[Study of motor conditioning as a function of laterality].
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Bilateral EEG measures were obtained on 16 high hypnotizable Ss (scores of greater than 8 on the Harvard Group Scale of Hypnotic Susceptibility, Form A, Shor & E. Orne, 1962), while performing hemisphere-specific tasks during hypnosis and a no-hypnosis control condition. Conditions and tasks were presented in counterbalanced order, and Ss served as their own controls. The data call into question the right hemisphere activation interpretation of lateralized brain function during hypnosis; rather, the data suggest a lack of task appropriate activity during hypnosis. The failure to attend to baseline activity measurements and the use of ratios to evaluate interhemispheric lateralization may contribute to potential misinterpretations of data. It is critical that activity changes of the separate hemispheres be taken into account in the interpretative process.
OBJECTIVES: To test the utility of a new, easy to administer instrument for assessing activities of daily living in patients with amyotrophic lateral sclerosis (ALS), to validate its accuracy, and to assess its ability to record disease progression in patients with ALS against other functional scales, quantitative isometric muscle testing, and global assessment scales. DESIGN: Serial assessments of patients who presented to four ALS treatment centers in two multicenter studies. PATIENTS: Study 1 (cross-sectional) evaluated 75 consecutive patients who presented to four ALS treatment centers during a 2-month period. Study 2 (longitudinal) evaluated the progression of 53 patients who were enrolled in a multicenter, phase I-II clinical trial of recombinant human ciliary neurotrophic factor for treatment of ALS. OUTCOME MEASURES: The ALS Functional Rating Scale (ALSFRS) was compared with quantitative myometry and with other measures of daily function in patients with ALS both cross-sectionally and longitudinally. RESULTS: The first study of 75 patients evaluated the internal consistency, the test-retest reliability, and the construct validity of the ALSFRS. Internal consistency and test-retest reliability were high. Patient self-rating of upper- and lower-extremity-dependent tasks were highly correlated with measures of upper- and lower-extremity strength, respectively. Thus, the ALSFRS has good construct validity. In the second study, ALSFRS scores declined in tandem with deterioration in motor and pulmonary function, indicating its sensitivity to change. CONCLUSIONS: The ALSFRS is a useful instrument for evaluation of functional status and functional change in patients with ALS. Its results are in close agreement with objective measures of muscle strength and pulmonary function. The ALSFRS may be used as a screening measure for entry into clinical trials, as a surrogate measure of function in situations in which muscle strength cannot be measured directly, or as an adjunct to myometry.
Various methods have been proposed to calculate a lateralization index (LI) on the basis of functional magnetic resonance imaging (fMRI) data. Most of them are either based on the extent of the activated brain region (i.e., the number of "active" voxels) or the magnitude of the fMRI signal change. The purpose of the present study was to investigate the characteristics of various variants of these approaches and to identify the one that yields the most robust and reproducible results. Robustness was assessed by evaluating the dependence on arbitrary external parameters, reproducibility was assessed by Pearson's correlation coefficient. LIs based on active voxels counts at one single fixed statistical threshold as well as LIs based on unthresholded signal intensity changes (i.e., based on all voxels in a region of interest) yielded neither robust nor reproducible laterality results. Instead, the lateralization of a cognitive function was best described by "thresholded" signal intensity changes where the activity measure was based on signal intensity changes in those voxels in a region of interest that exceeded a predefined activation level. However, not all other approaches should be discarded completely since they have their own specific application fields. First, LIs based on active voxel counts in the form of p-value-dependent lateralization plots (LI=LI(p)) can be used as a straightforward measure to describe hemispheric dominance. Second, LIs based on active voxel counts at variable thresholds (standardized by the total number of active voxels) are a good alternative for big regions of interest since LIs based on signal intensity changes are restricted to small ROIs.
OBJECTIVE: This study assessed the relationship between symptoms and cognitive measures at intake and functional outcome 2-8 years later (average 3 years) in first-episode and previously treated schizophrenia patients. METHOD: A composite cognitive score was assessed at intake to determine the influence of cognition on later functional outcome. At intake and follow-up, positive and negative symptoms were assessed with the Scale for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative Symptoms, and affective symptoms were assessed with the Hamilton Depression Rating Scale. Level of function in seven domains (social function, occupational function, independent living, symptom severity, fullness of life, extent of psychiatric hospitalization, and overall level of function) at intake and follow-up was assessed with the Strauss-Carpenter Level of Function scale. The contributions of sex, education, and duration of illness to functional outcome were also examined. RESULTS: The results indicated that symptoms at intake had distinct patterns of prognostic significance for functional outcome in previously treated patients, compared with first-episode patients. In addition, male and female patients differed in the degree to which initial symptoms were correlated with later function. CONCLUSIONS: Initial level of function, symptoms, sex, education, and duration of illness are all important predictors for functional outcome in patients with schizophrenia.
Previous accounts of cerebral dominance in schizophrenic patients have been conflicting. While many studies report decreased patterns of functional laterality in schizophrenic subjects, others report increases or no differences. Conceptual differences in the definition of laterality and its effects on behavior may be a reason for the poor concordance among studies. The present report addresses some of these problems and examines the hypothesis that schizophrenia may be associated with an alteration in normal patterns of functional laterality. In addition, the relationship between patterns of laterality and cognitive functioning was assessed. Twenty-one schizophrenic patients and 24 control subjects, all right-handed, were compared on two neuropsychological batteries, one designed to test cerebral dominance and the other, cognitive performance. Cerebral dominance was measured by two dichotic listening tests (verbal and nonverbal) and three motoric tests. Cognitive ability was assessed with a comprehensive neuropsychological battery. Schizophrenic and control subjects differed significantly in performance on laterality measures, but they did not differ in patterns of functional laterality when performance was taken into account. In addition, it was shown that the relationship between cognitive ability and laterality is complex, with some aspects of laterality appearing to be beneficial to cognitive ability.
We performed quantitative meta-analyses on 65 neuroimaging studies of emotion. In an earlier report (NeuroImage 16 (2002), 331). we examined the effects of induction method, specific emotions, and cognitive demand in emotional tasks. This paper focuses on the effects of emotional valence (positive vs negative and approach vs withdrawal) and gender on regional brain activations, with particular emphasis on hypotheses concerning lateralization of brain function in emotion. Overall, we found no support for the hypothesis of overall right-lateralization of emotional function, and limited support for valence-specific lateralization of emotional activity in frontal cortex. In addition, we found that males showed more lateralization of emotional activity, and females showed more brainstem activation in affective paradigms. The study provides evidence that lateralization of emotional activity is more complex and region-specific than predicted by previous theories of emotion and the brain.
The integrity of the cortical cholinergic input system is necessary for attention performance. This experiment tested hypotheses concerning the lateralized contributions of cortical cholinergic inputs to attention performance by assessing the effects of unilateral lesions of basal forebrain cholinergic neurons on sustained attention performance. Loss of right-hemispheric cortical cholinergic inputs impaired the rats' ability to detect signals but did not affect nonsignal trial performance. Conversely, loss of left-hemispheric cortical cholinergic inputs increased the number of false alarms in nonsignal trials. These data correspond with hypotheses about the mediation of detection processes primarily by right-hemispheric circuits and executive aspects of attention performance by left-hemispheric systems. Cortical cholinergic inputs represent a major component of the brain's lateralized attention systems.
Soft-tissue reconstruction alone cannot obtain normal ankle function in patients with large defects in the area of the lateral malleolus. The authors report a functional reconstructive method for the lateral malleolus, utilized in a male patient whose osteosarcoma in the fibula was resected with surrounding soft tissue. In order to reconstruct the lateral malleolus, the remaining half of the fibula at the knee was removed, and the fibular head was fixed with the tibia at the ankle joint. Ligaments were reconstructed with tendon grafts. Skin and soft-tissue defects were reconstructed with a combined composite flap comprised of a latissimus dorsi myocutaneous flap and a serratus anterior muscle flap. Dead space around the bone graft was filled with the serratus anterior muscle flap that was divided into two portions. The surface was covered with the latissimus dorsi myocutaneous flap. The patient regained almost normal function of the ankle joint. This technique would be a useful functional reconstructive method for patients with large defects in the area of the lateral malleolus.
Historical trends for stillbirth rates in Norway are used to study the possible effect of suboptimal conditions early in life upon later reproductive function. A comparison of the trend for the stillbirth rate and the trend for mortality reveals some clear differences. While the mortality shows a steadily falling trend from the turn of the century, the stillbirth rates show a plateau from 1900-1910 to about 1935. Standardized stillbirth rates are computed from age-specific stillbirth rates (which are available for certain five-year intervals from 1880 onwards), and these rates are used to investigate whether a better correspondence between the trends can be obtained by ascribing the stillborn children to the year of the mother's birth, rather than to the year of the stillbirth. The correspondence appears to be clearly improved by ascribing the stillbirths to the mother's birth year. This observation is discussed in relation to other observations providing information on the importance of conditions during early life on the development and function of the reproductive system.
This article describes a contact-lens method to sustain asymmetry in visual deprivation and the use of this method to test the general hypothesis that asymmetry in input deprivation can shift activation balance in the integrated brain, differentially influencing lateral hemispheric function. Effects of asymmetrical visual deprivation were as predicted on lateral asymmetry of EEG theta, producing more theta over the deprived hemisphere. Cross-modal influence of such visual deprivation was found in the perception of pleasantness of odors. An interaction was found between side of visual deprivation and performance on verbal reasoning and spatial orientation tasks. A line-bisection test of visual attention was not sensitive to the effects. Fatigue as rated on the Profile of Mood States was greatest when the left hemisphere was deprived.
OBJECTIVE: To determine the feasibility of using functional magnetic resonance imaging (fMRI) to detect asymmetries in the lateralization of memory activation in patients with temporal lobe epilepsy (TLE). BACKGROUND: Assessment of mesial temporal lobe function is a critical aspect of the preoperative evaluation for epilepsy surgery, both for predicting postoperative memory deficits and for seizure lateralization. fMRI offers several potential advantages over the current gold standard, intracarotid amobarbital testing (IAT). fMRI has already been successfully applied to language lateralization in TLE. METHODS: fMRI was carried out in eight normal subjects and 10 consecutively recruited patients with TLE undergoing preoperative evaluation for epilepsy surgery. A complex visual scene encoding task known to activate mesial temporal structures was used during fMRI. Asymmetry ratios for mesial temporal activation were calculated, using regions of interest defined in normals. Patient findings were compared with the results of IAT performed as part of routine clinical evaluation. RESULTS: Task activation was nearly symmetric in normal subjects, whereas in patients with TLE, significant asymmetries were observed. In all nine patients in whom the IAT result was interpretable, memory asymmetry by fMRI concurred with the findings of IAT including two patients with paradoxical IAT memory lateralization ipsilateral to seizure focus. CONCLUSIONS: fMRI can be used to detect asymmetries in memory activation in patients with TLE. Because fMRI studies are noninvasive and provide excellent spatial resolution for functional activation, these preliminary results suggest a promising role for fMRI in improving the preoperative evaluation for epilepsy surgery.
Lateral and medial branch of the frog's IXth nerve innervates rostral third and caudal two-thirds of the tongue surface, respectively. The amounts of gustatory signals in these branches differ in proportion to the area they supply.
Although the aging literature suggests that there are many paths to later life adjustment, there have been few empirical attempts to identify different patterns of adaptation, or their relation to adaptive outcome. As a way to identify patterns of socioemotional functioning in later life associated with physical hardiness, a cluster analysis was applied to 11 measures of socioemotional functioning in a large sample (N = 1,085) of older adults (65-86 years). Ten subgroups were extracted, with clusters of individuals being primarily defined by social network variables, religious characteristics, and emotion profiles. Groups were then compared on a measure of physical hardiness. Patterns of adaptation characterized by high levels of negative emotions tended to represent less hardy adaptation, although there were nonetheless some patterns of noteworthy exception. In contrast, however, patterns of adaptation characterized by religiosity were typically associated with greater hardiness. Finally, physical hardiness was not exclusively the province of individuals exhibiting close social networks, with some groups high in connectedness being less likely to report high hardiness.
BACKGROUND AND PURPOSE: Transcranial Doppler sonography (TCD) can guide and complement investigations based on functional magnetic resonance and positron emission tomography imaging by providing continuous information on cerebral perfusion changes correlated to cerebral activation. So far, however, the role of functional TCD has been limited by a lack of sensitivity. METHODS: Here, the authors present an outline of a method that increases the potential of TCD to detect perfusion changes within a vascular territory. Sensitivity on the order of 1% can be achieved by transformation of Doppler envelope curves, which accounts for systemic quasi-periodic and irregular spontaneous blood flow modulations and artificial disturbances related to the recording. A statistical technique is introduced that allows the automatic detection of time periods of significant hemispheric lateralization in evoked flow studies. Furthermore, an index of laterality is defined quantifying the extent of hemispheric dominance during stimulus processing. RESULTS AND DISCUSSION: The analysis technique described in this article has been successfully employed in recent examinations on vision, motor activation, language, language recovery, and other cognitive tasks. CONCLUSION: The novel functional TCD technique permits valid and reproducible assessments of the temporal characteristics of functional hemispheric lateralization.
BACKGROUND: Reflux nephropathy (RN) is a pathophysiological human model of reduced nephron reserve, due to loss of renal mass, but little information exists about the role of urinary endothelin-1 (uET-1) in this disease. The aim of this study was to assess the presence of uET-1-like-immunoreactivity (uET-1L) in RN patients, particularly if lateralized renal damage existed. METHODS: Thirty patients with vescico-ureteral reflux (VUR) and consequent RN, were studied. The presence of VUR was established by voiding cysto-urethrography. RN was assessed and graded by 99mTc-dimercapto-succinic acid scan (DMSA). Renal plasma flow (ERPF) was evaluated by (123)I-Hippuran renal sequential scintigraphy, and glomerular filtration rate (GFR) by creatinine clearance. Forty-five healthy subjects were selected as a control group. uET-1L excretion, in both affected and control groups, was assayed. RESULTS: Mann-Whitney U test showed a significant difference between control and patient groups in both GFR and uET-1L. A good correlation between DMSA grading, single kidney clearance and VUR grade was shown. A significant relationship was also shown between uET-1L and both ERPF and GFR. Patients with RN were divided into two subgroups according to functional damage lateralization. Between the two groups, a significant difference was found only for uET-1L when GFR was applied as a covariate in ANCOVA analysis. CONCLUSION: Our preliminary results confirmed the increase of urinary ET-1L excretion in RN, especially when renal functional injury was lateralized.
The authors present their experience with conservative transmandibular lateral pharyngectomy used for access to oropharyngeal tumours of the buccal cavity. This study was conducted to evaluate both early results and later aesthetic and functional sequelae after a simplified operation using mini-plaques. This surgical route was used for 38 patients since 1985, including 9 for salvage operations. Surgical indications were tumours of the posterior wall of the pharynx (28), the posterior part of the tongue (8), the retromolar tigone (1), the intramaxillary commissure (2) and the pelvi-lingual region (2). Access via the mandibulotomy was always evaluated peroperatively on the basis of the cleavability of the periosteum of the medial mandibular table. Immediate follow-up was uneventful in 74% cases. Post-operative complications included two general decompensations due to the original lesion, four minor local complications (spontaneous by regressive non-unions) and four local complications requiring a second intervention (flap necrosis, 2; orostomy, 2). Five of the complications were directly related to the mandibulotomy, giving an overall rate of 13%; the rates for first intention and salvage surgery were 9% and 18% respectively. Functional capacity was considered excellent in 75% of the cases and the aesthetic results were good in 94%. The satisfactory post-operative course, the low rate of major complications both after first intention and salvage surgery, and the excellent functional and aesthetic results suggest that transmandibular bucco-pharyngectomy should be preferred whenever the state of the cancerous lesion does not require exeresis of the ramus.
Amusia is a condition in which musical capacity is impaired by organic brain disease. Music is in a sense a language and closely resembles speech, both executively and receptively. For musical functioning, rhythmic sense and sense of sounds are essential. Musical ability resides largely in the right (non-dominant) hemisphere. Tests have been devised for the assessment of musical capabilities by Dorgeuille, Grison and Wertheim. Classification of amusia includes vocal amusia, instrumental amnesia, musical agraphia, musical amnesia, disorders of rhythm, and receptive amusia. Amusia like aphasia has clinical significance, and the two show remarkable similarities and often co-exist. Usually executive amusia occurs with executive aphasia and receptive amusia with receptive aphasia, but amusias can exist without aphasia. Severely executive aphasics can sometimes sing with text (words), and this ability is used in the treatment of aphasia. As with aphasia, there is correlation between type of amusia and site of lesion. Thus in executive amusia, the lesion generally occurs in the frontal lobe. In receptive amusia, the lesion is mainly in the temporal lobe. If aphasia is also present the lesion will be in the left (dominant) hemisphere.