Ruth Brunsdon

Training of familiar face recognition and visual scan paths for faces in a child with congenital prosopagnosia

In the current report we describe a successful training study aimed at improving recognition of a set of familiar face photographs in K., a 4-year-old girl with congenital prosopagnosia (CP). A detailed assessment of K.s face-processing skills showed a deficit in structural encoding, most pronounced in the processing of facial features within the face. In addition, eye movement recordings revealed that K.s scan paths for faces were characterized by a large percentage of fixations directed to areas outside the internal core features (i.e., eyes, nose, and mouth), in particular by poor attendance to the eye region. Following multiple baseline assessments, training focused on teaching K. to reliably recognize a set of familiar face photographs by directing visual attention to specific characteristics of the internal features of each face. The training significantly improved K.s ability to recognize the target faces, with her performance being flawless immediately after training as well as at a follow-up assessment 1 month later. In addition, eye movement recordings following training showed a significant change in K.s scan paths, with a significant increase in the percentage of fixations directed to the internal features, particularly the eye region. Encouragingly, not only was the change in scan paths observed for the set of familiar trained faces, but it generalized to a set of faces that was not presented during training. In addition to documenting significant training effects, our study raises the intriguing question of whether abnormal scan paths for faces may be a common factor underlying face recognition impairments in childhood CP, an issue that has not been explored so far.

Treatment of irregular word spelling in developmental surface dysgraphia.

An increasing number of cognitive neuropsychological treatment studies of acquired dysgraphia have been published in recent years, but to our knowledge there are no corresponding studies of developmental dysgraphia. This paper reports a cognitive neuropsychological treatment programme designed for a child with developmental surface dysgraphia. The treatment aim was to improve functioning of the orthographic output lexicon, and so treatment methods targeted irregular word spelling. Treatment methods were based on previous successful treatments employed in cases of adult acquired surface dysgraphia (Behrmann, 1987; De Partz, Seron, & Van der Linden, 1992; Weekes & Coltheart, 1996). Results showed a significant treatment effect for both spelling and reading of irregular words that was largely stable over time and that generalised partially to spelling of untreated irregular words. Homophone words were not treated but some aspects of homophone reading and spelling also improved, though homophone confusion errors remained. Comparison of treatment effectiveness with and without mnemonics suggested that the mnemonic cue itself was not necessary to achieve treatment success for irregular word spelling. Analyses revealed that untreated irregular words whose spellings became correct as a result of treatment generalisation were those whose original misspellings were closest to being correct prior to treatment. Results also provided preliminary evidence that the mechanism underlying treatment generalisation involved improved access to orthographic representations, resulting in an increased tendency to employ orthography for spelling attempts and reduced reliance on phoneme to grapheme conversion.

Topographical disorientation: Towards an integrated framework for assessment

Topographical disorientation, the inability to find ones way in large-scale environments, is a relatively common disorder. However, there are relatively few cognitive neuropsychological studies that investigate the nature of topographical cognition. Theoretical progress has been hindered by a number of factors including: terminological confusion; lack of theoretically driven assessment; the use of broad classifications for the nature of underlying impairments; and an ongoing failure to examine topographical skills in real-life settings. As a result, there is currently no well-established or widely accepted theoretical framework encompassing all aspects of this multifaceted area of cognition. In addition, there is a relative paucity of published case studies that include a comprehensive, theoretically based assessment of topographical disorientation, and treatment of the disorder has received virtually no formal investigation (with the exception of Davis & Coltheart, 1999). Thus, the current paper focuses on the development of a broad framework for understanding topographical cognition that integrates a number of recent theories of topographical orientation and mental imagery (Farah, 1984; Kosslyn, 1980; Riddoch & Humphreys, 1989). The aim of the paper is to present a preliminary framework that can be used as a basis for further refinement and development of theoretical proposals, and be employed by clinicians as a starting point for assessment planning.

Treatment of lexical processing in mixed dyslexia: A case study

In the field of dyslexia, cognitive neuropsychological models provide a useful framework for detailed analyses of an individuals reading performance. However, the application of this work to remediation, especially in children, remains relatively unexplored. This study evaluates a lexical treatment programme that has been used successfully in cases of adult acquired surface dyslexia (e.g., Coltheart & Byng, 1989; Weekes & Coltheart, 1986) in the context of severe mixed developmental dyslexia. The results indicate a significant treatment effect that is stable over time and that generalises to untreated words, to spelling, and to some aspects of sublexical processing. Questions related to the use of adult models and methods for developmental conditions and the usefulness of such models in cases of severe mixed dyslexia are discussed. Issues related to treatment generalisation are also explored, with consideration of generalisation of lexical training to sublexical processes, improvement in reading of untreated words, and the effect of reading interventions on spelling performance.

Developmental prosopagnosia : A case analysis and treatment study

This paper reports a treatment case study focused on face perception impairments designed for AL, an 8-year-old child with prosopagnosia. ALs prosopagnosia was characterized by deficits at the level of structural encoding—that is, he was unable to achieve normal basic perception of faces. This impairment then impacted on all subsequent aspects of familiar- and unfamiliar-face processing. Detailed assessment of feature processing revealed impairments in perception of facial features with a dissociation between relatively good perception of the mouth feature and poor perception of eye and nose features. Interestingly, results also suggested at least partial internal representation of facial features despite long-standing deficits in perception of these features. A treatment programme focused on training in perception, and analysis of facial features and familiar-face naming was conducted. Treatment resulted in excellent face naming for familiar faces, a decreased reliance on nonfacial cues and a reduction in ALs tendency to misidentify unfamiliar faces as family members.

Severe developmental letter-processing impairment: A treatment case study

We report the case of ET, a 7-year-old child with a severe developmental letter-processing impairment. Detailed assessment revealed multiple impairments of the letter-processing system affecting abstract visual letter representation, semantics, and connections between the phonological processing modules and the orthographic buffer. Treatment methods focused on letter sounding through development of abstract visual representation and semantic representation of letters. Treatment resulted in dramatic and enduring improvements in cross-case matching, letter/number categorization, and letter sounding. Cognitive neuropsychological reading research has largely focused on word processing, with a relative neglect of single-letter processing. The current study investigated letter processing in greater detail than has been usual and outlines a broad theoretical framework for letter processing. ETs assessment and treatment data are used to support and question predictions from the framework. A number of theoretical implications are discussed with reference to ETs data and that of other reported cases of impaired single-letter processing. Finally, the paucity of investigation of letter processing in children is highlighted, particularly with regard to integrity of abstract letter representation in developmental dyslexia.

Successful treatment of sublexical reading deficits in a child with dyslexia of the mixed type

The application of cognitive neuropsychological theories to the design and implementation of treatment programmes remains relatively unexplored, especially in children. In addition, cognitive neuropsychological treatment programmes for dyslexia to date have focused on specific dyslexias such as phonological and surface dyslexia and have ignored the large subgroup of children with severe and multiple impairments of the reading system, those with mixed dyslexia. This study evaluates a sublexical treatment programme designed for a child with dyslexia of the mixed type. The treatment approach is based on sublexical treatment programmes that have been reported in cases of adult acquired dyslexia (Berndt & Mitchum, 1994; De Partz, 1986; Nickels, 1992). The focus of treatment is on nonword reading and includes training in grapheme parsing, grapheme-to-phoneme knowledge, and phoneme blending. Treatment outcome is measured through extensive pre- and post-treatment assessment of sublexical and lexical processing, semantics, and general phonology. The treatment design enables an objective assessment of treatment efficacy, stability of treatment effects over time and generalisability of the treatment to untreated stimuli and related language processes. The study illustrates the validity of the use of models and methods derived from work with adults with acquired impairments to paediatrics, and the usefulness of analytical models in cases of severe mixed dyslexia.

Visual agnosia and prosopagnosia in childhood: a prospective case study.

Selective impairments in visual processing are well documented in adults but rarely reported in children. The few childhood cases reported are mostly retrospective accounts with little attention paid to developmental, assessment or management issues. We report a prospective case study of a boy with prosopagnosia and visual processing deficits of presumed developmental origin. At the age of 4 years, AL presented with a range of cognitive and visual recognition deficits. Subsequent assessments revealed an evolving pattern in visual recognition and dissociations between developing skills. At the age of 7 AL has impairments in early perceptual analysis, visual organisation and in complex visual processing. Although he can identify facial features and match faces he is unable to recognise familiar faces. His reading and spelling are developing normally. The nature of his deficits and his progress are discussed within a cognitive neuropsychological framework.

Idiopathic macrocephaly in the infant: long-term neurological and neuropsychological outcome

RationaleThe long-term outcome of idiopathic macrocephaly is presently unknown.Methods and resultsIn the current study (n=15), MRI conducted at long-term review showed regression of orbito-frontal extradural collections and normal or slightly enlarged ventricular space compared to infant examination. Head circumference had normalised in all but one participant. Neuropsychological assessments of nine participants showed general intellectual ability within the normal range in the majority of participants; however, specific deficits in attention were evident. Clinical interviews conducted with a smaller sub-group revealed anecdotal histories of behavioural difficulties and reading or arithmetic difficulties in half of the total sample.ConclusionsProspective review studies such as this indicate that abnormal radiological findings in infancy are not necessarily predictive of neurodevelopmental problems and may reflect a normal variant. However, while overall intellectual ability may be within average limits in this diagnostic sample, considerable individual variations remain in specific areas of neuropsychological function.

Predicting generalization in the training of irregular-word spelling: Treating lexical spelling deficits in a child

This paper presents a single case study investigating the mechanisms underlying generalization of treatment benefits to untrained words in spelling. Brunsdon, Coltheart, and Nickels (2005) observed that untreated words that improved tended to be those whose errors were closest to being correct prior to treatment. These words also tended to be high in written frequency. The present study employed the same treatment techniques as those used by Brunsdon et al. with K.M., a developmental surface dysgraphic. During a first treatment the characteristics of words whose spelling improved without specific training were identified. These characteristics were then used in a second treatment to test whether it was possible to predict generalization. The results showed that treatment generalization to untreated irregular words was best predicted by neighbourhood size and frequency. We suggest that the processes underlying treatment generalization are based on the interaction between the orthographic lexicon and the graphemic buffer. Clinical implications are discussed.