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At least 775 records · Page 43Linked to original sources
PubMed2004

Visual-spatial processing and dimensions of schizophrenia: a preliminary study on 62 schizophrenic subjects.

The aim of the study was to explore the relationships between the performance in figure-ground segregation and the clinical dimensions in schizophrenia. Sixty-two schizophrenic subjects filled out the embedded figures test (EFT) and the schizophrenic symptomatology was rated using the brief psychiatric rating scale (BPRS). The BPRS items were grouped into four categories: positive, negative, general and disorganization. The results showed in male schizophrenics negative and significant correlations between EFT scores and negative or disorganization subscales. Taken into account that in schizotypic subjects EFT scores was negatively correlated with negative dimension of schizotypy we suggested that those relationship could constitute a trait of the disease.

Adult↗
PubMed2004

Auditory deficits in visuospatial neglect patients.

Since the pioneering experimental work of Bisiach et al. (1984) on deficits in sound localisation associated with unilateral brain lesions and visual neglect, a number of systematic investigations have examined auditory processing in visuospatial neglect patients. Evidence from a variety of experimental paradigms has revealed some auditory deficits in detection and identification tasks, during bilateral stimulation; plus localisation deficits for single sounds. These deficits emerge predominantly for contra-lesional sounds, although some auditory disturbances applying to both contra- and ipsilesional sounds have also been documented. Here we review evidence suggesting that some of these auditory deficits arise in relatively high-level stages of spatial processing. In addition, we present new analyses showing that auditory deficits in identification and localisation tasks often correlate with clinical measures of visual neglect, across a variety of different studies and tasks. This empirical relation suggests that a disturbance of multisensory spatial processing may often account for the joint auditory and visual spatial deficits in neglect patients, although rarer dissociations between the modalities should also be considered.

Auditory Perception↗
PubMed1995

The role of visual discrimination disorders and neglect in perceptual categorization deficits in right and left hemisphere damaged patients.

This study was designed to investigate the role of visual sensory deficits and neglect in perceptual categorization deficits in a group of 35 patients with unilateral cerebral lesions. From theoretical point of view, it was expected that right hemisphere lesions would play a critical role in eliciting perceptual categorization deficits which could not be accounted for by visual sensory deficits or neglect. The results revealed that perceptual categorization deficits were not confined to RHD patients, but they were also found in LHD patients. RHD patients were impaired regardless of the nature of the task (verbal vs. nonverbal), while LHD patients were impaired on nonverbal tasks, and in a lesser degree on verbal tasks. In both braindamaged groups, perceptual categorization deficits were highly associated with visual sensory deficits, however, perceptual categorization deficits were also found without impairments in the visual sensory system. Neglect to be less important determinant of perceptual categorization deficits. The present findings are discussed in the light of Warrington's model of object agnosia.

Adult↗
PubMed2003

Automatic processing of verbal emotion stimuli in schizophrenia.

In the present study, automatic processing of verbal emotion stimuli was investigated as a function of affective symptoms, emotional state and trait characteristics of chronic schizophrenia patients. A sequential pronunciation priming task was administered to 30 schizophrenia patients with a flat affect expression, 30 schizophrenia patients suffering from anhedonia, 28 schizophrenia patients not suffering from anhedonia or flat affect, and 30 healthy subjects to assess affective and semantic priming effects. The Scale for the Assessment of Negative Symptoms (Andreasen, British Journal of Psychiatry, 1989, 155, 53-58) was applied to evaluate the flat affect and anhedonia, and to categorize patients into groups. Schizophrenia patients did not differ from healthy subjects in affective and semantic priming scores. However, affective priming based on positive primes was inversely correlated with negative state and trait affectivity, and positively correlated with trait joy in the patient sample. These results support the view that a decrement in automatic processing facilitation of positive valence might play a role in the development of negative emotions. The symptoms of flat affect and anhedonia do not appear to be associated with impairments in the automatic processing of verbal emotional material in schizophrenia.

Adult↗
PubMed2004

Do the siblings of schizophrenia patients demonstrate affect perception deficits?

Affect perception deficits have been extensively documented in schizophrenia and are associated with the social dysfunction that is characteristic of this disorder. The two previous studies examined facial affect perception in genetically at-risk samples and yielded mixed results. The current study was designed to provide a rigorous test of affect perception abilities among schizophrenia patients (n=58), their biological siblings without psychosis (n=51), and nonpsychiatric controls (n=49). Participants completed three measures of affect perception, including facial, vocal, and combined modality. Schizophrenia patients performed significantly worse than controls on two of the three affect perception tests as well as a composite index based on all three tests. The performance of the sibling group fell between the patient and control groups on each of the affect perception tests. However, group differences achieved statistical significance only for the composite index with the siblings performing significantly worse than controls and significantly better than the schizophrenia group. These findings demonstrate that subtle deficits in affect perception are detectable in the unaffected siblings of schizophrenia patients when multiple measures of different types of affect perception abilities are used in combination.

Adult↗
PubMed2003

Neurocognitive functioning in children with type-1 diabetes with and without episodes of severe hypoglycaemia.

Previous studies have shown that recurrent severe hypoglycaemia can cause long-term cognitive impairment in children with type-1 diabetes, but the results are controversial, possibly due to the heterogeneity of samples and lack of comprehensive neuropsychological assessments of children. The aim of this study was to assess the effects of diabetes and severe hypoglycaemia on the neurocognitive functioning of children with a standardized, wide age-range neuropsychological test battery designed for the assessment of children. Eleven children with diabetes and a history of severe hypoglycaemia, 10 children with diabetes without a history of severe hypoglycaemia, and 10 healthy control children (a total of 31 children: 14 males and 17 females, age range 5 years 6 months to 11 years 11 months, mean 9 years 4 months, SD 1 year 11 months) were studied using the Wechsler Intelligence Scale for Children-Revised (WISC-R) and the NEPSY, a Developmental Neuropsychological Assessment. The NEPSY assessed development in attention and executive functions, language, sensorimotor functions, visuospatial processing, and learning and memory. Children with a history of severe hypoglycaemia had more neuropsychological impairments, more learning difficulties (as reported by parents), and needed more part-time special education than those in the other groups. Significant differences were found in verbal short-term memory and phonological processing. Results suggest that severe hypoglycaemia is a risk factor for learning due to deficits in auditory-verbal functioning.

Child↗
PubMed2001

Face processing in schizophrenia: defining the deficit.

BACKGROUND: Abnormalities of face affect naming and face recognition occur in schizophrenia but it is not clear whether the deficits reflect wider underlying impairments of perception, memory, language or executive function. METHOD: Twenty-six patients with schizophrenia were compared with 23 healthy volunteers on neuropsychological tests and tests of face and affect processing. Face and non-face tests were compared at four levels of processing: visuo-spatial perception, recognition memory, language and naming, and executive function. We examined relationships with drug dose, duration of illness and pre-morbid and current IQ. RESULTS: Patients and controls did not differ in estimated pre-morbid IQ but current IQ was 12 points lower in patients. At each level of processing there were correlated deficits of face and non-face processing in the patients that were mostly independent of IQ decline. Impaired face and non-face visuo-spatial function and recognition performance were generally correlated with drug dose. Impairments in naming face emotions were correlated with other non-face naming tasks independently of drug dose. Patients performed less well than controls in classifying faces by emotion while ignoring identity and this was associated with poorer performance in Wisconsin Card Sorting. CONCLUSIONS: The pattern of results suggests that deficits in face processing reflect three wider neuropsychological impairments: a drug-related impairment of visual imagery, and disease-related impairments of semantic retrieval and executive function.

Adult↗
PubMed2002

Defining the broader phenotype of autism: genetic, brain, and behavioral perspectives.

Achieving progress in understanding the cause, nature, and treatment of autism requires an integration of concepts, approaches, and empirical findings from genetic, cognitive neuroscience, animal, and clinical studies. The need for such integration has been a fundamental tenet of the discipline of developmental psychopathology from its inception. It is likely that the discovery of autism susceptibility genes will depend on the development of dimensional measures of broader phenotype autism traits. It is argued that knowledge of the cognitive neuroscience of social and language behavior will provide a useful framework for defining such measures. In this article, the current state of knowledge of the cognitive neuroscience of social and language impairments in autism is reviewed. Following from this, six candidate broader phenotype autism traits are proposed: (a) face processing, including structural encoding of facial features and face movements, such as eye gaze; (b) social affiliation or sensitivity to social reward, pertaining to the social motivational impairments found in autism; (c) motor imitation ability, particularly imitation of body actions; (d) memory, specifically those aspects of memory mediated by the medial temporal lobe-prefrontal circuits; (e) executive function, especially planning and flexibility; and (f) Language ability, particularly those aspects of language that overlap with specific language impairment, namely, phonological processing.

Autistic Disorder↗
PubMed2001

Understanding metaphors and idioms: a single-case neuropsychological study in a person with Down syndrome.

The ability of subject F.F., diagnosed with Down syndrome, to appreciate nonliteral (interpreting metaphors and idioms) and literal (vocabulary knowledge, including highly specific and unusual items) aspects of language was investigated. F.F. was impaired in understanding both metaphors and idioms, while her phonological, syntactic and lexical-semantic skills were largely preserved. By contrast, some aspects of F.F.'s executive functions and many visuospatial abilities were defective. The suggestion is made that the interpretation of metaphors and idioms is largely independent of that of literal language, preserved in F.F., and that some executive aspects of working memory and visuospatial and imagery processes may play a role.

Adult↗
PubMed2003

Anomalies of subjective experience in schizophrenia and psychotic bipolar illness.

OBJECTIVE: Contemporary psychopathology, as a result of behaviourally dominated epistemological stance, downplays anomalies of the patient's subjectivity. This neglect has probably deleterious consequences for research in the causes and the boundaries of the schizophrenia spectrum conditions. The purpose of this study is to explore frequency of qualitative, not-yet-psychotic, anomalies of subjective experience in patients with residual schizophrenia and psychotic bipolar illness in remission. METHOD: The patients were examined with the Danish version of the Bonn Scale for the Assessment of Basic Symptoms (BSABS). Anomalies of experience were condensed into rational scales with good internal consistencies. RESULTS: Diagnosis of schizophrenia was associated with elevated scores on the scales measuring perplexity (loss of immediate meaning), disorders of perception, disorders of self-awareness, and marginally so, disorders of cognition. CONCLUSION: These findings, in conjunction with those from other, methodologically similar studies, suggest that certain anomalies of subjective experience aggregate significantly in schizophrenia. These experiential anomalies appear to be relevant for early differential diagnosis and therefore potentially useful in the preonset detection of the schizophrenia spectrum illness.

Adult↗
PubMed2001

Dissociations of the night: individual differences in sleep-related experiences and their relation to dissociation and schizotypy.

The author examined the associations among sleep-related experiences (e.g., hypnagogic hallucinations, nightmares, waking dreams, and lucid dreams), dissociation, schizotypy, and the Big Five personality traits in 2 large student samples. Confirmatory factor analyses indicated that (a) dissociation and schizotypy are strongly correlated-yet distinguishable-constructs, and (b) the differentiation between them can be enhanced by eliminating detachment/depersonalization items from the dissociation scales. A general measure of sleep experiences was substantially correlated with both schizotypy and dissociation (especially the latter) and more weakly related to the Big Five. In contrast, an index of lucid dreaming was weakly related to all of these other scales. These results suggest that measures of dissociation, schizotypy, and sleep-related experiences all define a common domain characterized by unusual cognitions and perceptions.

Adult↗
PubMed2004

Identification of tone duration, line length, and letter position: an experimental approach to timing and working memory deficits in schizophrenia.

Patients with schizophrenia display numerous cognitive deficits, including problems in working memory, time estimation, and absolute identification of stimuli. Research in these fields has traditionally been conducted independently. We examined these cognitive processes using tasks that are structurally similar and that yield rich error data. Relative to healthy control participants (n = 20), patients with schizophrenia (n = 20) were impaired on a duration identification task and a probed-recall memory task but not on a line-length identification task. These findings do not support the notion of a global impairment in absolute identification in schizophrenia. However, the authors suggest that some aspect of temporal information processing is indeed disturbed in schizophrenia.

Adult↗
PubMed2006

Cognitive decline in old age: separating retest effects from the effects of growing older.

Repeated administration of cognitive tests improves test performance, making it difficult for researchers to gauge the true extent of age-related cognitive decline. The authors examined this issue using data from the Rush Religious Orders Study and linear mixed-effects models. At annual intervals for up to 8 years, more than 800 older Catholic clergy members completed the same set of 19 cognitive tests from which previously established composite measures of cognitive domains were derived. Retest effects on some measures were substantial and continued to accumulate even after 8 annual test readministrations, but effects on other measures were minimal. Across cognitive measures, retest effects were not related to age, sex, or education. Individual differences in retest effects were substantial but not consistent across cognitive measures. The results suggest that retest-based improvement in cognitive test performance can be substantial and persistent.

Aged↗
PubMed1997

Depressive symptoms and alterations in sucrose taste perception: cognitive bias or a true change in sensitivity?

Previous studies have reported elevated taste thresholds in depressed subjects, but those studies did not control for changes in response bias. The current study used signal detection analyses to address this shortcoming. Sucrose detection thresholds were measured (1) in subjects with high and low Hamilton Depression Rating Scale (HAM-D) scores who did not meet standard criteria for current Major Depressive Episode (MDE); and (2) in subjects who did fulfil standard criteria for MDE. Subjects with low HAM-D scores produced significantly more false alarms than the other two groups, but taste sensitivity, as indexed by d', did not vary significantly across groups. These results suggest that changes in response bias underlie previously reported increases in sucrose taste thresholds in depressed subjects.

Adult↗
PubMed2004

A meme's eye view of speech-language pathology.

In this article, the reason why certain terms, labels, and ideas prevail, whereas others fail to gain acceptance, will be considered. Borrowing the concept of "meme" from the study of evolution of ideas, it will be clear why language-based and phonological disorders have less widespread appeal than, for example, auditory processing and sensory integration disorders. Discussion will also center on why most speech-language pathologists refer to themselves as speech therapists or speech pathologists, and why it is more desirable to have dyslexia than to have a reading disability. In a meme's eye view, science and logic do not always win out because selection favors ideas (memes) that are easy to understand, remember, and copy. An unfortunate consequence of these selection forces is that successful memes typically provide superficially plausible answers for complex questions.

Aphasia↗
PubMed2004

Stroke and neurodegenerative disorders. 3. Stroke: rehabilitation management.

UNLABELLED: This self-directed learning module highlights common rehabilitation issues in stroke survivors. Topics include spasticity, constraint-induced movement therapy, partial body weight-supported treadmill training, virtual reality training, vestibular retraining, aphasia treatment, and cognitive retraining. It is part of the study chapter on stroke and neurodegenerative disorders in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. OVERALL ARTICLE OBJECTIVES: (a) To identify and review the treatment options for poststroke spasticity; (b) to review the use of body weight-supported treadmill training in stroke patients; (c) to describe virtual reality training as an adjunct in stroke rehabilitation; (d) to review vestibular rehabilitation; (e) to discuss advances in aphasia treatment; (f) to discuss cognitive retraining; and (g) to provide an update on treatment of neglect syndromes.

Activities of Daily Living↗
PubMed2006

Neuropsychological profile of persons with anoxic brain injury: differences regarding physiopathological mechanism.

PRIMARY OBJECTIVE: To determine the neuropsychological profile of persons with anoxic brain injury. METHODS AND PROCEDURES: A retrospective study on a population of persons with anoxic brain injury admitted to a Brain Injury Unit (Institut Guttmann, Spain) from 1995-2003. The sample was divided according to physiopathological mechanisms in two sub-groups: ischemic anoxia (21 cases) and hypoxemic anoxia (11 cases). Functions assessed included orientation, attention, language, visuo-perceptive and visuo-constructive processing and verbal memory. RESULTS: Neuropsychological assessment showed diffuse cognitive impairment in all assessed functions. Episodes of ischemic anoxia caused more severe verbal memory and learning problems than episodes of hypoxemic anoxia. CONCLUSIONS: This study shows that memory problems are the most prominent and relevant impairment, although all other cognitive functions are also impaired, affecting both memory itself and general behaviour. Statistical analysis also provides preliminary evidence on the different profile of memory impairment whether cerebral anoxia had hypoxic or ischemic origin.

Adult↗