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

Abstract

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 generalized 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 laboratorybased 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.Keywords: Prosopagnosia, face recognition, rehabilitation, training, encephalitis. Rehabilitation of Prosopagnosia 3Rehabilitation of Face-Processing Skills in an Adolescent with Prosopagnosia:Evaluation of an Online Perceptual Training Programme Prosopagnosia is a cognitive condition characterised by a relatively selective deficit in face recognition. Traditionally, the disorder has been described in a small number of individuals who acquire face recognition difficulties following neurological injury or illness, typically affecting occipitotemporal regions (de Renzi, Perani, Carlesimo, Silveri, & Fazio, 1994;Gainotti & Marra, 2011). Although acquired prosopagnosia in its purest form is a rare condition (Gloning, Gloning, & Hoff, 1967;Zihl & von Cramon, 1986), many more individuals with brain damage are believed to experience moderate-to-severe face-processing deficits alongside other cognitive impairments (Hécaen & Angelergues, 1962;Valentine, Powell, Davidoff, Letson, & Greenwood, 2006). Further, as many as 2.9% (Bowles et al., 2009) of the population may experience a developmental form of the disorder (e.g. Bate & Cook, 2012;Duchaine & Nakayama, 2005). Hence, exploration of the remediation of prosopagnosia is an urgent clinical issue that, unfortunately, has received little attention to date.However, this issue is complicated by findings that prosopagnosia is a heterogeneous condition that not only differs in severity (e.g. Valentine et al., 2006), but also presents with a variable pattern of cognitive symptoms (Barton, 2008;Dalrymple et al., 2011;Le Grand et al., 2006;Susilo & Duchaine, 2013). For instance, individuals with acquired prosopagnosia can sometimes present with deficits...

The neuropsychological rehabilitation of visual agnosia and Balint’s syndrome

“…The additional eight articles appeared to be in line with the outcome of the literature reviews, especially with regard to transferring the training to real-life face recognition (Bate et al, 2015). The study by Davies- Thompson et al (2017) describes a promising restorative approach, however training is very intense and does not improve real-life facial recognition in all participants involved.…”

Guess who? Facial identity discrimination training improves face memory in typically developing children.

“…Davies-Thompson et al (2017) reported an average ~10% improvement in CFMT scores in 10 adults with acquired prosopagnosia, but this was not significant in a group-level analysis. Although CFMT gains were not available in the studies reported by colleagues (2007, 2014), Bate et al (2015) did not detect an improvement on this test for their adolescent case with acquired prosopagnosia. Whether the larger gains reported here result from the training strategy itself (i.e.…”

“…Twelve manipulated images were then created from each base image, using different combinations of four adjustments (see Figure 2A and 2B): two affecting the spacing of facial features (the distance between the eyes, or the distance between the eyes and mouth), and two affected the size of specific facial features (the eyes and nose). These manipulations were taken from the design of existing training programmes that have experienced at least some success: expression was manipulated by Davies-Thompson et al (2017), spacing by DeGutis et al (2007DeGutis et al ( , 2014, and FACIAL IDENTITY TRAINING 11 feature size by Bate et al (2015). Together, a total of 24 new character images were created for each of the male and female insert cards.…”

Self-ratings of face recognition ability are influenced by gender but not prosopagnosia severity.

“…The last 20 years has seen an abundance of interest in individuals with developmental prosopagnosia (DP), with increasing numbers of adults and children self-referring for clinical screening and/or research participation (e.g. Bate & Bennetts, 2015;Bennetts, Murray, Boyce & Bate, 2017;Bowles et al, 2009;Dalrymple & Palermo, 2015;Geskin & Behrmann, 2017).…”