Visuoperceptual Deficits Research Articles

Linguistic and neuropsychological deficits in crossed conduction aphasia. Report of three cases

This study describes the linguistic and neuropsychological findings in three right-handed patients with crossed conduction aphasia. Despite the location of the lesion in the right hemisphere, all patients displayed a combination of linguistic deficits typically found in conduction aphasia following analogous damage to the left hemisphere. Associated cognitive deficits varied across the three patients. In addition, all cases showed deficits classically attributed to non-dominant hemisphere damage (visuoperceptual deficits and reduced figural memory). As a result, lesion–behaviour relationships in our study sample indicate both dominant and non-dominant qualities of the right hemisphere.

Affective language and humor appreciation after right hemisphere brain damage.

Many adults with right hemisphere brain damage exhibit difficulties in the comprehension and expression of emotional language and humor. Affective comprehension deficits range in severity and can be modulated by task and response demands as well as by the strength of emotional content. Expressive emotional language deficits, as characterized by reduced emotional intensity, are more pervasive than comprehension deficits. Deficits in humor appreciation generally affect the ability to integrate an incongruous element (e.g., a punch line) with the preceding context. Several co-occurring disorders (e.g., depression, cognitive and visuoperceptual deficits, and reduced auditory comprehension) may exacerbate problems with affective language and humor. Although some formal measures evaluate humor appreciation, none specifically addresses emotional language. While no hard data exist regarding efficacy of treatment for deficits in affective language or humor processing, several suggestions for such treatment are provided.

Visuoperceptual and visuomotor deficits in developmental stutterers: An exploratory study

Although the cause of stuttering is unknown, there is strong evidence for it being a neuromotor disorder characterised by an abnormality of higher control encompassing not only speech but other motor systems. The aim of this exploratory study was to look for the presence of non-speech/language deficits – in particular, visuomotor and visuoperceptual deficits – in persons who stutter. Twelve moderate to severe developmental stutterers were compared with a group of fluent speakers, matched for age and sex, on a range of computerized sensory-motor tasks. These tasks covered various aspects of visuomotor function – ballistic movement, dynamic steadiness, and several types of tracking – and visuoperceptual function – acuity, static perception, and dynamic perception. A novel technique was used to remove the visuospatial component from tracking performance. Stutterers had slower reaction times, less accurate random tracking, and impaired dynamic visual perception. Severity of stuttering correlated with reaction time and dynamic perception. Removal of the visuoperceptual component from tracking performance indicated that the impaired tracking in the stutterers was predominantly due to reduced dynamic perception. This is the first study to provide preliminary evidence for the presence of non-linguistic visuoperceptual and upper-limb visuomotor tracking deficits in people with moderate to severe stuttering. These findings support a neurogenic aetiology for stuttering and are compatible with evidence of an overactive dopamine system in stutterers.

Normative Data for the Motor-Free Visual Perception Test-Vertical

It is of critical importance for occupational therapists to properly identify visuo-perceptual deficits because of their impact on people's abilities to do many activities of daily living. However, currently there is a lack of knowledge about normal aging of this function. This study presents normative reference data for a test of visual perception frequently used with people with brain injury, the Motor-Free Visual Perception Test-Vertical (MVPT-V). The recruitment strategies were deliberately designed to generate a representative sample of the 50-plus population from different backgrounds. Normative values were obtained from 236 elderly participants. Age and education were found to have a significant impact on performance. These reference values for the MVPT-V will enable therapists to distinguish between normal and pathological aging of visual perception

C ROSSMODAL AGNOSIA FOR FAMILIAR PEOPLE AS A CONSEQUENCE OF RIGHT INFERO POLAR TEMPORAL ATROPHY

A 60-year-old, right-handed woman, with no focal brain lesions, suffered from a progressive impairment in recognising people of personal relevance and public figures familiar to her in the premorbid period. The patient did not suffer from general cognitive deterioration. There was no ecological or clear psychometric evidence of visuoperceptual or visuospatial deficits. Her defective person recognition was not overcome by extra-facial (e.g., observing animated people in their usual surroundings) or extra-visual information (e.g., listening to the voice). Moreover, presenting the correct name in the presence of an unrecognised familiar person failed to prompt her familiarity judgement, or retrieval of the relevant biographical knowledge. The patient also had some recognition difficulties with famous buildings and songs as well as with some common objects. It is argued that the patient's difficulty in identifying familiar people was the consequence of progressive loss of stored exemplars of familiar persons and perhaps also of some other “unique items” (famous songs and monuments) in an independent subsystem of semantics that we term “exemplar semantics.” We discuss the associative (semantic) nature and specificity of the deficit in person knowledge, the possible top-down negative influences of the loss of exemplars in the person recognition system, and the link between the disorders and the right/left temporal lobe.

Normative Data for the Motor-Free Visual Perception Test-Vertical

It is of critical importance for occupational therapists to properly identify visuo-perceptual deficits because of their impact on people's abilities to do many activities of daily living. However, currently there is a lack of knowledge about normal aging of this function. This study presents normative reference data for a test of visual perception frequently used with people with brain injury, the Motor-Free Visual Perception Test-Vertical (MVPT-V). The recruitment strategies were deliberately designed to generate a representative sample of the 50-plus population from different backgrounds. Normative values were obtained from 236 elderly participants. Age and education were found to have a significant impact on performance. These reference values for the MVPT-V will enable therapists to distinguish between normal and pathological aging of visual perception

Neurocognitive development of children with congenital unilateral brain lesion and epilepsy.

The aim of this study was to specify the neuropsychological deficits characteristic of children with unilateral non-progressive brain lesion. In order to assess these specific functions, we used a comprehensive model of congenital hemiparesis with partial epilepsy and newly diagnosed partial epilepsy without hemiparesis. The neuropsychological examination was performed using the NEPSY test battery on 44 children aged from 4 to 9 years. The children were divided into three groups: 18 children suffering from congenital hemiparesis with chronic partial epilepsy, 12 children with newly diagnosed partial epilepsy prior to anti-epileptic treatment, and 14 healthy controls matched by sex, age, and socioeconomic status. Children with congenital hemiparesis and epilepsy had a more clearly expressed cognitive dysfunction, especially in language, visuo-perceptual and memory tasks, than children with newly diagnosed partial epilepsy. The profile of cognitive weakness appears to be diffuse and quite similar in both groups, and it did not demonstrate a clear effect of lateralization, according to the side of epileptic electroencephalogram discharges. Children within both groups are likely to have a high risk of developing attention, phonological, visuo-perceptual, and memory deficits in their life. Especially interesting and surprising was the fact that the newly diagnosed epilepsy group demonstrated impairment not only in attention, visuo-perceptual and short-term memory skills, but also in auditory perception, lexical function, and the comprehension of speech. Therefore, it is recommended that children with epilepsy would undergo neuropsychological examination in order to assess their cognitive abilities.

Role of Perceptual and Organizational Factors in Amnesics' Recall of the Rey-Osterrieth Complex Figure: A Comparison of Three Amnesic Groups

To examine the contribution of visual-perceptual and visual-organizational factors to visual memory in amnesia, Korsakoff, medial temporal, and anterior communicating artery (ACoA) aneurysm amnesics' copy, organization, and recall performance on the Rey-Osterrieth Complex Figure was assessed. Korsakoff patients were matched to medial temporal patients in terms of severity of amnesia, while the ACoA group, which was less severely amnesic, was matched to the Korsakoff patients on performance on executive tasks. Results indicated that while both the ACoA and Korsakoff groups had poorer copy accuracy and organization than controls, only the Korsakoff patients' copy accuracy was worse than the other two amnesic groups. While the Korsakoff patient's visuoperceptual deficits could partially explain this group's poor performance at immediate recall, the Korsakoff group's comparatively worse performance at delayed recall could not be accounted for by poor copy accuracy, reduced visual organization, or even the combined influence of these two factors.

Dyslexie développementale et attention visuo-spatiale

Summary: Developmental dyslexia and visuo-spatial attention. This paper gives an overview of the literature on the visuo-perceptual and visuo-attentional deficits of dyslexic children. The hypothesis that visuo-attentional problems cooccur with dyslexia was assessed through a task of search for a target among distractors. Serial-attentional visual processing was required in one task condition (searchfor 0 among Qs) whereas the other condition involved parallel/automatic processing (search for Q among 0 s). Ten dyslexic subjects constituted the experimental group. Their performance was compared to that of 20 non-dyslexic children, 10 matched for chronological age and 10 for reading age. The performance of dyslexic subjects was similar to that of children matched for chronological age in the parallel/automatic condition. In contrast, their performance differed by an increased search slope front that of the two control groups in the seriallattentional condition. These results suggest the existence of visuo-attentional deficits in dyslexic children. Key words : visual search, parallel vs attentional processing, developmental dyslexia.

The pattern of cognitive impairments in neuroacanthocytosis. A frontosubcortical dementia.

To identify the neuropsychological profiles of patients with neuroacanthocytosis. The medical files of 19 previously reported cases of neuroacanthocytosis were reviewed. Ten of the patients involved had undergone comprehensive cognitive assessments, and their neuropsychological records formed the basis of the present study. Data on discrepancies between estimated optimal and obtained measures of general intelligence and scores on focal cognitive tests of memory, language, visual perception, and frontal lobe executive skills were tabulated and interpreted. Eight of the patients had evidence of general intellectual deterioration. Five patients presented with memory impairment, two of whom showed visuoperceptual deficits. None of the patients showed any significant high-level language deficits. The most consistent findings across cases was evidence of impairment in frontal lobe executive skills and psychiatric morbidity. The cognitive and psychiatric features of the patients suggests that neuroacanthocytosis is a frontosubcortical type of dementia.

The perception of facial emotion across the adult life span

This study was designed to examine changes in the perception of facial emotion across the adult life span. Subjects were 30 young (ages 21 to 39 years), 30 middle‐aged (ages 40 to 59 years), and 30 older (ages 60 to 81 years) normal adult right‐handed females. The three groups of subjects were carefully screened for neurological and psychiatric disorders and for cognitive and visuoperceptual deficits; the groups were closely matched on demographic variables. Subjects were required to identify photographs of facial emotional expressions (Ekman & Friesen, 1976). There were no overall changes in accuracy of perception as a function of age. The ages of posers in the photographs did not influence the perceptual accuracy scores. This study contributes to the literature about the characteristics of normal emotional processing across the adult life span.

Behavioral assessment and treatment of acquired visuoperceptual disorders

Visuoperceptual deficits are common sequelae of damage to either hemisphere of the brain, but are typically more pronounced following injuries involving the right cerebral hemisphere. Common visuoperceptual disorders include visual field cuts, hemi-inattention and hemi-spatial neglect, hemi-perceptual deficits, and gaze and visual pursuit disturbances. A number of behavioral interventions have been developed to teach patients to compensate for acquired visual deficits. Studies addressing assessment and treatment issues in this area are reviewed, and future directions for research are outlined.

Recognition memory for words and faces in primary degenerative dementia of the Alzheimer type and normal old age

The suitability of Warrington's Recognition Memory Test (RMT) for discriminating between patients with dementia of the Alzheimer type and nondemented elderly subjects was tested in a study with 44 patients (aged 59 to 94) and 45 normal elderly (aged 69 to 92). The patients showed a significant memory deficit, both in Recognition Memory for Words (RMW) and Recognition Memory for Faces (RMF), even when the scores were corrected for verbal intelligence score (WAIS Vocabulary) or a measure of visuoperceptual ability (Raven's Coloured Progressive Matrices, CPM). Word-face discrepancy scores did not differentiate between dementia and normal old age. At the 95%-specificity level, the sensitivity of RMW and RMF for the detection of memory impairment in dementia was 81% and 100% for subjects below 80, and, less satisfactory, 59% and 76% for subjects of 80 years or older. Correlational analysis showed that the patients' RMW and RMF scores were moderately correlated (r = .40). The significant correlation (r = .45) between CPM and RMF suggests that visuoperceptual deficits are involved in deficient face recognition.

Brief assessment of cognitive impairment in patients with stroke.

The Stroke Unit Mental Status Examination (SUMSE) has been developed to provide a reliable poststroke test of cognitive functioning that may be administered at bedside. SUMSE was designed to assess major cognitive disorders caused by stroke (eg, language disorders, visuoperceptual deficits, and memory disorders) while avoiding, as much as possible, reliance on patients' English language skills and motor movements. SUMSE's reliability and validity were evaluated by administering it to patients on a stroke rehabilitation unit in conjunction with already validated tests. The results indicated that SUMSE has the potential to become a useful tool for the bedside assessment of mental impairment in stroke patients.

Alcoholic Korsakoff's syndrome: some unresolved issues concerning etiology, neuropathology, and cognitive deficits.

Recent neuropsychological and neuropathological investigations with long-term alcoholics suggest that the etiology and neuropathology of the Wernicke-Korsakoff syndrome are more complex than previously believed. While problem solving and visuoperceptual deficits seem to develop slowly during decades of alcoholism, the amnesic symptoms associated with Korsakoff's syndrome may appear acutely when severe malnutrition and alcoholism are combined. Furthermore, the report that alcoholic Korsakoff patients, like patients with Alzheimer's Disease, have endured a substantial neuronal loss in the nucleus basalis of Meynert has questioned the role of the medial diencephalon in the alcoholic patients' amnesic syndrome. Some initial demonstrations of similarities in the memory disorders of alcoholic Korsakoff and Alzheimer patients indicate that Korsakoff's syndrome may be more accurately characterized as a "basal forebrain" than as a "diencephalic" amnesia.

The profile of recovery from stroke and factors influencing outcome.

The recovery from stroke of 154 survivors out of 255 stroke patients was analyzed. The outcomes documented were: discharge from hospital, activities of daily living (ADL) and return to work. A clear improvement in neurological and neuropsychological deficits was seen from the acute stage to three months, and this continued to twelve months, but to a lesser degree. 69% and 78% respectively, of the patients were at home three and twelve months after stroke. Independence in ADL increased from 32% acutely to 62% and 68% by three and twelve months, respectively. Of those gainfully employed prior to stroke, 55% had returned to work after twelve months. As a group, SAH patients seemed to recover better, but, for those that could be age-matched with infarction patients, there was no difference in outcome. Old age, acute stage hemiparesis, impairment of intelligence and memory, visuoperceptual deficits, nonadequate emotional reactions, and living alone all had a major negative influence on outcome. This study suggests that neurological and neuropsychological deficits, as well as emotional reactions, influence the outcomes after stroke, and all should be taken into consideration in prognosis.

Some Comparisons of the Memory and Visuoperceptive Deficits of Chronic Alcoholics and Patients with Korsakoff's Disease

Some Comparisons of the Memory and Visuoperceptive Deficits of Chronic Alcoholics and Patients with Korsakoff's Disease