Local but not long-range microstructural differences of the ventral temporal cortex in developmental prosopagnosia

Abstract

Individuals with developmental prosopagnosia (DP) experience face recognition impairments despite normal intellect and low-level vision and no history of brain damage. Prior studies using diffusion tensor imaging in small samples of subjects with DP (n=6 or n=8) offer conflicting views on the neurobiological bases for DP, with one suggesting white matter differences in two major long-range tracts running through the temporal cortex, and another suggesting white matter differences confined to fibers local to ventral temporal face-specific functional regions of interest (fROIs) in the fusiform gyrus. Here, we address these inconsistent findings using a comprehensive set of analyzes in a sample of DP subjects larger than both prior studies combined (n=16). While we found no microstructural differences in long-range tracts between DP and age-matched control participants, we found differences local to face-specific fROIs, and relationships between these microstructural measures with face recognition ability. We conclude that subtle differences in local rather than long-range tracts in the ventral temporal lobe are more likely associated with developmental prosopagnosia.

Word and text processing in developmental prosopagnosia

“…This is that developmental prosopagnosia is due to some anomaly involving the fusiform gyrus. Some find subtle abnormalities in the activation or structure of the right posterior fusiform gyrus (Furl, Garrido, Dolan, Driver, & Duchaine, 2011;Garrido et al, 2009;Hadjikhani & de Gelder, 2002;Song et al, 2015). Others find normal activation of the fusiform face area and other components of the core face network (Avidan et al, 2014;Thomas et al, 2009), which may be consistent with other studies that report abnormal connectivity with more anterior temporal structures (Avidan et al, 2014;Gomez et al, 2015;Thomas et al, 2009).…”

The Definition and Diagnosis of Developmental Prosopagnosia

“…Alternatively, if actual differences in processing strategy or biological markers of DP and super-recognition are observed, this would be stronger evidence that the two terms refer to qualitatively different groups of people. There is some evidence to support this in individuals with DP, given recent neurological findings that suggest structural atypicalities within critical regions implicated in face-processing (e.g., Behrmann, Avidan, Gao, & Black, 2007;Burns, Tree, & Weidemann, 2014;Garrido et al, 2009;Song et al, 2015).…”

Prosopagnosia: current perspectives

“…Others maintain that the core face network is largely normal and that abnormalities lie instead in the anterior temporal cortex,134,135 other regions of the extended face network,136 or the long-range white matter tracts that connect the core regions in occipitotemporal cortex with the anterior temporal face area, namely the inferior longitudinal fasciculus 134,137. Both groups claim that the degree of altered white matter connectivity in their results correlated with behavioral measures of impaired face recognition 133,137. Whether these discrepancies reflect a real heterogeneity that exists in developmental prosopagnosia remains to be determined.…”