Rehabilitation and intervention of developmental and acquired prosopagnosia: A systematic review

Prosopagnosia is a neurological disorder; characterized by an impairment in facial recognition. It can occur from acquired prosopagnosia (occurring in approximately 5.6% of the population), or from developmental prosopagnosia (occurring in approximately 2% of the population). Despite the relatively high prevalence of prosopagnosia, there has been limited research into intervention for this condition. The current systematic review aimed to review the evidence base to aid the development of practice guidelines for clinicians working with impacted individuals. A systemic search identified 14 studies, 10 of which involved participants with developmental prosopagnosia, while the remaining studies involved participants with acquired prosopagnosia. Overall, the findings identified two strategies which produced significant improvement in face recognition in prosopagnosics. The first strategy involved a perceptual learning strategy (a restorative approach). While this strategy improved face processing abilities, the intervention was time-consuming and relied on specific software. The second strategy involved learned association of distinguishable facial features (a compensatory approach). This intervention produced improvements in face recognition and was quick to administer, however, the gains made were not generalisable to untrained faces. The current review identified a number of limitations in the existing literature, such as the lack of single-case experimental designs and randomized controlled trials, limited control for practice effects, and no consensus with regard to the assessment and diagnosis of prosopagnosia. This review highlighted the need for further research to inform practice guidelines.