Neural mechanisms of developmental prosopagnosia

• Applicant: Professorin Dr. Katharina von Kriegstein
• Subject Area: Human Cognitive and Systems Neuroscience
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 447320582

Developmental prosopagnosia (DP) is a prevalent life-long socially debilitating disorder that affects the ability to recognise faces, even those of high familiarity, including family members. To date, there is dissensus on the neural mechanisms of DP. The two main opposing theories assume either (i) a local dysfunction of face-sensitive occipitotemporal areas which support the perception and integration of face features (i.e., occipital face area, OFA and fusiform face area, FFA) or (ii) atypical connectivity between the (normally functioning) OFA/FFA and an extended system of brain regions including the anterior temporal lobe face area (aTL-FA). The aTL-FA is a potentially critical region for more abstract computations supporting face-identity recognition. Here, we propose that the conflicting theories on DP may be driven by two shortcomings of previous studies – failure to address the heterogeneous nature of face processing deficits across DP cases and the use of functional magnetic resonance imaging (fMRI) sequences that are suboptimal for imaging the aTL-FA. In our proposal, we plan to (i) systematically characterise individual DP cases based on behavioural assessments which reflect the hierarchical nature of face-identity processing i.e., from perception to recognition; (ii) adopt a novel fMRI sequence that we have recently developed for robustly imaging the aTL-FA and OFA/FFA and (iii) use comprehensive functional and structural (i.e., diffusion weighted imaging) paradigms to systematically examine the neural architecture of face-sensitive brain regions in DP cases and pairwise-matched controls. Based on recent behavioural reports, we expect to characterise two subtypes of DP: a deficit in face-identity perception (apperceptive DP) and a deficit in face-identity recognition, with intact face perception (associative DP). We hypothesise that the dysfunctional neural systems in DP will differ based on the behavioural phenotype: atypical recruitment of the OFA/FFA in apperceptive DP; atypical recruitment of the aTL-FA, and/or atypical structural connectivity to this region, in associative DP. Such results would adjudicate between the opposing theories on the neural basis of DP by showing that both are correct depending on the behavioural phenotype of the disorder. Due to the comprehensive experimental testing and the novel fMRI sequence, the studies will also offer major steps forward in our understanding on how face-identity processing is achieved in the typically developed human brain.

• DFG Programme: Research Grants
• Co-Investigator: Dr. Corrina Maguinness