Dean is a lecturer in developmental psychology at City, University of London.

Fascinated by human development, Dean completed a PhD at the Centre for Brain and Cognitive Development, Birkbeck, University of London. This focused on the early cognitive and neurophysiological processes that underlie cognitive and language development in infants at high risk of autism and children with different neurodevelopmental disorders. In 2017, he set up the Early Learning and Neurodevelopment lab (the ELAN lab), which investigates mechanisms of developmental change in typical and atypical populations.