What do we know about people with developmental prosopagnosia?

Developmental prosopagnosia (DP) is a severe deficit in recognising facial identity in the absence of known brain damage or other cognitive, socio-emotional, or low-level visual impairments. Although initially thought to be quite rare, DP has been estimated to affect between 1.0% and 2.5% of the population, with different estimates reflecting different tools and analytical approaches to categorising DP. Research over the last 25 years has identified several cognitive and neural mechanisms that appear to contribute to face recognition deficits in DP, and both structural and functional neural differences have been found between individuals with DP and neurotypical participants. Nevertheless, clear neurocognitive signatures of this condition remain elusive, likely due to a) the high degree of individual variability observed in the behavioural and cognitive profiles of individuals with DP and b) the focus on group-based analyses rather than on in-depth, individual-level investigations. We recommend that future studies emphasise the latter approach.