Attention and other cognitive deficits in aphasia: presence and relation to language and communication measures.
ABSTRACT This study was designed to further elucidate the relationship between cognition and aphasia, with a focus on attention. It was hypothesized that individuals with aphasia would display variable deficit patterns on tests of attention and other cognitive functions and that their attention deficits, particularly those of complex attention functions, would be related to their language and communication status.
A group of individuals with varying types and severity of aphasia and a group of age- and education-matched adults with no brain damage completed tests of attention, short-term and working memory, and executive functioning.
Overall, the group with aphasia performed significantly more poorly than the control group on the cognitive measures but displayed variability in the presence, types, and severity of their attention and other cognitive deficits. Correlational and regression analyses yielded significant relations between participants' attention deficits and their language and communication status.
The findings accorded well with prior research identifying (a) attention and other cognitive deficits in most but not all individuals with aphasia; (b) heterogeneity in the types and severity of attention and other cognitive symptoms among individuals with cognitive impairments; and (c) potent associations among attention, language, and other cognitive domains. Implications for clinical practice and future research are discussed.
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ABSTRACT: A number of studies have identified impairments in one or more types/aspects of attention processing in patients with aphasia (PWA) relative to healthy controls; person-to-person variability in performance on attention tasks within the PWA group has also been noted. Studies using non-linguistic stimuli have found evidence that attention is impaired in this population even in the absence of language processing. An underlying impairment in non-linguistic, or domain-general, attention processing could have implications for the ability of PWA to attend during therapy sessions, which in turn could impact long-term treatment outcomes. With this in mind, this study aimed to systematically examine the effect of task complexity on reaction time (RT) during a non-linguistic attention task, in both PWA and controls. Additional goals were to assess the effect of task complexity on between-session intra-individual variability (BS-IIV) in RT and to examine inter-individual differences in BS-IIV. Eighteen PWA and five age-matched neurologically healthy controls each completed a novel computerized non-linguistic attention task measuring five types of attention on each of four different non-consecutive days. A significant effect of task complexity on both RT and BS-IIV in RT was found for the PWA group, whereas the control group showed a significant effect of task complexity on RT but not on BS-IIV in RT. Finally, in addition to these group-level findings, it was noted that different patients exhibited different patterns of BS-IIV, indicating the existence of inter-individual variability in BS-IIV within the PWA group. Results may have implications for session-to-session fluctuations in attention during language testing and therapy for PWA.Neuropsychologia 11/2014; · 3.45 Impact Factor
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ABSTRACT: Objectives The purpose of this paper is review of research on the co-occurrence of executive dysfunction in patients with aphasia after stroke. Review Aphasic speech disorders and cognitive dysfunctions are frequent consequences of the irregularities in the blood flow within the brain. Aphasia, apart from language deficits, may be accompanied by non-linguistic cognitive disorders. More and more often the co-existence of speech disorders of aphasia and the disorders of executive functions are considered. The role of executive functions is connected with the processes of planning, creating strategies, monitoring actions, self-regulation, and integration of various cognitive modalities. These activities are undoubtedly coupled with the process of speech generation. Therefore, the effective communication depends on the integrity of executive functions. Conclusions In the present paper the author has presented a survey of researches on the executive functions disorders and aphasia after stroke. In the researches the author has evaluated the level of executive functions with the application of neuropsychological methods as well as compared those results in terms of various aspects of verbal functioning, capability to communicate and conducting conversations among people with aphasia. In addition, as studies argue, the efficiency of executive functions has a significant impact on the effectiveness of aphasia rehabilitation.Postępy Psychiatrii i Neurologii. 03/2014; 23(1):41–46.
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ABSTRACT: The estimated prevalence of aphasia in the UK and the USA is 250 000 and 1 000 000, respectively. The commonest aetiology is stroke. The impairment may improve with behavioural therapy, and trials using cortical stimulation or pharmacotherapy are undergoing proof-of-principle investigation, but with mixed results. Aphasia is a heterogeneous syndrome, and the simple classifications according to the Broca-Wernicke-Lichtheim model inadequately describe the diverse communication difficulties with which patients may present. Greater knowledge of how intact neural networks promote recovery after aphasic stroke, either spontaneously or in response to interventions, will result in clearer hypotheses about how to improve the treatment of aphasia. Twenty-five years ago, a pioneering study on healthy participants heralded the introduction of functional neuroimaging to the study of mechanisms of recovery from aphasia. Over the ensuing decades, such studies have been interpreted as supporting one of three hypotheses, which are not mutually exclusive. The first two predate the introduction of functional neuroimaging: that recovery is the consequence of the reconstitution of domain-specific language systems in tissue around the lesion (the 'perilesional' hypothesis), or by homotopic cortex in the contralateral hemisphere (the 'laterality-shift' hypothesis). The third is that loss of transcallosal inhibition to contralateral homotopic cortex hinders recovery (the 'disinhibition' hypothesis). These different hypotheses at times give conflicting views about rehabilitative intervention; for example, should one attempt to activate or inhibit a contralateral homotopic region with cortical stimulation techniques to promote recovery? This review proposes that although the functional imaging data are statistically valid in most cases, their interpretation has often favoured one explanation while ignoring plausible alternatives. In our view, this is particularly evident when recovery is attributed to activity in 'language networks' occupying sites not observed in healthy participants. In this review we will argue that much of the distribution of what has often been interpreted as language-specific activity, particularly in midline and contralateral cortical regions, is an upregulation of activity in intact domain-general systems for cognitive control and attention, responding in a task-dependent manner to the increased 'effort' when damaged downstream domain-specific language networks are impaired. We further propose that it is an inability fully to activate these systems that may result in sub optimal recovery in some patients. Interpretation of the data in terms of activity in domain-general networks affords insights into novel approaches to rehabilitation.Brain 06/2014; · 10.23 Impact Factor