The Imagine Reality Lab

At the Imagine Reality Lab we try to figure out how our brain distinguishes imagination from reality. We aim to answer questions such as: ‘how does the brain conjure vivid mental images?’ and ‘how does it keep imagined content separate from what’s real?’

The lab is based in Department of Imaging Neuroscience, where we use state-of-the-art neuroimaging techniques to measure people’s brain activity while they think, see, feel and imagine. 

We combine brain scanning with carefully curated behavioural paradigms, computational modelling and machine learning to discover neural mechanisms of cognition.

Curiosity-driven basic research

Our lab focuses on curiosity-driven basic research: we try to understand how the brain works and how it gives rise to our vivid experience of imagination and reality.  

Our first goal is not to cure a specific disease, but basic research often lays the foundation for discovering causes or cures for illness. For example, we recently discovered that a specific part of the brain’s visual system, the fusiform gyrus, is important in keeping apart visual imaginations from real seeing. 

In our experiment we found that when activation in this brain region became very strong during imagination, participants started to think that what they were imagining was actually real. 

In ongoing research with collaborators at the Institute and internationally, we are now investigating whether this brain process is altered in people with schizophrenia or Parkinson’s who experience hallucinations.

Our research follows a computational cognitive neuroscience approach. 

We begin by characterising human behaviour in specific experimental contexts. We then try to specify an algorithm for how the underlying cognitive process might work based on this and test whether it can explain the observed behavioural. Finally, we test whether the brain implements the key components of that algorithm. 

As an example, we proposed the ‘reality threshold model’ which suggests that imagined and perceived inputs are combined into a single ‘reality signal.’ When this signal crosses a certain threshold, the brain interprets the content as real. 

This model successfully predicted when participants would mistake imagined lines for real ones in an experiment. We then searched for neural signatures of both the reality signal and the threshold and identified the fusiform gyrus and anterior insula as likely contributors.

By formalising theories as algorithms, we can predict how changes in specific signals should affect behaviour, giving us more precise hypotheses and ultimately allowing us to uncover the mechanisms that underlie cognition.
 

Our research interests

We have a small interdisciplinary team, who are all working together on the overarching question ‘how does our brain determine whether what we see is real or imagined?’. 

Postdoc Giulia is investigating how volitional control influences our sense of reality, asking ‘does the fact that I am choosing what to imagine make it feel less real to me?’

PhD student Paz investigates whether in the real world, we use the context to infer whether something is real: ‘am I more likely to think that an imagined elephant is really there when I am in the desert, than when I am in the office?’

Research assistant Ataol is working on whether a specific type of machine learning algorithm could serve as a model for how children learn to distinguish reality from imagination.

Finally, affiliated postdoc and PhD students, Benjy, Martha, Luna, Dot, and Ryan are all working on different projects investigating top-down influences on conscious experience. 

Our lab ethos

The ethos of our lab is built on a foundation of open, rigorous, and curiosity-driven science combined with a strong emphasis on personal wellbeing. 

We believe that the best science is done by scientists who feel supported and empowered. We recognise that there is a certain level of stress inherent to academic research and actively build strategies to address this stress. 

Lab members are encouraged to take holidays, prioritise a good work-life balance and ask for help when needed and we make sure to make time for social lab activities (like going to the arcade) to create a strong team spirit. 

Ultimately, we aim to create an environment where people from diverse backgrounds and disciplines feel supported to challenge themselves and each other and to pursue their curiosity to discover how our brain creates our minds.

Further information

• Quanta Magazine: Is it Real or Imagined? How Your Brain Tells the Difference
• Imagine Reality lab website
• Dr Nadine Dijkstra profile