Jennifer Wallis

Face age and sex modulate the other-race effect in face recognition.

Faces convey a variety of socially relevant cues that have been shown to affect recognition, such as age, sex, and race, but few studies have examined the interactive effect of these cues. White participants of two distinct age groups were presented with faces that differed in race, age, and sex in a face recognition paradigm. Replicating the other-race effect, young participants recognized young own-race faces better than young other-race faces. However, recognition performance did not differ across old faces of different races (Experiments 1, 2A). In addition, participants showed an other-age effect, recognizing White young faces better than White old faces. Sex affected recognition performance only when age was not varied (Experiment 2B). Overall, older participants showed a similar recognition pattern (Experiment 3) as young participants, displaying an other-race effect for young, but not old, faces. However, they recognized young and old White faces on a similar level. These findings indicate that face cues interact to affect recognition performance such that age and sex information reliably modulate the effect of race cues. These results extend accounts of face recognition that explain recognition biases (such as the other-race effect) as a function of dichotomous ingroup/outgroup categorization, in that outgroup characteristics are not simply additive but interactively determine recognition performance.

Characterization of field loss based on microperimetry is predictive of face recognition difficulties.

PURPOSE To determine how visual field loss as assessed by microperimetry is correlated with deficits in face recognition. METHODS Twelve patients (age range, 26-70 years) with impaired visual sensitivity in the central visual field caused by a variety of pathologies and 12 normally sighted controls (control subject [CS] group; age range, 20-68 years) performed a face recognition task for blurred and unblurred faces. For patients, we assessed central visual field loss using microperimetry, fixation stability, Pelli-Robson contrast sensitivity, and letter acuity. RESULTS Patients were divided into two groups by microperimetry: a low vision (LV) group (n = 8) had impaired sensitivity at the anatomical fovea and/or poor fixation stability, whereas a low vision that excluded the fovea (LV:F) group (n = 4) was characterized by at least some residual foveal sensitivity but insensitivity in other retinal regions. The LV group performed worse than the other groups at all blur levels, whereas the performance of the LV:F group was not credibly different from that of the CS group. The performance of the CS and LV:F groups deteriorated as blur increased, whereas the LV group showed consistently poor performance regardless of blur. Visual acuity and fixation stability were correlated with face recognition performance. CONCLUSIONS Persons diagnosed as having disease affecting the central visual field can recognize faces as well as persons with no visual disease provided that they have residual sensitivity in the anatomical fovea and show stable fixation patterns. Performance in this task is limited by the upper resolution of nonfoveal vision or image blur, whichever is worse.

Feasibility of a Web-Based Survey of Hallucinations and Assessment of Visual Function in Patients With Parkinson’s Disease

Background Patients with Parkinson’s disease (PD) experience visual hallucinations, which may be related to decreased contrast sensitivity (ie, the ability to discern shades of grey). Objective The objective of this study was to investigate if an online research platform can be used to survey patients with Parkinson’s disease regarding visual hallucinations, and also be used to assess visual contrast perception. Methods From the online patient community, PatientsLikeMe, 964 members were invited via email to participate in this study. Participants completed a modified version of the University of Miami Parkinson’s disease hallucinations questionnaire and an online vision test. Results The study was completed by 27.9% (269/964) of those who were invited: 56.9% of this group had PD (153/269) and 43.1% (116/269) were non-Parkinson’s controls. Hallucinations were reported by 18.3% (28/153) of the Parkinson’s group. Although 10 subjects (9%) in the control group reported experiencing hallucinations, only 2 of them actually described formed hallucinations. Participants with Parkinson’s disease with a mean of 1.75 (SD 0.35) and the control group with a mean of 1.85 (SD 0.36) showed relatively good contrast perception as measured with the online letter test (P=.07). People who reported hallucinations showed contrast sensitivity levels that did not differ from levels shown by people without hallucinations (P=.96), although there was a trend towards lower contrast sensitivity in hallucinators. Conclusions Although more Parkinsons responders reported visual hallucinations, a significant number of non-Parkinsons control group responders also reported visual hallucinations. The online survey method may have failed to distinguish between formed hallucinations, which are typical in Parkinsons disease, and non-formed hallucinations that have less diagnostic specificity. Multiple questions outlining the nature of the hallucinations are required. In a clinical interview, the specific nature of the hallucination would be further refined to rule out a vague description that does not indicate a true, formed visual hallucination. Contrary to previous literature, both groups showed relatively good contrast sensitivity, perhaps representing a ceiling effect or limitations of online testing conditions that are difficult to standardize. Steps can be taken in future trials to further standardize online visual function testing, to refine control group parameters and to take steps to rule out confounding variables such as comorbid disease that could be associated with hallucinations. Contacting subjects via an online health social network is a novel, cost-effective method of conducting vision research that allows large numbers of individuals to be contacted quickly, and refinement of questionnaires and visual function testing may allow more robust findings in future research.

Visual Function in the Oldest-Old 1 Year After Comprehensive Vision Rehabilitation

More than one-third of the LTC residents sampled had GNB isolated from their oropharynx. This rate was three times as high as in community-dwelling older persons of similar age and sex. These findings are in keeping with those previously published. Although LTC residents had a higher incidence of LRTI in the year before sampling and received more antibiotics, no association was found between these factors and the isolation of GNB. Novel findings from this study include the association between polypharmacy, IHD, and GNB isolation, which was independent of age and residence in a LTC facility. Recent antibiotic use was not identified as a risk factor, but detailed analysis of the other medication classes associated with GNB isolation was beyond the scope of this study. Underlying disease and xerostomia-inducing medications are associated with low salivary flow, which has in turn been linked with oropharyngeal bacterial colonization. One explanation for this is that less saliva leads to smaller quantities of buccal-cell fibronectin. An inverse relationship between fibronectin and adherence of GNB to buccal mucosal cells has been demonstrated. Greater attention to oral hygiene and polypharmacy is required, particularly in residents of LTC facilities who are dependent on others for oral care, to reduce the risk of GNB colonization.