuals without a psychiatric diagnosis. Rather than studying diagnostic categories in isolation, we take a transdiagnostic approach to identify mechanisms that may be shared across different mental health conditions.
The study is conducted in parallel in Tübingen and Bengaluru, allowing us to investigate these mechanisms across different cultural and socioeconomic contexts. Combining brain imaging with computational modelling will help us determine whether apparently different decision-making biases arise from shared or distinct neural processes.
To understand the brain mechanisms behind information gathering in greater detail, we study related decision processes in mice.
Using a specially developed behavioural task, mice gather visual information before making a decision. This allows us to examine whether the fundamental computational principles identified in humans can also be observed in another species.
We focus particularly on the role of dopamine, a neurotransmitter involved in learning and decision-making. By recording dopamine activity in the prefrontal cortex and striatum and experimentally manipulating these signals, we can test their causal role in information gathering. Linking these experiments to the same computational framework used in our human studies enables us to connect behaviour, brain mechanisms and computation across species
Research on mental health should be shaped by the perspectives of people who have direct experience of the conditions being studied.
People with lived experience are therefore involved throughout Deciding2Decide, contributing to decisions about how our studies are designed, conducted, interpreted and communicated. Lived Experience Representatives are part of the project's decision-making structures, and local panels in Germany and India provide ongoing input into our clinical research.
We are also working together with people with lived experience on public engagement activities, including a project exploring questions and perspectives around the use of animal research in mental health research. This collaborative approach helps ensure that our research remains relevant, accessible and connected to the priorities of the people it ultimately aims to benefit.
