Work Package 2

Does increasing the amount of "good" bacteria in the gut improve task performance and affect brain function?

What's involved?

Work Package 2 is a randomised, placebo-controlled, cross-over study investigating the effects of probiotics on brain and behaviour measures. This study will include 60 healthy male volunteers from Study 1 and will involve 4 study visits. People who take part in this study will be asked to provide faecal, urine and blood samples for biological analysis, complete a small number of behavioural tasks and questionnaires, and undergo four MRI scans at the Centre for Integrative Neuroscience and Neurodynamics, University of Reading. Participants will be tested before and after taking a placebo and a probiotic supplement selected to temporarily change the bacterial population in the gut.


If you would like to take part in the study, please follow this link to see if you are eligible

What are probiotics?

Probiotics are live microorganisms (bacteria or yeast) that can benefit your health by improving or restoring the gut flora. A healthy gut microbiome may help to prevent or treat diseases but there is much more research needed to understand if and how taking probiotics affects brain function. Volunteers participating in Work Package 2 will be asked to take a commercially available probiotic that has been carefully chosen by the researchers. We would like to test if this probiotic has any effect on the brain and behaviour.

MRI scan

Magnetic Resonance Imaging (MRI) is a non-invasive tool for imaging the living brain. Using MRI, we can visualise different kinds of tissue, measure changes in blood flow, and estimate levels of chemicals your brain uses to function properly. The MRI scan will take 1 hour, during which you can lie back and relax.

Biological samples

There are around 100,000,000,000,000 microorganisms in the human gut! That's more than the number of cells in your entire body.

To measure the levels of bacteria and the chemicals they produce in the gut, we will ask you to provide small samples of faeces, urine and blood for analysis.


Behavioural tasks

The gut produces chemicals that are identical to the chemicals produced by your brain. To help us understand whether the bacterial environment in your gut can affect your behaviour and performance, we'll ask you to complete some simple computer-based tasks. We'll also ask you to answer some questions about your eating habits, emotions and general wellbeing.