A new approach to diagnosing and researching developmental prosopagnosia: Excluded cases are impaired too

Developmental prosopagnosia is characterized by severe, lifelong difficulties when recognizing facial identity. Unfortunately, the most common diagnostic assessment (Cambridge Face Memory Test) misses 50–65% of individuals who believe that they have this condition. This results in such excluded cases’ absence from scientific knowledge, effect sizes of impairment potentially overestimated, treatment efficacy underrated, and may elicit in them a negative experience of research. To estimate their symptomology and group-level impairments in face processing, we recruited a large cohort who believes that they have prosopagnosia. Matching prior reports, 56% did not meet criteria on the Cambridge Face Memory Test. However, the severity of their prosopagnosia symptoms and holistic perception deficits were comparable to those who did meet criteria. Excluded cases also exhibited face perception and memory impairments that were roughly one standard deviation below neurotypical norms, indicating the presence of objective problems. As the prosopagnosia index correctly classified virtually every case, we propose it should be the primary method for providing a diagnosis, prior to subtype categorization. We present researchers with a plan on how they can analyze these excluded prosopagnosia cases in their future work without negatively impacting their traditional findings. We anticipate such inclusion will enhance scientific knowledge, more accurately estimate effect sizes of impairments and treatments, and identify commonalities and distinctions between these different forms of prosopagnosia. Owing to their atypicalities in visual perception, we recommend that the prosopagnosia index should be used to screen out potential prosopagnosia cases from broader vision research

Friend effects framework: Contrastive and hierarchical processing in cheerleader effects

Cheerleader effects, group attractiveness effects, and divisive normalization are all characterized by faces appearing more attractive when seen within a group. However, it is possible that your friends could have a detrimental effect upon your attractiveness too: if these group effects arose partly as a contrastive process between your face and your friends, then highly attractive friends may diminish your attractiveness. We confirm this hypothesis across two experiments by showing that the presence of highly attractive friends can indeed make you appear less attractive (i.e., a reverse cheerleader effect), suggesting friend effects are driven in part by a contrastive process against the group. However, these effects are also influenced by your own attractiveness in a fashion that appears consistent with hierarchical encoding, where less attractive targets benefit more from being viewed in an increasingly unattractive group than attractive targets. Our final experiment demonstrates that the company of others not only alters our attractiveness, but also induces shifts in how average or distinctive a target face appears too, with these averageness effects associated with the friend effects observed in our first experiment. We present a Friend Effects Framework within which ‘friend effects’ is an umbrella term for the positive (e.g., cheerleader effects, group attractiveness effects) and negative (i.e., the reverse cheerleader effect) ways in which hierarchical encoding, group contrastive effects, and other influences of friends can have on your attractiveness

Education in the Civilian Conservation Corps Camps in Tennessee

In the preceding chapters an attempt has been made to picture the place of education in the COC camps in Tennessee, to show the physical equipment in the school program, to make clear the duties and qualifications of the Camp Educational Advisor, to point out the background of the enrollees, and to depict the educational program in academic, vocational, and job training. One might well ask about the results of the entire program as the enrollee is affected. Such material as is available will be given in this chapter

Temporal and spatial ensemble statistics are formed by distinct mechanisms

Our brains can extract a summary representation of the facial characteristics provided by a group of faces. To date, there has been a lack of clarity as to what calculations the brain is actually performing during this ensemble perception. For example, does ensemble processing average the fiducial points (e.g., distance between the eyes, width of the mouth) and surface characteristics (e.g., skin tone) of a set of faces in a fashion that produces what we call a ‘morph average’ face from the group? Or does ensemble perception extract a general ‘gist average’ of the face set (e.g., these faces are unattractive)? Here, we take advantage of the fact that the ‘morph average’ face derived from a group of faces is more attractive than the ‘gist average’. If ensemble perception is performing morph averaging, then the adaptation aftereffects elicited by a morphed average face from a group should be equivalent to those elicited by the group. By contrast, if ensemble perception reflects gist averaging, then the aftereffects produced by the group should be distinct from those elicited by the more attractive morphed average face. In support of the morph averaging hypothesis, we show that the adaptation aftereffects derived via temporal ensemble perception of a group of faces are equal to those produced by the group's morphed average face. Moreover, these effects increase as a linear function of increasing attractiveness in the underlying group. We also reveal that spatial ensemble processing is not equal to temporal ensemble processing, but instead reflects the ‘gist’ attractiveness of the group of faces; e.g., these faces are unattractive. Finally, gist averaging of a spatially presented group of faces is abolished when a temporal manipulation is additionally employed; under these circumstances, morph averaging becomes apparent again. In summary, we have shown for the first time that temporal and spatial ensemble statistics reflect qualitatively different perceptual calculations.Ministry of Education (MOE)Nanyang Technological UniversitySupported by Nanyang Technological University Research Scholarship (HY), Undergraduate Research Experience on Campus (AC), College of Arts, Humanities and Social Sciences Incentive Scheme (HX), and Ministry of Education - Singapore Academic Research Fund (AcRF) Tier 1 (HX). H. Ying is also supported by the Ministry of Education - China Project of Humanities and Social Sciences (19YJC190030), the City & University strategy-Soochow University Leading Research Team in Humanities and Social Sciences. Parts of this research (data from Exp 1) were presented at the Annual Meeting of Visual Science Society (VSS), May 2017, St. Pete Beach, Florida. The research reported here forms part of H. Ying's Ph.D. thesis at Nanyang Technological University

Impaired processing of facial happiness, with or without awareness, in developmental prosopagnosia

Developmental prosopagnosia (DP) is associated with severe, lifelong deficits in face recognition, with such cases often cited as support for a dissociation between the processing of facial identity and emotion. Here we examine the evidence against this dissociation and propose that the processing of facial happiness, either with or without awareness, is actually integrated within the same neural network involved in facial identity recognition. We also test this hypothesis on a group of DP cases and neurotypical controls (NT) by adapting them to expressionless neutral faces, intact happy faces and hybrid faces. Despite these hybrid faces being explicitly identified as expressionless due to their higher spatial frequencies taken from a neutral face, their low spatial frequencies convey happy facial expressions that participants are unaware of. After adaptation, participants were asked to judge the facial expressions of face stimuli that were morphed incrementally in varying degrees of sad through to happy. Both groups exhibited emotion adaptation aftereffects to the intact happy faces, although this effect was smaller in DP. Whereas NT produced emotion adaptation aftereffects without awareness of the happy emotion in the hybrid faces; as a group, those with DP did not. Furthermore, our DP cases also exhibited deficits in judging the emotion of the happiest morphed test faces. Our results indicate that the processing of happy facial expressions, with or without awareness, is likely integrated within the face recognition network. We hypothesise that the previously identified abnormalities in the fusiform gyrus in those with DP is the most likely structure responsible for these deficits.MOE (Min. of Education, S’pore)Accepted versio

A new approach to diagnosing and researching developmental prosopagnosia:Excluded cases are impaired too

Developmental prosopagnosia is characterized by severe, lifelong difficulties when recognizing facial identity. Unfortunately, the most common diagnostic assessment (Cambridge Face Memory Test) misses 50–65% of individuals who believe that they have this condition. This results in such excluded cases’ absence from scientific knowledge, effect sizes of impairment potentially overestimated, treatment efficacy underrated, and may elicit in them a negative experience of research. To estimate their symptomology and group-level impairments in face processing, we recruited a large cohort who believes that they have prosopagnosia. Matching prior reports, 56% did not meet criteria on the Cambridge Face Memory Test. However, the severity of their prosopagnosia symptoms and holistic perception deficits were comparable to those who did meet criteria. Excluded cases also exhibited face perception and memory impairments that were roughly one standard deviation below neurotypical norms, indicating the presence of objective problems. As the prosopagnosia index correctly classified virtually every case, we propose it should be the primary method for providing a diagnosis, prior to subtype categorization. We present researchers with a plan on how they can analyze these excluded prosopagnosia cases in their future work without negatively impacting their traditional findings. We anticipate such inclusion will enhance scientific knowledge, more accurately estimate effect sizes of impairments and treatments, and identify commonalities and distinctions between these different forms of prosopagnosia. Owing to their atypicalities in visual perception, we recommend that the prosopagnosia index should be used to screen out potential prosopagnosia cases from broader vision research

Intact word processing in developmental prospagnosia

A wealth of evidence from behavioural, neuropsychological and neuroimaging research supports the view that face recognition is reliant upon a domain-specific network that does not process words. In contrast, the recent many-to-many model of visual recognition posits that brain areas involved in word and face recognition are functionally integrated. Developmental prosopagnosia (DP) is characterised by severe deficits in the recognition of faces, which the many-to-many model predicts should negatively affect word recognition. Alternatively, domain-specific accounts suggest that impairments in face and word processing need not go hand in hand. To test these possibilities, we ran a battery of 7 tasks examining word processing in a group of DP cases and controls. One of our prosopagnosia cases exhibited a severe reading impairment with delayed response times during reading aloud tasks, but not lexical decision tasks. Overall, however, we found no evidence of global word processing deficits in DP, consistent with a dissociation account for face and word processing

Do individual differences in face recognition ability moderate the other ethnicity effect?

Individuals are better at recognizing faces from their own ethnic group compared with other ethnicity faces—the other-ethnicity effect (OEE). This finding is said to reflect differences in experience and familiarity to faces from other ethnicities relative to faces corresponding with the viewers' ethnicity. However, own-ethnicity face recognition performance ranges considerably within a population, from very poor to extremely good. In addition, within-population recognition performance on other-ethnicity faces can also vary considerably with some individuals being classed as “other ethnicity face blind” (Wan et al., 2017). Despite evidence for considerable variation in performance within population for faces of both types, it is currently unclear whether the magnitude of the OEE changes as a function of this variability. By recruiting large-scale multinational samples, we investigated the size of the OEE across the full range of own and other ethnicity face performance while considering measures of social contact. We find that the magnitude of the OEE is remarkably consistent across all levels of within-population own- and other-ethnicity face recognition ability, and this pattern was unaffected by social contact measures. These findings suggest that the OEE is a persistent feature of face recognition performance, with consequences for models built around very poor, and very good face recognizers