Thomas' primary research interest concerns how people remember to perform actions in the future, which is known in the literature as 'prospective memory'. This behaviour can be studied both at the cognitive level by looking at factors such as attention and memory, as well as at a social-cognitive level, considering things such as motivation and perceived importance. In particular, Thomas is interested in how emotion interacts with cognition in these situations. For example, could eliciting the feeling of disgust help people to remember to wash their hands? Do emotional cues in the environment help to trigger our memory to do things?
In addition, Thomas has done research into the phenomenon of Autonomous Sensory Meridian Response (ASMR) - a feeling of calmness accompanied by a tingling sensation on the scalp which is commonly triggered by cues such as whispering and close personal attention.