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The use of data from people with cognitive impairments to inform theories of cognition is an established methodology, particularly in the field of cognitive neuropsychology. However, it is less well known that studies that aim to improve... more
The use of data from people with cognitive impairments to inform theories of cognition is an established methodology, particularly in the field of cognitive neuropsychology. However, it is less well known that studies that aim to improve cognitive functioning using treatment can also inform our understanding of cognition. This paper discusses a range of challenges that researchers face when testing theories of cognition and particularly when using treatment as a tool for doing so. It highlights the strengths of treatment methodology for testing causal relations and additionally discusses how generalization of treatment effects can shed light on the nature of cognitive representations and processes. These points are illustrated using examples from the Special Issue of Cognitive Neuropsychology entitled Treatment as a tool for investigating cognition.
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Page 1. Story writing skills of adults with a history language-impairment Karen M. Smith-Lock Æ Lyndsey Nickels Æ Lynne Mortensen Published online: 10 September 2008 Ó Springer Science+Business Media BV 2008 Abstract ...
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This paper informs our understanding of the representation and processing of mass and count nouns through an investigation of the underlying causes of mass/count specific impairments in in two people with aphasia, DEH and GEC. The factors... more
This paper informs our understanding of the representation and processing of mass and count nouns through an investigation of the underlying causes of mass/count specific impairments in in two people with aphasia, DEH and GEC. The factors influencing the production of mass and count nouns and noun phrases was comprehensively assessed. The results showed that GEC's impairment affected mass noun naming, resulting in the production of semantic paraphasias and no responses. In contrast, DEH frequently substituted mass determiners with count determiners leading to ungrammatical noun phrases. In comparison to younger control group, a control group of older adults showed similar difficulties to DEH with mass noun phrases, although less severe, indicating effects of cognitive ageing on lexical and semantic processing. DEH and the elderly controls' results replicate and support previous findings regarding the lexical-syntactic representation of mass/count information. GEC's difficulties extend these findings by providing additional evidence for a semantic component in the representation of countability (e.g., a semantic feature/concept COUNTABLE for count nouns, UNCOUNTABLE for mass nouns) which contributes to mass and count noun selection. GEC's mass noun difficulties are suggested to result from weaker connection strength between noun lemmas and mass concepts compared to count concepts as a result of the overall lower frequency distribution of mass nouns.
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In healthy controls, picture naming performance can be facilitated by a single prior exposure to the same picture... more
In healthy controls, picture naming performance can be facilitated by a single prior exposure to the same picture ("priming"). This priming phenomenon is utilized in the treatment of aphasia, which often includes repeated picture naming as part of a therapeutic task. The current study sought to determine whether single and/or multiple exposures facilitate subsequent naming in aphasia and whether such facilitatory effects act through normal priming mechanisms. A functional magnetic resonance imaging paradigm was employed to explore the beneficial effects of attempted naming in two individuals with aphasia and a control group. The timing and number of prior exposures was manipulated, with investigation of both short-term effects (single prior exposure over a period of minutes) and long-term effects (multiple presentations over a period of days). Following attempted naming, both short-term and long-term facilitated items showed improvement for controls, while only the long-term condition showed benefits at a behavioral level for the participants with aphasia. At a neural level, effects of long-term facilitation were noted in the left precuneus for one participant with aphasia, a result also identified for the equivalent contrast in controls. It appears that multiple attempts are required to improve naming performance in the presence of anomia and that for some individuals with aphasia the source of facilitation may be similar to unimpaired mechanisms engaged outside the language network.
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Topographical disorientation, the inability to find one's way in large-scale environments, is a relatively common... more
Topographical disorientation, the inability to find one's 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.
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... (1991a), it remains to be demonstrated that, using the same parameters, their model could alsosimulate the patterns ... EVALUATING MODELS OF SPOKEN WORD RECOGNITION ... IAA models) will spread to affect the network as a whole as... more
... (1991a), it remains to be demonstrated that, using the same parameters, their model could alsosimulate the patterns ... EVALUATING MODELS OF SPOKEN WORD RECOGNITION ... IAA models) will spread to affect the network as a whole as activation reverberates between levels. ...
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In this paper we investigate whether homophones have shared (eg, Dell, 1990; Levelt, Roelofs, & Meyer, 1999) or independent (eg, Caramazza, Costa, Miozzo, & Bi, 2001) phonological representations.... more
In this paper we investigate whether homophones have shared (eg, Dell, 1990; Levelt, Roelofs, & Meyer, 1999) or independent (eg, Caramazza, Costa, Miozzo, & Bi, 2001) phonological representations. We carried out a homophone reading aloud task with low ...
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This paper presents a treatment study with a developmental dysgraphic girl, KM, and addresses the mechanisms by which orthographic learning of spelling rules might occur. Before treatment, KM's spelling of words and nonwords was... more
This paper presents a treatment study with a developmental dysgraphic girl, KM, and addresses the mechanisms by which orthographic learning of spelling rules might occur. Before treatment, KM's spelling of words and nonwords was impaired. Analyses of spelling errors ...
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In the last decade, an increasing number of single case studies that use a cognitive neuropsychological approach to the remediation of developmental dyslexia (ie reading disorders) and dysgraphia (ie spelling disorders) have been... more
In the last decade, an increasing number of single case studies that use a cognitive neuropsychological approach to the remediation of developmental dyslexia (ie reading disorders) and dysgraphia (ie spelling disorders) have been published (eg Broom & Doctor, 1995; Brunsdon, ...
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Research Interests: Psychology, Cognitive Science, Information Retrieval, Phonology, Phonetics, and 28 moreSemantics, Methodology, Psycholinguistics, Vocabulary, Theory, English, Syntax, Attention, Linguistics, Language, Language Production, German, Memory, Humans, Models, Psycholinguistic, Grammar, Concept Formation, Female, Male, Nouns, Noun, Awareness, Experiments, Adult, Network Model, Experimental Data, and Verbal Learning
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Research Interests: Psychology, Cognitive Science, Experimental Psychology, Decision Making, Phonetics, and 29 moreSemantics, Cognition, Vocabulary, English, Australia, Reading, Face recognition (Psychology), Language, Word Learning, Orthography, Learning, Humans, Child, Teaching Methods, Word Recognition, Female, Male, Child Psychology, Word, Context Effect, Task analysis, Experiments, Analysis of Variance, Vocabulary development, Task Performance and Analysis, Child Language, Choice Behavior, Nino, and Contextual Information
This paper examines four recent therapy studies, two involving deep dyslexic patients and two involving surface dyslexic patients. These studies illustrate that remediation of aspects of acquired dyslexia can have positive benefits for... more
This paper examines four recent therapy studies, two involving deep dyslexic patients and two involving surface dyslexic patients. These studies illustrate that remediation of aspects of acquired dyslexia can have positive benefits for the patients concerned which often extend beyond an improvement in reading aloud. It is argued that, although it may not be immediately apparent, the remediation of acquired reading impairments (and even of reading aloud) can be of functional significance for an aphasic subject.
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This paper describes the replication of a therapeutic programme originally used by one of the authors, Byng (Cognitive Neuropsychology, 1988, 5, 629-676) to remediate a specific sentence processing deficit. Our patient is shown to have... more
This paper describes the replication of a therapeutic programme originally used by one of the authors, Byng (Cognitive Neuropsychology, 1988, 5, 629-676) to remediate a specific sentence processing deficit. Our patient is shown to have similar although not identical deficits to those of one of the patients (JG) described in that programme. Sentence comprehension and production both improved as a result of therapy. The pattern of results observed gave further insights into both the nature of the patient's deficit and the mechanism of therapy.
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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,... more
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. ET's assessment and treatment data are used to support and question predictions from the framework. A number of theoretical implications are discussed with reference to ET's 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.
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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... more
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.
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A central focus in remedial teaching is the generalisation of responses to contexts in which a student has never been explicitly instructed. Remarkably little is known about how and when generalisation occurs. In this article we examine... more
A central focus in remedial teaching is the generalisation of responses to contexts in which a student has never been explicitly instructed. Remarkably little is known about how and when generalisation occurs. In this article we examine general-isation effects in the context of ...
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This study was designed to replicate and extend an earlier study in which a therapy programme was carried out with two agrammatic aphasic patients with sentence processing impairments suggested to be at the level of mapping thematic roles... more
This study was designed to replicate and extend an earlier study in which a therapy programme was carried out with two agrammatic aphasic patients with sentence processing impairments suggested to be at the level of mapping thematic roles and grammatical relations (Byng 1988). In the current study one of the therapy procedures implemented in the previous study was repeated with
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Background: Recurrent perseverative errors involve either the complete or partial repetition of a prior response to a new stimulus. They are commonly produced by speakers with aphasia and are difficult to remediate.During the preparation... more
Background: Recurrent perseverative errors involve either the complete or partial repetition of a prior response to a new stimulus. They are commonly produced by speakers with aphasia and are difficult to remediate.During the preparation of this paper, Dr Lyndsey Nickels was funded by an Australian Research Council QE2 Fellowship.Aims: This paper reviews research on recurrent perseverative errors with a focus
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Background: Recurrent perseverative errors are most commonly produced by speakers with aphasia (Albert & Sandson, 1986). While some research has proposed that recurrent perseverative... more
Background: Recurrent perseverative errors are most commonly produced by speakers with aphasia (Albert & Sandson, 1986). While some research has proposed that recurrent perseverative errors are primarily caused by an impaired ability to inhibit a prior response, most recent research proposes that these errors occur as a direct result of underlying language impairment at any specified processing level (e.g., Cohen
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Background: Both orthographic and phonological information from the target word can be appropriate cues in anomia treatment. Furthermore, both types of cues are used very frequently in clinical practice, although their underlying... more
Background: Both orthographic and phonological information from the target word can be appropriate cues in anomia treatment. Furthermore, both types of cues are used very frequently in clinical practice, although their underlying mechanisms of effectiveness and stability are still a matter of debate (e.g., Basso, Marangolo, Piras, & Galluzzi, 2001; Best, Herbert, Hickin, Osborne, & Howard, 2002; Howard & Harding,
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Background: While previous research has shown that a number of tasks can be successful in improving word retrieval following aphasia, the majority of studies result in improvement restricted to treated items. This has two major... more
Background: While previous research has shown that a number of tasks can be successful in improving word retrieval following aphasia, the majority of studies result in improvement restricted to treated items. This has two major implications: first it is essential that personally relevant items of communicative value are treated. Second, treatment is likely to be required long term. Therapy provided
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In the treatment of word finding in anomia both 'phonological' tasks (e.g. repetition, phonemic cueing), and... more
In the treatment of word finding in anomia both 'phonological' tasks (e.g. repetition, phonemic cueing), and 'semantic' tasks (e.g. word-picture matching, semantic judgements) have been found to be effective. However, there have been few direct comparisons of the relative effectiveness of these tasks within the same individuals: most reports differ in both tasks and participants. Hence it is difficult to
This paper focuses on the role of treatment in cognitive neuropsychological research, arguing that treatment for cognitive impairments should be viewed as a powerful methodology for developing, evaluating, and extending cognitive... more
This paper focuses on the role of treatment in cognitive neuropsychological research, arguing that treatment for cognitive impairments should be viewed as a powerful methodology for developing, evaluating, and extending cognitive theories. We suggest that the key aim of cognitive neuropsychology should be characterized as the use of data from the investigation and treatment of individuals with cognitive disorders to develop, evaluate, and extend theories of normal cognition. To support this assertion, this paper discusses examples of how treatment studies have informed theory. The major methodological tool is generalization logic, both generalization across items and generalization across tasks. However, an alternative is to use case series methodology to test predicted correlations between particular cognitive skills and response to treatment. These methods enable explicit testing of a theory or discrimination between theories, focusing on the nature of cognitive representations, the architecture of the cognitive system, and the acquisition of cognitive skills.