Coping strategies for developmental prosopagnosia.

Developmental prosopagnosia (DP) is a cognitive condition characterised by a relatively selective deficit in face recognition. Some adults and children with DP experience severe psychosocial consequences related to the condition, yet are reluctant to disclose it to others. The remediation of DP is therefore an urgent issue, but has been met with little success. Given that developmental conditions may only benefit from compensatory rather than remedial training, this study aimed to examine (a) the positive and negative effects of DP disclosure, and (b) compensatory techniques that may circumvent recognition failure. Qualitative questionnaires and interviews were carried out with 79 participants: 50 adults with DP, 26 of their non-affected significant others, and three parents of DP children. Findings indicated positive effects of disclosure, yet most adults choose not to do so in the workplace. Effective compensatory strategies include the use of extra-facial information, identity prompts from others, and preparation for planned encounters. However, changes in appearance, infrequent contact, or encounters in unexpected contexts often cause strategy failure. As strategies are effortful and disrupted by heavily controlled appearance (e.g., the wearing of uniform), disclosure of DP may be necessary for the safety, wellbeing and optimal education of children with the condition.

Training face perception in developmental prosopagnosia through perceptual learning.

BACKGROUND: Recent work has shown that perceptual learning can improve face discrimination in subjects with acquired prosopagnosia. OBJECTIVE: In this study, we administered the same program to determine if such training would improve face perception in developmental prosopagnosia. METHOD: We trained ten subjects with developmental prosopagnosia for several months with a program that required shape discrimination between morphed facial images, using a staircase procedure to keep training near each subject's perceptual threshold. To promote ecological validity, training progressed from blocks of neutral faces in frontal view through increasing variations in view and expression. Five subjects did 11 weeks of a control television task before training, and the other five were re-assessed for maintenance of benefit 3 months after training. RESULTS: Perceptual sensitivity for faces improved after training but did not improve after the control task. Improvement generalized to untrained expressions and views of these faces, and there was some evidence of transfer to new faces. Benefits were maintained over three months. Training also led to improvements on standard neuropsychological tests of short-term familiarity, and some subjects reported positive effects in daily life. CONCLUSION: We conclude that perceptual learning can lead to persistent improvements in face discrimination in developmental prosopagnosia. The strong generalization suggests that learning is occurring at the level of three-dimensional representations with some invariance for the dynamic effects of expression.

System for Face Recognition under Different Facial Expressions Using a New Associative Hybrid Model Amαß-KNN for People with Visual Impairment or Prosopagnosia.

Face recognition is a natural skill that a child performs from the first days of life; unfortunately, there are people with visual or neurological problems that prevent the individual from performing the process visually. This work describes a system that integrates Artificial Intelligence which learns the face of the people with whom the user interacts daily. During the study we propose a new hybrid model of Alpha-Beta Associative memories (Amαß) with Correlation Matrix (CM) and K-Nearest Neighbors (KNN), where the Amαß-CMKNN was trained with characteristic biometric vectors generated from images of faces from people who present different facial expressions such as happiness, surprise, anger and sadness. To test the performance of the hybrid model, two experiments that differ in the selection of parameters that characterize the face are conducted. The performance of the proposed model was tested in the databases CK+, CAS-PEAL-R1 and Face-MECS (own), which test the Amαß-CMKNN with faces of subjects of both sexes, different races, facial expressions, poses and environmental conditions. The hybrid model was able to remember 100% of all the faces learned during their training, while in the test in which faces are presented that have variations with respect to those learned the results range from 95.05% in controlled environments and 86.48% in real environments using the proposed integrated system.

Developmental prosopagnosia with concurrent topographical difficulties: A case report and virtual reality training programme.

Several neuropsychological case studies report brain-damaged individuals with concurrent impairments in face recognition (i.e., prosopagnosia) and topographical orientation. Recently, individuals with a developmental form of topographical disorientation have also been described, and several case reports of individuals with developmental prosopagnosia provide anecdotal evidence of concurrent navigational difficulties. Clearly, the co-occurrence of these difficulties can exacerbate the negative psychosocial consequences associated with each condition. This paper presents the first detailed case report of an individual (FN) with developmental prosopagnosia alongside difficulties in topographical orientation. FN's performance on an extensive navigational battery indicated that she primarily has difficulties in the formation and retrieval of cognitive maps. We then evaluated the effectiveness of a short-term virtual reality training programme and found that she is able to form a cognitive map of a particular environment following intense overlearning. Surprisingly, FN's performance on a face recognition task also improved following training. While the latter finding was unexpected and requires further exploration, the training programme reported here may help to alleviate some of the compounded negative psychosocial consequences that are associated with difficulties in finding both locations and people.

The neuropsychological rehabilitation of visual agnosia and Balint's syndrome.

Visual agnosia and Balint's syndrome are complex neurological disorders of the higher visual system that can have a remarkable impact on individuals' lives. Rehabilitation of these individuals is important to enable participation in everyday activities despite the impairment. However, the literature about the rehabilitation of these disorders is virtually silent. Therefore, the aim of this systematic review is to give an overview of available literature describing treatment approaches and their effectiveness with regard to these disorders. The search engines Psychinfo, Amed, and Medline were used, resulting in 22 articles meeting the criteria for inclusion. Only articles describing acquired disorders were considered. These articles revealed that there is some information available on the major subtypes of visual agnosia as well as on Balint's syndrome which practising clinicians can consult for guidance. With regard to the type of rehabilitation, compensatory strategies have proven to be beneficial in most of the cases. Restorative training on the other hand has produced mixed results. Concluding, although still scarce, a scientific foundation about the rehabilitation of visual agnosia and Balint's syndrome is evolving. The available approaches give valuable information that can be built upon in the future.

Perceptual Learning of Faces: A Rehabilitative Study of Acquired Prosopagnosia.

Despite many studies of acquired prosopagnosia, there have been only a few attempts at its rehabilitation, all in single cases, with a variety of mnemonic or perceptual approaches, and of variable efficacy. In a cohort with acquired prosopagnosia, we evaluated a perceptual learning program that incorporated variations in view and expression, which was aimed at training perceptual stages of face processing with an emphasis on ecological validity. Ten patients undertook an 11-week face training program and an 11-week control task. Training required shape discrimination between morphed facial images, whose similarity was manipulated by a staircase procedure to keep training near a perceptual threshold. Training progressed from blocks of neutral faces in frontal view through increasing variations in view and expression. Whereas the control task did not change perception, training improved perceptual sensitivity for the trained faces and generalized to new untrained expressions and views of those faces. There was also a significant transfer to new faces. Benefits were maintained over a 3-month period. Training efficacy was greater for those with more perceptual deficits at baseline. We conclude that perceptual learning can lead to persistent improvements in face discrimination in acquired prosopagnosia. This reflects both acquisition of new skills that can be applied to new faces as well as a degree of overlearning of the stimulus set at the level of 3-D expression-invariant representations.

Congenital prosopagnosia in a child: Neuropsychological assessment, eye movement recordings and training.

Here we report the assessment and treatment of a 6-year-old boy (L.G.) who was referred to us for congenital prosopagnosia (CP). We investigated his performance using a test battery and eye movement recordings pre- and post-training. L.G. showed deficits in recognising relatives and learning new faces, and misrecognition of unfamiliar people. Eye movement recordings showed that L.G. focused on the lower part of stimuli in naming tasks based on familiar or unfamiliar incomplete or complete faces. The training focused on improving his ability to explore internal features of faces, to discriminate specific facial features of familiar and unfamiliar faces, and to provide his family with strategies to use in the future. At the end of the training programme L.G. no longer failed to recognise close and distant relatives and classmates and did not falsely recognise unknown people.

Phasic alertness enhances processing of face and non-face stimuli in congenital prosopagnosia.

Congenital prosopagnosia (CP) is a severe face processing impairment that occurs in the absence of any obvious brain damage and has often been associated with a more general deficit in deriving holistic relations between facial features or even between non-face shape dimensions. Here we further characterized this deficit and examined a potential way to ameliorate it. To this end we manipulated phasic alertness using alerting cues previously shown to modulate attention and enhance global processing of visual stimuli in normal observers. Specifically, we first examined whether individuals with CP, similarly to controls, would show greater global processing when exposed to an alerting cue in the context of a non-facial task (Navon global/local task). We then explored the effect of an alerting cue on face processing (upright/inverted face discrimination). Confirming previous findings, in the absence of alerting cues, controls showed a typical global bias in the Navon task and an inversion effect indexing holistic processing in the upright/inverted task, while CP failed to show these effects. Critically, when alerting cues preceded the experimental trials, both groups showed enhanced global interference and a larger inversion effect. These results suggest that phasic alertness may modulate visual processing and consequently, affect global/holistic perception. Hence, these findings further reinforce the notion that global/holistic processing may serve as a possible mechanism underlying the face processing deficit in CP. Moreover, they imply a possible route for enhancing face processing in individuals with CP and thus shed new light on potential amelioration of this disorder.

Rehabilitation of face-processing skills in an adolescent with prosopagnosia: Evaluation of an online perceptual training programme.

In this paper we describe the case of EM, a female adolescent who acquired prosopagnosia following encephalitis at the age of eight. Initial neuropsychological and eye-movement investigations indicated that EM had profound difficulties in face perception as well as face recognition. EM underwent 14 weeks of perceptual training in an online programme that attempted to improve her ability to make fine-grained discriminations between faces. Following training, EM's face perception skills had improved, and the effect generalised to untrained faces. Eye-movement analyses also indicated that EM spent more time viewing the inner facial features post-training. Examination of EM's face recognition skills revealed an improvement in her recognition of personally-known faces when presented in a laboratory-based test, although the same gains were not noted in her everyday experiences with these faces. In addition, EM did not improve on a test assessing the recognition of newly encoded faces. One month after training, EM had maintained the improvement on the eye-tracking test, and to a lesser extent, her performance on the familiar faces test. This pattern of findings is interpreted as promising evidence that the programme can improve face perception skills, and with some adjustments, may at least partially improve face recognition skills.

Facial affect recognition difficulties in traumatic brain injury rehabilitation services.

PRIMARY OBJECTIVE: The occurrence of facial affect recognition difficulties in a sample of people accessing traumatic brain injury (TBI) rehabilitation services was examined. It was hypothesized that between 13-39% of participants would demonstrate clinically significant impairment in facial affect recognition. RESEARCH DESIGN: Cross-sectional sample of eligible participants who were current clients of eight brain injury services were invited to participate. METHODS AND PROCEDURES: Forty-five participants with mild-to-severe TBI were assessed for facial affect recognition difficulties using the facial affect discrimination, naming, selection and matching sub-tests of the Florida Affect Battery. MAIN OUTCOMES AND RESULTS: Fifty-one per cent of participants had at least moderate difficulties with facial affect recognition. CONCLUSIONS: The current sample was not a random selection from the population of people with TBI, so the results do not establish a formal estimate of prevalence. Nonetheless, the data indicate that when assessing typical clients with severe brain injuries presenting to neurorehabilitation services, there is likely to be a high frequency of occurrence of facial affect recognition difficulties. Rehabilitation outcomes may be improved by screening for and treating facial affect recognition difficulties following TBI. Further examination and development of treatment options is warranted.

Prosopagnosia after stroke: potentials for impairment and treatment.

The ability to recognize and identify people and determine how they may be feeling from looking at their faces is an important skill that people normally achieve effortlessly in infancy. Effective face recognition skills remain essential for social competence throughout the life course. A major cause of impairment in face processing, conventionally known as prosopagnosia, is stroke. In this article, the potentials for acquired prosopagnosia after stroke are examined. The incidence of prosopagnosia after stroke is difficult to establish, but in one clinical sample about half of those who survived a right hemisphere stroke had prosopagnosia. The recently published National Clinical Guideline for Stroke 2012 omits reference to assessment for prosopagnosia, which suggests that the personal distress and negative impact on social life that can accompany prosopagnosia is not fully appreciated or at least not considered a priority after stroke. The few published cases where there has been a focused attempt to provide rehabilitation for chronic prosopagnosia suggest that lesions in face-processing areas are resistant to treatment but that some recovery can accompany extended practice. It is concluded that where there is evidence of prosopagnosia following stroke, treatment should be offered, although rehabilitation may be better focused on supporting and extending existing compensatory strategies, such as the use of voice, body shape, and gait to assist in person recognition and, as an important consequence, social functioning.

Using SenseCam with an amnesic patient: accessing inaccessible everyday memories.

Forgetting is a normal and everyday occurrence that may sometimes reflect a complete loss of the mnemonic record or a failure to encode it in the first place. However, on many occasions with the help of cues we can eventually or suddenly recall a memory that seemed to be lost, thus highlighting the probability that many instances of "forgetting" may in fact reflect inaccessibility rather than true loss. We report here on our amnesic patient CR who presents an extreme example of this normal everyday forgetting. For 4 weeks, CR recorded regular personal autobiographical events both on a SenseCam (henceforth SC) and in a written diary form. Subjective and objective aspects of recall were measured each weekend both without any cues and then with either a SC or diary cue. We show that the SC enabled CR to recall significantly more detailed episodic memories than reading the diary and importantly we observed that the qualitative nature of these memories was different. We comment on the considerable potential of SC for therapeutic purposes.

Enhancement of face recognition learning in patients with brain injury using three cognitive training procedures.

Twenty patients with impairments of face recognition, in the context of a broader pattern of cognitive deficits, were administered three new training procedures derived from contemporary theories of face processing to enhance their learning of new faces: semantic association (being given additional verbal information about the to-be-learned faces); caricaturing (presentation of caricatured versions of the faces during training and veridical versions at recognition testing); and part recognition (focusing patients on distinctive features during the training phase). Using a within-subjects design, each training procedure was applied to a different set of 10 previously unfamiliar faces and entailed six presentations of each face. In a "simple exposure" control procedure (SE), participants were given six presentations of another set of faces using the same basic protocol but with no further elaboration. Order of the four procedures was counterbalanced, and each condition was administered on a different day. A control group of 12 patients with similar levels of face recognition impairment were trained on all four sets of faces under SE conditions. Compared to the SE condition, all three training procedures resulted in more accurate discrimination between the 10 studied faces and 10 distractor faces in a post-training recognition test. This did not reflect any intrinsic lesser memorability of the faces used in the SE condition, as evidenced by the comparable performance across face sets by the control group. At the group level, the three experimental procedures were of similar efficacy, and associated cognitive deficits did not predict which technique would be most beneficial to individual patients; however, there was limited power to detect such associations. Interestingly, a pure prosopagnosic patient who was tested separately showed benefit only from the part recognition technique. Possible mechanisms for the observed effects, and implications for rehabilitation, are discussed.

Behavioral change and its neural correlates in visual agnosia after expertise training.

Agnosia, the impairment in object and face recognition despite intact vision and intelligence, is one of the most intriguing and debilitating neuropsychological deficits. The goal of this study was to determine whether S.M., an individual with longstanding visual agnosia and concomitant prosopagnosia, can be retrained to perform visual object recognition and, if so, what neural substrates mediate this reacquisition. Additionally, of interest is the extent to which training on one type of visual stimulus generalizes to other visual stimuli, as this informs our understanding of the organization of ventral visual cortex. Greebles were chosen as the stimuli for retraining given that, in neurologically normal individuals, these stimuli can engage the fusiform face area. Posttraining, S.M. showed significant improvement in recognizing Greebles, although he did not attain normal levels of performance. He was also able to recognize untrained Greebles and showed improvement in recognizing common objects. Surprisingly, his performance on face recognition, albeit poor initially, was even more impaired following training. A comparison of pre- and postintervention functional neuroimaging data mirrored the behavioral findings: Face-selective voxels in the fusiform gyrus prior to training were no longer so and were, in fact, more Greeble-selective. The findings indicate potential for experience-dependent dynamic reorganization in agnosia with the possibility that residual neural tissue, with limited capacity, will compete for representations.

Effect of training frequency on face-name recall by adults with traumatic brain injury.

Many TBI survivors have difficulty recalling the names of people with whom they frequently interact. Researchers have established that mnemonics and visual imagery strategies are often effective in facilitating encoding and recall of such information; however, no research exists pertaining to the frequency that such training should occur. The purpose of this study was to assess the relative effectiveness of three frequencies of intervention sessions--once per day, two times per week, and five times per day--on TBI survivors' ability to recall face-name associations. Results showed that sessions held daily and twice a week were more effective than sessions held five times per day. Mnemonics and visual imagery strategies were effective for four of the seven participants, regardless of frequency of intervention sessions. Implications for treatment and future research are discussed.