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G Goldenberg

Publications and source records attributed to G Goldenberg.

At least 55 records · Page 3Linked to original sources
PubMed1992

Behavioural and psychosocial sequelae of severe closed head injury and regional cerebral blood flow: a SPECT study.

Thirty six patients (31 male, 5 female) who had suffered severe closed head injury were re-examined at an average of 39.3 (SD 12.8, range 7-66) months after the injury. Behavioural symptoms were measured using the Giessen test. The relatives' reports were used for data analysis to ensure that results were valid. The neurophysical impairment subscale of the Glasgow assessment schedule was completed by two neurologists, and the number connection test was completed by each patient. The adjective mood scale was completed by each relative. All patients were investigated by single photon emission computerised tomography (SPECT). Exploratory factor analysis using the principal components method was carried out separately for SPECT results and psychological measures and correlations were sought between the resulting factors. Factor analysis of the data from the Giessen test identified social isolation, disinhibition, and aggressive behaviour as major components of post-traumatic personality changes; it indicates that these behavioural features are independent of the level of neurological and neuropsychological impairment, which loaded on a single independent factor. Relatives' psychic health seemed to be relatively resistant to physical and cognitive disability and was mainly affected by disinhibitive behaviour. The highest correlation was between frontal flow indices and disinhibitive behaviour (p less than 0.01): the severity of disinhibition increased with lower frontal flow rates. There was a significant but somewhat weaker correlation (p less than 0.05) between flow indices of the left cerebral hemisphere and social isolation. Low flow values of the right brain regions were related to aggressive behaviour (p less than 0.05). Neurological and cognitive impairment correlated negatively with the thalamus; worse neurological and cognitive performance indicate by raised scores on the neurophysical scale and on the number connection test was associated with low thalamic flow values. The results support the importance of lesion location in the production of post traumatic behavioural disorders.

Adolescent↗
PubMed1991

HM-PAO-SPECT in persistent vegetative state after head injury: prognostic indicator of the likelihood of recovery?

Management of patients presenting with traumatic persistent vegetative state (PVS) calls for extensive resources. The ability to predict whether or not a patient is likely to recover is a critical issue. In 12 patients with PVS admitted consecutively for early rehabilitation after head injury, pattern of brain activity was measured by 99mTc-hexamethyl-propylenamineoxime (99mTc-HM-PAO) brain SPECT (single photon emission computer tomography). All patients were re-investigated after a mean observation period of 3 years. A global reduction of cortical blood flow was a reliable predictor of poor long-term outcome, but the demonstration of only focal deficits did not reliably indicate a favourable outcome. Brain SPECT may help to improve outcome prediction in patients with traumatic PVS.

Adolescent↗
PubMed1991

Contributions of occipital and temporal brain regions to visual and acoustic imagery--a spect study.

Regional cerebral blood flow (rCBF) was assessed by means of HMPAO-SPECT in two experimental groups. In a control condition both groups listened to abstract words, in the experimental condition they heard five names of objects. One group was advised to form visual images of the objects, the other group was advised to form acoustic images of the sounds made by these objects. Post-experimental questionnaires revealed that most of the subjects in the acoustic imagery condition had had visual images in addition to the acoustic ones. Both imagery conditions lead to approximately equal increases of rCBF in the left inferior occipital region and in the left thalamus. Flow increases in both hippocampal regions and the right inferior and superior temporal regions were larger in the acoustic than in the visual imagery condition. It is concluded that only the activation of left inferior occipital and left thalamic regions can be interpreted as being related to modality-specific visual aspects of imagery.

Auditory Perception↗
PubMed1991

Visual imagery and knowledge about the visual appearance of objects in patients with posterior cerebral artery lesions.

The purpose of this study was to explore whether patients with left posterior cerebral artery (PCA) lesions have defective mental visual imagery and to differentiate whether such a deficit stems from a loss of knowledge about the visual appearance of objects or from an inability to create mental visual images out of preserved visual knowledge. Normal controls and patients with either left or right PCA lesions were asked to verify low- and high-imagery sentences and then to verify pictorial representations of the predicates of high-imagery sentences. High-imagery questions concerned either the shape or the color of objects. In addition, perceptual discrimination of shape and color was assessed. Patients with right PCA lesions were impaired on the perceptual discrimination tasks. Left PCA patients did not significantly differ from controls on low-imagery sentences but scored significantly lower on shape and color questions. Their impairment was distinctly more severe with the pictorial than with the verbal versions of shape and color questions. In comparison to patients with occipital left PCA lesions, patients with temporo-occipital left PCA lesions were selectively impaired on verbal and visual color questions. It is concluded that patients with left PCA lesions lack knowledge about shape and color of objects, but that their ability to convert visual knowledge into mental images is preserved.

Analysis of Variance↗
PubMed1991

[Prognostic factors in rehabilitation after severe craniocerebral injuries].

Even with modern standards of intensive care management and rehabilitation services, severe head injury often results in permanent disability. A review of the literature concerning predictors of outcome after severe head injury is presented. The early identification of those factors which are of greatest significance in determining outcome is of essential value in the appropriate management of rehabilitation therapy. In many cases of severe head injury a reliable assessment of prognosis can be made on the basis of level of coma and brainstem dysfunction, reflecting type and extent of the traumatic brain lesion. Additionally, a broad spectrum of neuroradiological and electrophysiological investigations, as well as measurements of regional cerebral blood flow have been demonstrated to be helpful in establishing rehabilitation prognosis. In studies using a multivariate statistical design, initial level of coma (i.e. initial Glasgow Coma Score), brainstem reflexes, intracranial pressure assessment, the presence/absence of an additional thoracic injury, and age emerged as independent early predictors of outcome after severe head injury. The presence of previous brain damage also seems extremely important. In contrast, the prognostic value of pretraumatic personality factors and of the psychosocial status of the head injured patient requires additional research. Comparison among studies is hindered by differences in patient samples, timing of assessments, and various outcome measures with respect to rehabilitation management.

Brain Damage, Chronic↗
PubMed1991

Thalamic ischemia in transient global amnesia: a SPECT study.

We performed 99mTc-HMPAO SPECT in a patient during transient global amnesia and twice thereafter. SPECT during the attack showed a significant diminution of regional blood flow in the left thalamus and a less marked diminution in the right thalamus. Quantitative evaluation of global 99mTc-HMPAO uptake indicated a diffuse depression of cerebral blood flow. At follow-up to 40 days after the attack, global uptake and thalamic flow indices normalized, but there was a persistent reduction of left frontal flow values.

Amnesia↗
PubMed1990

Performance of concurrent non-motor tasks in Parkinson's disease.

The purpose of the study was to examine the hypothesis that patients with Parkinson's disease have a general inability to cope with concurrent task demands, and that this inability stems from a lack of attentional control of motor and cognitive activities. Performance on a verbal and on a visuospatial memory task was compared with performance on largely identical memory tasks which were combined with concurrent non-motor tasks. As a further index of a possible weakness of the attentional control of cognitive function order memory was assessed and compared with item memory. Both parkinsonian patients and controls showed a decline of memory performance when the concurrent task was introduced, but the degree of decline did not differ between groups. Parkinsonian patients scored worse than controls on both conditions of the verbal memory task and had more intrusions from previous lists in the verbal single task. There was no significant difference between groups in either item or order memory, but in parkinsonians the scores on order memory decreased with advancing illness. It is concluded that patients with Parkinson's disease do not have a general inability to cope with concurrent task demands, but that the results can be interpreted as indicating a weakness of certain aspects of the attentional control of cognitive function.

Analysis of Variance↗
PubMed1990

Recency-primacy recognition in Parkinson's disease.

Early parkinsonian patients and matched controls were tested with a newly designed, short recency-primacy recognition task. Parkinsonian patients showed a significant impairment of recency recognition which could neither be explained by deficits in intelligence, attention, and content memory nor by depression.

Aged↗
PubMed1990

Cerebral correlates of imagining colours, faces and a map--II. Negative cortical DC potentials.

Cortical activation patterns as measured by negative shifts of the scalp-recorded cortical steady potential ("DC shifts") were assessed in 28 normal subjects during imagining colours, faces, and a spatial map. Imaging resulted in sustained negative DC shifts at temporal, parietal and particularly at occipital sites. The topographic distributions of such DC shifts was modulated as a function of whether spatial or visual imagery was performed. During imaging the spatial map, a parietal maximum was observed, as opposed to a distribution in favour of temporal and occipital sites during imagining faces and colours. Results suggest a neuroanatomical dissociation between visual and spatial imagery. Since a similar visual-spatial dichotomy exists in perception, the finding is interpreted as further evidence of a shared cerebral substrate for images and percepts. The results are discussed in conjunction with the joint blood flow study.

Adult↗
PubMed1989

The cerebral localization of neuropsychological impairment in Alzheimer's disease: a SPECT study.

Twenty-three patients with a clinical diagnosis of Alzheimer's disease were examined with a set of neuropsychological tests and with 99mTc-hexamethyl-propyleneamineoxime (HMPAO) single photon emission computed tomography (SPECT). Correlations between test results and indices of regional HMPAO distribution were analysed by multidimensional scaling (MDS). Test results covaried positively with relative HMPAO uptake of frontal, inferior parietal and superior temporal regions but not, or in a negative way, with the remainder of the regions. When only positive correlations were analysed, MDS suggested two dimensions of organization: one was related to a dichotomy between frontal and temporo-parietal regions. The relationship of test results to this dimension was largely consistent with common neuropsychological knowledge. A second, less stringent dimension of organization opposed right and left hemisphere regions. The ordering of test results with respect to this dimension was only partly consistent with what is known about the lateralization of neuropsychological deficits from the study of localized brain lesions. The possibility is considered that these inconsistencies may reflect the effect of disproportionally severe involvement of extended cortical systems which modulates the sequels of localized brain damage.

Aged↗
PubMed1989

Regional cerebral blood flow patterns in visual imagery.

Regional cerebral blood flow patterns were investigated by means of single photon emission computerized tomography in subjects who solved cognitive tasks which either did or did not require the use of visual imagery. In a first experiment judging the correctness of visual imagery sentences like "a grapefruit is bigger than an orange" led to increases of regional activity in inferior temporal and in the left inferior-occipital region when compared to blood flow patterns elicited by judgements about low imagery sentences or by responding differentially to "yes" and "no". Motor imagery sentences did not cause such an increase. In a second experiment a condition in which visual images were used for counting the corners of letters was compared to a condition in which subjects internally rehearsed the alphabet. The only difference concerned the inferior frontal regions which showed higher activity in rehearsing the alphabet. However, activity in inferior temporal and inferior occipital regions showed a positive correlation to the self-rated vividness of the visual images in the corner counting condition. The results of both experiments yield converging evidence that visual imagery is selectively related to activity of inferior-temporal and occipital regions. They thus support the hypothesis that the cerebral correlate of visual imagery is different from that of non-imaginal thinking.

Adult↗
PubMed1989

Cerebral correlates of imagining colours, faces and a map--I. SPECT of regional cerebral blood flow.

The distribution of regional cerebral blood flow (rCBF) was assessed by single photon emission computerized tomography (SPECT) in subjects during a resting state and during imagining either colours or faces or a route on a map. Twelve out of 30 subjects reported the spontaneous occurrence of mental visual images during the resting state. In these subjects flow in both orbitofrontal regions was higher than in those subjects who had not experienced spontaneous imagery. Voluntary imagery led to an increase of regional flow indices in basal temporal regions of both hemispheres and to a rightwards shift of global hemispheric asymmetry. The local changes were distinctly more marked with faces than with any of the other two stimuli. Imagining faces was also the only condition that led to an increase of activity in the left inferior occipital region which has been suggested by previous studies as being a crucial area for visual imagery. It is concluded that the observed differences of rCBF patterns between imagery conditions are related to the amount of information conveyed by the mental image. In contrast to the results of a companion study on DC-shifts accompanying imagery there was no effect of the visual versus spatial character of the images.

Adult↗
PubMed1989

The ability of patients with brain damage to generate mental visual images.

The ability to form mental visual images was investigated in normal controls, patients with localized brain damage, and patients with Parkinson's disease. Verbal and visuospatial imagery tasks were compared with tasks in the same modality that did not demand the formation of visual images. In the verbal part, memorizing of word pairs was tested for abstract words, concrete words without imagery instruction, and concrete words with imagery instruction. In the visuospatial part, three tests required the evaluation of spatial features of imagined letters. In one of them mental rotations had to be performed in the exploration of the imagined stimulus. The visuospatial control tasks tested the ability to judge the position of perceived dots and mentally to rotate a seen mannekin. The pattern of results was determined mainly by the differential sensitivity of visuospatial and verbal tasks to right and left brain damage, respectively. Multidimensional scaling of correlations between test results did not show a close relationship between the results of verbal and visuospatial imagery tasks, but suggested that brain damage affected visuospatial imagery tasks differentially from visuospatial control tasks. Analysis of single cases showed that patients with lesions of the left temporo-occipital region failed to benefit from the imagery instruction in the memorizing of concrete words. These patients could nonetheless solve correctly the visuospatial imagery tasks. Possibly this dissociation is due to differences in the amount or the quality of information conveyed by the visual images rather than to the verbal or visuospatial mode of processing to which the images are subjected.

Adolescent↗
PubMed1988

[Prognosis and documentation of the disease course in severe craniocerebral injuries].

35 survivors of severe head injury were consecutively admitted to the Neurological Department, University of Vienna for early rehabilitation. The outcome after a mean observation periods of 19 months was compared with clinical signs (best motor response, pupillary light reaction, pupil size) in the acute stage. The clinical signs were graded semiquantitatively. The outcome was assessed using the Glasgow Outcome Scale and compared with alternatives, the Karnofsky Performance Status and a self-designed neuropsychological rating scale. Both indexes appeared to possess certain advantages which included additional information and sensitivity to change. A significant correlation was established between the long-term outcome after severe head injury on the one hand and the "best motor response" and changes in pupillary light reaction in the acute stage on the other hand. However, the clinical parameter of pupil size in the acute stage does not provide a prognostic indicator of the disability status at the end of the observation period. There was good agreement between the outcome scores derived by means of the 3 rating scales. Solely with respect to the items "orientation and memory function" and "emotions" of the neuropsychological rating scale was no significant correlation obtained with the clinical sign "best motor response" in the acute stage. Our results indicate that it seems possible to assess the outcome after severe head injury not only be means of the widely-adopted Glasgow Outcome Scale, but also using the Karnofsky Performance Status and our neuropsychological rating scale without any marked loss of reliability. The clinical signs - "best motor response" and pupillary light reaction - are excellent prognostic indicators of the long-term outcome after severe head injury.

Adolescent↗
PubMed1988

Structural brain correlates of anterograde memory deficits in multiple sclerosis.

Progressive decline of anterograde memory functions has been increasingly recognized as a frequent symptom in chronic multiple sclerosis. In order to investigate the brain structures involved, magnetic resonance imaging was performed in 20 patients. Neuropsychological assessment included the WAIS and WMS subtests information, picture completion, similarities, digit span, logical memory, and paired associate learning. All patients with severely impaired memory functions (n = 5) showed bilateral lesions in the medial temporal lobe, whereas in those patients with moderate (n = 10) or no measurable impairment of memory testing (n = 5) either no lesions were seen in the medial temporal lobes or these lesions were restricted to one side. A post hoc cluster analysis strikingly confirmed these results. The differences could not be related to the age of the patients, the disease duration, or the level of education. Extensive lesions in the white matter of the frontal lobes, thinning and lining of the corpus callosum, and bilateral involvement of the anterior cingulate gyrus had no bearing on the neuropsychological results. These findings indicate that bilateral demyelination in the hippocampal regions is the most likely explanation for the impairment of anterograde memory in such patients.

Adult↗
PubMed1987

Patterns of regional cerebral blood flow related to memorizing of high and low imagery words--an emission computer tomography study.

Patterns of regional cerebral blood flow were investigated in healthy volunteers who were either resting or memorizing meaningless words, abstract nouns, or concrete nouns, the latter being given either with or without an instruction to use visual imagery. Relative regional count rates were subjected to smallest space analysis (SAA) to study the structure of covariations. Memorizing of concrete nouns gave rise to the formation of a continuous correlational subspace which comprised inferior temporal and occipital regions. When concrete nouns were memorized without an imagery instruction the mean hemispheric count rate was higher on the right side, whereas the intentional use of imagery gave rise to a left preponderance. Analysis of correlational structures, however, suggests that in both cases the left hemisphere was predominantly engaged in task solution, and that the difference in hemispheric asymmetries is to be attributed to different modes of interhemispheric collaboration.

Adult↗
PubMed1987

Initial experience with technetium-99m HM-PAO brain SPECT.

Technetium-99m hexamethylpropyleneamineoxime ([99mTc]HM-PAO) brain single photon emission computed tomography (SPECT) was performed with a dual head rotating scintillation camera. Normal tracer distribution and side/side differences of counting rates were obtained in 11 healthy volunteers. Almost stable gray/white matter ratios were found (1.97-2.1) in one normal subject during 2 hr after tracer administration. Eighty-three investigated patients had the following diagnoses (in parentheses is percent of positive findings in each group): cerebral vascular disease 18 (94.4%), epilepsy 23 (82.6%), extrapyramidal disorders 8 (100%), dementia 12 (100%), headache 11 (63.6%), psychiatric disorders 11 (27.3%). In addition, SPECT was performed in 28 male volunteers during motor or visual imagery tasks and a significant increase (p = 0.035) of relative tracer deposition was observed in the left inferior occipital region during visual imagery when compared with motor imagery. The results indicate that [99mTc]HM-PAO SPECT is valuable for demonstrating pathologic and physiologic changes of the brain.

Adult↗