97 research outputs found
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Lesions impairing regular versus irregular past tense production
We investigated selective impairments in the production of regular and irregular past tense by examining language performance and lesion sites in a sample of twelve stroke patients. A disadvantage in regular past tense production was observed in six patients when phonological complexity was greater for regular than irregular verbs, and in three patients when phonological complexity was closely matched across regularity. These deficits were not consistently related to grammatical difficulties or phonological errors but were consistently related to lesion site. All six patients with a regular past tense disadvantage had damage to the left ventral pars opercularis (in the inferior frontal cortex), an area associated with articulatory sequencing in prior functional imaging studies. In addition, those that maintained a disadvantage for regular verbs when phonological complexity was controlled had damage to the left ventral supramarginal gyrus (in the inferior parietal lobe), an area associated with phonological short-term memory. When these frontal and parietal regions were spared in patients who had damage to subcortical (n = 2) or posterior temporo-parietal regions (n = 3), past tense production was relatively unimpaired for both regular and irregular forms. The remaining (12th) patient was impaired in producing regular past tense but was significantly less accurate when producing irregular past tense. This patient had frontal, parietal, subcortical and posterior temporo-parietal damage, but was distinguished from the other patients by damage to the left anterior temporal cortex, an area associated with semantic processing. We consider how our lesion site and behavioural observations have implications for theoretical accounts of past tense production
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Measures of functional, real-world communication for aphasia: a critical review
Purpose: Aphasia is a language impairment caused by acquired brain damage such as stroke. For successful rehabilitation, a thorough understanding of naturalistic, real-world communication is imperative, as this is the behaviour speech and language therapy (SLT) ultimately aims to improve. In the field of aphasiology, there currently is a lack of consensus about the way in which communication should be measured. Underlying this is a fundamental lack of agreement over what real-world communication entails and how it should be defined.
Method: In this critical review, we review the instruments that are currently used to quantify functional, real-world communication in people with aphasia (PWA). Each measure is checked against a newly proposed, comprehensive, theoretical framework of situated language use, which defines communication as: (1) interactive, (2) multimodal, and (3) based on context (common ground).
Results: The instrument that best fits the theoretical definition of situated language use and allows for the quantification of communicative ability is the Scenario Test.
Conclusions: This article provides a start in a more systematic and theoretically founded approach to the study and measurement of functional, real-world communication in aphasia. More work is needed to develop an instrument that can quantify communicative ability across different aphasia types and severities
Motion seen and understood: interactions between language comprehension and visual perception.
Embodied theories of cognition state that the body plays a central role in cognitive representation. Under this description semantic representations, which constitute the meaning of words and sentences, are simulations of real experience that directly engage sensory and motor systems. This predicts interactions between comprehension and perception at low levels, since both engage the same systems, but the majority of evidence comes from picture judgements or visuo-spatial attention therefore it is not clear which visual processes are implicated. In addition, most of the work has concentrated on sentences rather than single words although theories predict that the semantics of both should be grounded in simulation. This investigation sought to systematically explore these interactions, using verbs that refer to upwards or downwards motion and sentences derived from the same set of verbs. As well as looking at visuo-spatial attention, we employed tasks routinely used in visual psychophysics that access low levels of motion processing. In this way we were able to separate different levels of visual processing and explore whether interactions between comprehension and perception were present when low level visual processes were assessed or manipulated. The results from this investigation show that: (1) There are bilateral interactions between low level visual processes and semantic content (lexical and sentential). (2) Interactions are automatic, arising whenever linguistic and visual stimuli are presented in close temporal contiguity. (3) Interactions are subject to processes within the visual system such as perceptual learning and suppression. (4) The precise content of semantic representations dictates which visual processes are implicated in interactions. The data is best explained by a close connection between semantic representation and perceptual systems when information from both is available it is automatically integrated. However, it does not support the direct and unmediated commitment of the visual system in the semantic representation of motion events. The results suggest a complex relationship between semantic representation and sensory-motor systems that can be explained by combining task specific processes with either strong or weak embodiment
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Prevalence of pain flashbacks in post-traumatic stress disorder arising from exposure to multiple traumas or childhood traumatization
Background: Flashbacks are a form of multisensory memory that are experienced with a ‘happening in the present’ quality. Pain flashbacks are a re-experiencing of pain felt at the time of a traumatic event. It is unclear how common pain flashbacks are.
Aims: The current study was designed primarily to assess the prevalence of pain flashbacks in a sample of patients with post-traumatic stress disorder (PTSD).
Methods: We assessed the prevalence of pain flashbacks over a period of two years in patients (n = 166) referred to a psychological trauma service in the UK. Patients underwent a clinical screen for PTSD, and completed a self-report measure of pain flashbacks.
Results: Pain flashbacks were classified as present in 49% of a sample of complex trauma patients meeting criteria for PTSD. Pain flashbacks were positively associated with the extent of pain at the time of trauma.
Conclusions: Pain re-experiencing in PTSD, and its relative absence in non-clinical populations, supports an account of memory in which perceptual details can be re- experienced when memories have been encoded under conditions of extreme stress. It may be possible to conceptualize some cases of unexplained pain as pain flashbacks, or of having a trauma origin
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What is functional communication? A theoretical framework for real-world communication applied to aphasia rehabilitation
Aphasia is an impairment of language caused by acquired brain damage such as stroke or traumatic brain injury, that affects a person’s ability to communicate effectively. The aim of rehabilitation in aphasia is to improve everyday communication, improving an individual’s ability to function in their day-to-day life. For that reason, a thorough understanding of naturalistic communication and its underlying mechanisms is imperative. The field of aphasiology currently lacks an agreed, comprehensive, theoretically founded definition of communication. Instead, multiple disparate interpretations of functional communication are used. We argue that this makes it nearly impossible to validly and reliably assess a person’s communicative performance, to target this behaviour through therapy, and to measure improvements post-therapy. In this article we propose a structured, theoretical approach to defining the concept of functional communication. We argue for a view of communication as “situated language use”, borrowed from empirical psycholinguistic studies with non-brain damaged adults. This framework defines language use as: (1) interactive, (2) multimodal, and (3) contextual. Existing research on each component of the framework from non-brain damaged adults and people with aphasia is reviewed. The consequences of adopting this approach to assessment and therapy for aphasia rehabilitation are discussed. The aim of this article is to encourage a more systematic, comprehensive approach to the study and treatment of situated language use in aphasia
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Early childhood predictors of anxiety in early adolescence
This longitudinal study examined a multitude of early childhood predictors of anxiety symptoms and disorders over an 8-year period. The purpose of the study was to identify early life predictors of anxiety across childhood and early adolescence in a sample of at-risk children. The sample included 202 preschool children initially identified as behaviorally inhibited or uninhibited between the ages of 3 years 2 months and 4 years 5 months. Temperament and familial environment variables were assessed using observation and parent report at baseline. Anxiety symptoms and disorders were assessed using questionnaires and diagnostic interviews at baseline (age 4), and at age 6, 9 and 12 years. In line with our hypotheses, the findings showed that preschool children were more likely to experience anxiety symptoms and disorders over time i) when the child was inhibited, ii) when there was a history of maternal anxiety disorders or iii) when mothers displayed high levels of overinvolvement. Further, the study identified a significant interaction effect between temperament and maternal overvinvolvement such that behaviorally inhibited preschoolers had higher anxiety symptoms at age 12, only in the presence of maternal overinvolvement at age 4. The increased risk of anxiety in inhibited children was mitigated when mothers demonstrated low levels of overinvolvement at age 4. This study provides evidence of both additive and interactive effects of temperament and family environment on the development of anxiety and provides important information for the identification of families who will most likely benefit from targeted early intervention
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MaLT - combined motor and language therapy tool for brain injury patients using Kinect
Background: The functional connectivity and structural proximity of elements of the language and motor systems result in frequent co-morbidity post brain injury. Although rehabilitation services are becoming increasingly multidisciplinary and "integrated", treatment for language and motor functions often occurs in isolation. Thus, behavioural therapies which promote neural reorganisation do not reflect the high intersystem connectivity of the neurologically intact brain. As such, there is a pressing need for rehabilitation tools which better reflect and target the impaired cognitive networks. Objectives: The objective of this research is to develop a combined high dosage therapy tool for language and motor rehabilitation. The rehabilitation therapy tool developed, MaLT (Motor and Language Therapy), comprises a suite of computer games targeting both language and motor therapy that use the Kinect sensor as an interaction device. The games developed are intended for use in the home environment over prolonged periods of time. In order to track patients' engagement with the games and their rehabilitation progress, the game records patient performance data for the therapist to interrogate. Methods: MaLT incorporates Kinect-based games, a database of objects and language parameters, and a reporting tool for therapists. Games have been developed that target four major language therapy tasks involving single word comprehension, initial phoneme identification, rhyme identification and a naming task. These tasks have 8 levels each increasing in difficulty. A database of 750 objects is used to programmatically generate appropriate questions for the game, providing both targeted therapy and unique gameplay every time. The design of the games has been informed by therapists and by discussions with a Public Patient Involvement (PPI) group. Results: Pilot MaLT trials have been conducted with three stroke survivors for the duration of 6 to 8 weeks. Patients' performance is monitored through MaLT's reporting facility presented as graphs plotted from patient game data. Performance indicators include reaction time, accuracy, number of incorrect responses and hand use. The resultant games have also been tested by the PPI with a positive response and further suggestions for future modifications made. Conclusion: MaLT provides a tool that innovatively combines motor and language therapy for high dosage rehabilitation in the home. It has demonstrated that motion sensor technology can be successfully combined with a language therapy task to target both upper limb and linguistic impairment in patients following brain injury. The initial studies on stroke survivors have demonstrated that the combined therapy approach is viable and the outputs of this study will inform planned larger scale future trials
Grasp It Loudly! Supporting Actions with Semantically Congruent Spoken Action Words
Evidence for cross-talk between motor and language brain structures has accumulated over the past several years. However, while a significant amount of research has focused on the interaction between language perception and action, little attention has been paid to the potential impact of language production on overt motor behaviour
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The anterior temporal lobes support residual comprehension in Wernicke’s aphasia
Wernicke’s aphasia occurs following a stroke to classical language comprehension regions in the left temporoparietal cortex. Consequently, auditory-verbal comprehension is significantly impaired in Wernicke’s aphasia but the capacity to comprehend visually presented materials (written words and pictures) is partially spared. This study used fMRI to investigate the neural basis of written word and picture semantic processing in Wernicke’s aphasia, with the wider aim of examining how the semantic system is altered following damage to the classical comprehension regions. Twelve participants with Wernicke’s aphasia and twelve control participants performed semantic animate-inanimate judgements and a visual height judgement baseline task. Whole brain and ROI analysis in Wernicke’s aphasia and control participants found that semantic judgements were underpinned by activation in the ventral and anterior temporal lobes bilaterally. The Wernicke’s aphasia group displayed an “over-activation” in comparison to control participants, indicating that anterior temporal lobe regions become increasingly influential following reduction in posterior semantic resources. Semantic processing of written words in Wernicke’s aphasia was additionally supported by recruitment of the right anterior superior temporal lobe, a region previously associated with recovery from auditory-verbal comprehension impairments. Overall, the results concord with models which indicate that the anterior temporal lobes are crucial for multimodal semantic processing and that these regions may be accessed without support from classic posterior comprehension regions
Making the Invisible Visible: Verbal but Not Visual Cues Enhance Visual Detection
Background: Can hearing a word change what one sees? Although visual sensitivity is known to be enhanced by attending to the location of the target, perceptual enhancements of following cues to the identity of an object have been difficult to find. Here, we show that perceptual sensitivity is enhanced by verbal, but not visual cues. Methodology/Principal Findings: Participants completed an object detection task in which they made an object-presence or-absence decision to briefly-presented letters. Hearing the letter name prior to the detection task increased perceptual sensitivity (d9). A visual cue in the form of a preview of the to-be-detected letter did not. Follow-up experiments found that the auditory cuing effect was specific to validly cued stimuli. The magnitude of the cuing effect positively correlated with an individual measure of vividness of mental imagery; introducing uncertainty into the position of the stimulus did not reduce the magnitude of the cuing effect, but eliminated the correlation with mental imagery. Conclusions/Significance: Hearing a word made otherwise invisible objects visible. Interestingly, seeing a preview of the target stimulus did not similarly enhance detection of the target. These results are compatible with an account in which auditory verbal labels modulate lower-level visual processing. The findings show that a verbal cue in the form of hearing a word can influence even the most elementary visual processing and inform our understanding of how language affect
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