1/74. "What" and "how": evidence for the dissociation of object knowledge and mechanical problem-solving skills in the human brain.patients with profound semantic deterioration resulting from temporal lobe atrophy have been reported to use many real objects appropriately. Does this preserved ability reflect (i) a separate component of the conceptual knowledge system ("action semantics") or (ii) the operation of a system that is independent of conceptual knowledge of specific objects, and rather is responsible for general mechanical problem-solving skills, triggered by object affordances? We contrast the performance of three patients-two with semantic dementia and focal temporal lobe atrophy and the third with corticobasal degeneration and biparietal atrophy-on tests of real object identification and usage, picture-based tests of functional semantic knowledge, and a task requiring selection and use of novel tools. The patient with corticobasal degeneration showed poor novel tool selection and impaired use of real objects, despite near normal semantic knowledge of the same objects' functions. The patients with semantic dementia had the expected deficit in object identification and functional semantics, but achieved flawless and effortless performance on the novel tool task. Their attempts to use this same mechanical problem-solving ability to deduce (sometimes successfully but often incorrectly) the use of the real objects provide no support for the hypothesis of a separate action-semantic system. Although the temporal lobe system clearly is necessary to identify "what" an object is, we suggest that sensory inputs to a parietal "how" system can trigger the use of objects without reference to object-specific conceptual knowledge.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
2/74. Making requests: illustrations of how right-hemisphere brain damage can affect discourse production.This article examines several factors that influence the production of requests for behavior. Using a role-play methodology, we elicited request productions from well-recovered patients with right-hemisphere brain damage (RHD) and from non brain-damaged control participants. The stimulus items represented variation both on interpersonal factors based on characteristics of the people in the interaction and on situational factors based on what was being requested. A large corpus of responses was elicited from each patient. Responses were coded for request directness, amount of explanatory material over and above the request proper (a relatively demanding method for manipulating the tone of a request), and use of "please" (a relatively simple device for signaling a request). Case-by-case analysis of the patients' performances revealed some common areas of abnormality and also some idiosyncratic features. Some patients produced less explanatory supportive material than control participants, and they tended not to vary the amount of explanatory material as a function of the request scenario. Of interest is that some of the same patients overused "please," and varied their use of this simple device as a function of request scenarios. The discourse strategies observed were likely due to deficits both in pragmatic awareness and in planning utterances. One implication of these results concerns an apt description of the abnormal discourse of RHD patients. The relative lack of supportive explanatory material in their requests may result in patients' seeming rude or inappropriate.- - - - - - - - - - ranking = 1.5keywords = brain (Clic here for more details about this article) |
3/74. 'Speaking in tongues'. Paradoxical fixation on a non-native language following anaesthesia.An intriguing case of transient language disturbance following anaesthesia is described which may throw some light on the way languages are stored in the brain. A review of the existing literature and its relevance to this unique case is discussed.- - - - - - - - - - ranking = 0.25keywords = brain (Clic here for more details about this article) |
4/74. Spoken language correlates of reading impairments acquired in childhood.This study reports the reading difficulties of five children following unilateral left hemisphere stroke sustained either before or during the early stages of literacy acquisition. Although each of the children experienced a period of disturbed language processing in the initial stages postonset, at the time of testing none of the children were considered to be clinically aphasic. Yet, on a standardized test of oral reading each of the children achieved a reading age that lagged behind chronological age and marked reading impairments were disclosed in four of the five children. A set of standardized and nonstandardized tests, aimed at measuring aspects of cognitive and spoken language processing that are considered to be important for normal reading acquisition, was administered. Where nonstandardized tests were used, performance of each of the stroke children was compared to that of groups of normally developing control children, closely matched for chronological age. A range of residual deficits in cognitive and spoken language processing was disclosed among the five brain-damaged children that appeared to be associated with their reading impairments. Two children had expectedly poor reading due to a selective impairment in verbal IQ; a specific phonological reading disorder was revealed in two children, each of which had a residual impairment to phonological awareness; and delayed reading acquisition was observed in one child with a general language deficit. It is suggested that when a child suffers damage to the left hemisphere in the early stages of reading acquisition, difficulties with learning to read are likely to ensue and may arise as a consequence of an underlying cognitive or linguistic deficit.- - - - - - - - - - ranking = 0.25keywords = brain (Clic here for more details about this article) |
5/74. Auditory neuropathy: case study with hyperbilirubinemia.Auditory neuropathy (AN) has been described in the literature as presenting with a combination of audiometric findings that include elevated behavioral audiometric thresholds, auditory brainstem response findings that are not consistent with audiometric findings, poor speech recognition, and present otoacoustic emissions (OAEs) and/or cochlear microphonics. Since the availability of clinical OAE testing, AN has come to be identified with increasing frequency; however, incidence and prevalence figures are unavailable. There is a great deal of discussion about the accurate diagnosis of AN, its characteristics, and its treatment. Some of this discussion is occurring on the internet and over the telephones. The need to continue to provide information in accessible peer-reviewed journals is paramount. Following a review of the literature, a case study is presented of a boy who was diagnosed with AN as a newborn. He experienced hyperbilirubinemia and other neonatal health complications. His educational intervention was managed elsewhere until recently. Information is presented about the progression of the case over a 5-year period that includes audiologic data and communication development results.- - - - - - - - - - ranking = 0.25keywords = brain (Clic here for more details about this article) |
6/74. language and calculation within the parietal lobe: a combined cognitive, anatomical and fMRI study.We report the case of a patient (ATH) who suffered from aphasia, deep dyslexia, and acalculia, following a lesion in her left perisylvian area. She showed a severe impairment in all tasks involving numbers in a verbal format, such as reading aloud, writing to dictation, or responding verbally to questions of numerical knowledge. In contrast, her ability to manipulate non-verbal representations of numbers, i.e., Arabic numerals and quantities, was comparatively well preserved, as evidenced for instance in number comparison or number bisection tasks. This dissociated impairment of verbal and non-verbal numerical abilities entailed a differential impairment of the four arithmetic operations. ATH performed much better with subtraction and addition, that can be solved on the basis of quantity manipulation, than with multiplication and division problems, that are commonly solved by retrieving stored verbal sequences. The brain lesion affected the classical language areas, but spared a subset of the left inferior parietal lobule that was active during calculation tasks, as demonstrated with functional MRI. Finally, the relative preservation of subtraction versus multiplication may be related to the fact that subtraction activated the intact right parietal lobe, while multiplication activated predominantly left-sided areas.- - - - - - - - - - ranking = 0.25keywords = brain (Clic here for more details about this article) |
7/74. The application of cognitive event-related brain potentials (ERPs) in language-impaired individuals: review and case studies.There is a substantial body of basic research that has utilized ERPs to investigate the neurological basis of cognition. This research has, in turn, led to the development of practical applications of cognitive ERPs in patient populations. In particular, recent work has focused on the development of ERP-based assessment measures for the neuropsychological assessment of dyslexia and language impairments secondary to stroke. This review describes the innovative assessment methods program (IAMP), an initiative to utilize ERPs for a neuropsychological assessment of patients who cannot be evaluated by traditional methods. The success of this program has demonstrated that ERPs can be used to reliably evaluate an individual's reading and speech comprehension abilities, independent of behavioral and speech production impediments. In contrast to traditional neuropsychological assessment, these ERP methods can discern the cognitive strategies used by an individual to perform a task.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
8/74. speech recognition training for enhancing written language generation by a traumatic brain injury survivor.Impairments in motor functioning, language processing, and cognitive status may impact the written language performance of traumatic brain injury (TBI) survivors. One strategy to minimize the impact of these impairments is to use a speech recognition system. The purpose of this study was to explore the effect of mild dysarthria and mild cognitive-communication deficits secondary to TBI on a 19-year-old survivor's mastery and use of such a system-specifically, Dragon Naturally Speaking. Data included the % of the participant's words accurately perceived by the system over time, the participant's accuracy over time in using commands for navigation and error correction, and quantitative and qualitative changes in the participant's written texts generated with and without the use of the speech recognition system. Results showed that Dragon NaturallySpeaking was approximately 80% accurate in perceiving words spoken by the participant, and the participant quickly and easily mastered all navigation and error correction commands presented. Quantitatively, the participant produced a greater amount of text using traditional word processing and a standard keyboard than using the speech recognition system. Minimal qualitative differences appeared between writing samples. Discussion of factors that may have contributed to the obtained results and that may affect the generalization of the findings to other TBI survivors is provided.- - - - - - - - - - ranking = 226.92146970375keywords = traumatic brain injury, brain injury, traumatic brain, brain, injury (Clic here for more details about this article) |
9/74. Subcortical brain mechanisms in speech and language.This paper reviews current research and contemporary theories of subcortical participation in the motor control of speech production and language processing. As a necessary precursor to the discussion of the functional roles of the basal ganglia and thalamus, the neuroanatomy of the basal ganglial-thalamocortical circuitry is described. Contemporary models of hypokinetic and hyperkinetic movement disorders based on recent neuroanatomical descriptions of the multi-segmented circuits that characterise basal ganglion anatomy are described. Reported effects of surgically induced lesions in the globus pallidus and thalamus on speech production are reviewed. In addition, contemporary models proposed to explain the possible contribution of various subcortical structures to language processing are described and discussed in the context of evidence gained from observation of the effects of circumscribed surgically induced lesions in the basal ganglia and thalamus on language function. The potential of studies based on examination of the speech/language outcomes of patients undergoing pallidotomy and thalamotomy to further inform the debate relating to the role of subcortical structures in speech motor control and language processing is highlighted.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
10/74. Development of the pediatric test of brain injury.OBJECTIVE: The Pediatric Test of Traumatic brain Injury (PTBI) (currently in its research edition) is a tool for assessing the cognitive-linguistic skills of school-aged children and adolescents in acute care and rehabilitation settings after traumatic brain injury. Development of the PTBI was motivated by the fact that, to date, no standardized test has been available to assess the full range of cognitive-linguistic impairments associated with pediatric brain injury. In this article we describe how the research edition of the PTBI was developed, provide rationale for the areas of assessment, discuss a plan for standardization, and illustrate its use with three children with TBI. DESIGN: The PTBI was constructed to sample the attention, memory, language, reading, writing, metalinguistic, and metacognitive skills that are particularly at risk in pediatric brain injury and that are relevant to the general education curriculum. MATERIAL: The test material for the PTBI was selected on the basis of clinical and experimental evidence that children and adolescents with TBI demonstrate a wide range of cognitive and language deficits. These first appear in the early stages of recovery and often persist but change over time. CONCLUSION: Our goal is to standardize the PTBI so it can be used to establish baseline behaviors and track cognitive-linguistic recovery.- - - - - - - - - - ranking = 132.98152042159keywords = traumatic brain injury, brain injury, traumatic brain, brain, injury (Clic here for more details about this article) |
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