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At least 253 records · Page 14Linked to original sources
PubMed1998

A 67-year-old woman with polymyalgia rheumatica and left hemispatial neglect.

A 67-year-old woman with a diagnosis of polymyalgia rheumatica presented initially with periods of confusion and incontinence. A CT scan of the brain was normal and she was treated with tapering doses of corticosteroids and clinical improvement. After a brief period off steroids, the patient presented with a progressive dementia, left-sided clumsiness, gait disturbances and left hemispatial neglect. An MRI at this time demonstrated a large area of edema over the right parietal lobe and intense cortical enhancement. A chest CT demonstrated multiple nodules. Biopsies of the lung and brain failed to identify any infectious organisms or malignant tissue. The leptomeningeal biopsy revealed multiple granulomatous areas with central necrosis and hystiocytic cells consistent with idiopathic hypertrophic pachy-meningitis.

Aged↗
PubMed1997

Efferent projections of a physiologically characterized region of the inferior colliculus of the young adult CBA mouse.

The present investigation is part of an ongoing series of studies aimed at discerning the neural bases of presbycusis. Presbycusis is a sensory perceptual disorder involving loss of high-pitch hearing and reduced ability to process biologically relevant acoustic signals in noisy environments. The purpose of the present experiment was to delineate the efferent projections of a functionally characterized region of the dorsomedial inferior colliculus (IC, auditory midbrain) in young, adult CBA mice. The CBA strain's progressive loss of hearing over its lifespan approximates many aspects of the mild-to-moderate hearing loss experienced by a significant number of humans suffering from presbycusis. Focal, iontophoretic injections of HRP were made in the 18-24 kHz region of dorsomedial IC of the CBA strain following physiological mapping experiments. Serial sections were reacted with a chromagen, counterstained and examined for anterogradely labeled fibers and boutons. Efferent projections were observed ipsilaterally in: medial and ventral divisions of the medial geniculate body (MGB); middle layers of the superior colliculus; central gray; and external nucleus (E), dorsal cortex (DC) and central nucleus of IC. Contralaterally, labeled fibers and boutons were seen in the IC at a location homologous to the injection site, as well as in E and DC. A small projection was noted in contralateral MGB. These findings in young, adult mice with normal hearing can now serve as a baseline for similar experiments being conducted in mice and animals of other species of older ages and with varying degrees of hearing loss.

Animals↗
PubMed1998

Cue dependent right hemineglect in schizophrenia: a kinematic analysis.

OBJECTIVES: Schizophrenia may result from disturbed attentional processes and/or defective internal cueing. Attention for subsequent action within a cued movement task was therefore studied, testing specific hypotheses of hemispheric dysfunction and of impaired interhemispheric communication. METHOD: Fifteen patients with schizophrenia and 15 matched controls were either cued or uncued when moving a pen to a target on their right or left side with their right or left hand. Pen tip position was sampled at 200 Hz on a WACOM SD420 graphics tablet for subsequent kinematic analysis. RESULTS: Patients with schizophrenia were slower initiating rightwards movements without a cue. Patients also exhibited reduced abductive/adductive differences in the shape of their movement trajectories, implying differences in interhemispheric communication. CONCLUSIONS: It is speculated that schizophrenia is a form of cue dependent right hemineglect.

Adolescent↗
PubMedDate not supplied

Impaired initiation but not execution of contralesional saccades in hemispatial neglect.

Patients with unilateral neglect are impaired at making saccades to contralesional targets. Whether this problem arises from a deficit in perception, in planning the saccade or in executing the eye movement or some combination thereof remains unclear. We measured several variables related to the initiation and execution of saccades in an experiment which crossed two factors: target side (left, right) and direction of saccade (leftwards, rightwards). Relative to control subjects, patients with left-sided neglect were impaired in planning but not executing the contralesional saccade; while the latency to move their eyes following the onset of the target was increased, the duration and velocity to reach the target were normal. In addition, there were also no directional differences for saccades that were hypometric or inaccurate in the patients, further ruling out an execution impairment. Interestingly, this directional initiation deficit was exaggerated for leftward saccades to left targets, compared with all other conditions. We suggest that the disadvantage for contralesional saccades in neglect patients is attributable to a deficit not only in perceiving contralateral targets but also in planning leftward saccades. Once the saccade is initiated, however, execution apparently proceeds unimpaired.

Adult↗
PubMed2005

Persisting reversed clock syndrome.

BACKGROUND: The reversed clock phenomenon results in the transposition of objects from one side to another. Its major manifestation consists in the reversal of clock numbers in clock-drawing test. It could be due to a stroke disrupting attentional cerebral network. This phenomenon usually regresses in a few days. OBJECTIVE: To report a case of reversed clock phenomenon with disorders of space representation that did not regress spontaneously. DESIGN: Case report. PATIENT: A 67 year-old woman was referred due to headaches associated with gait disorder, visual field deficit and disturbance of space representation. RESULTS: Magnetic resonance imaging demonstrates two right cerebral infarcts mainly localized in the parieto-occipital region. A week after her stoke, clinical testing confirms a reversed clock phenomenon. The patient placed the hands of a clock in the opposite direction of what was specified. She got lost at home locating rooms in directions opposite to their real ones. Rehabilitation sessions partially improved these manifestations. CONCLUSION: Although it usually improves in a few days, reversed clock phenomenon can persist longer. Rehabilitation sessions based on localization exercises may be helpful in such situations.

Aged↗
PubMed2000

Loss of left-sided volitional movements caused by a combined lesion of the corpus callosum and right hemisphere:'initiation pseudohemiakinesia'.

We report a right-handed patient who showed a marked loss of unilateral volitional movements of the left limbs after the onset of a cerebral infarction in the combined territories of the right anterior and middle cerebral arteries. The same limbs retained their mobility in acts requiring bilateral sides of the body. This left-sided abnormal behavior resembled motor neglect resulting from lateralized brain damage. Behavioral and neuroradiological findings presented by this patient, however, suggested that callosal disconnection was definitely involved in this symptomatology. We postulate that in this patient, the diseased right hemisphere could no longer initiate movements of the left limbs despite its potential ability to realize them, and that the injured callosum prevented the intact left hemisphere from initiating unilateral voluntary movements of the left limbs. We suggest that this so far undescribed symptomatology be called 'initiation pseudohemiakinesia' in order to be distinguished from other rare forms of unilateral voluntary movements like motor neglect, extinction or directional hypokinesia.

Brain Diseases↗
PubMedDate not supplied

Migraine with aura and right-to-left shunt on transcranial Doppler: a case-control study.

Right-to-left shunt (RLS), usually due to patent foramen ovale, is a well-established risk factor for ischemic stroke in young patients, while the role of migraine as an independent factor is still debated. We evaluated 44 patients suffering from migraine with aura, and compared them with 73 patients younger than 50 with focal cerebral ischemia, and 50 controls, asymptomatic for cerebrovascular disease, and without a history of migraine. All the subjects underwent bilateral transcranial Doppler with injection of contrast medium in an antecubital vein. The test was performed during normal ventilation and during Valsalva maneuver, recording both the middle cerebral arteries and the basilar artery. Criteria for diagnosing RLS was the presence of at least 3 microbubbles within 15 s from injection. Eighteen out of 44 migraine patients (41%) showed RLS, as opposed to 8 of 50 controls (16%) (p < 0.005). Twenty-six out of 73 patients with cerebral ischemia had RLS (35%). We conclude that the prevalence of RLS in patients with migraine with aura is significantly higher than in normal controls, and is similar to the prevalence of RLS in young patients with stroke. These findings could be helpful in understanding the relationship between migraine and stroke.

Adolescent↗
PubMed1991

Lateralized anomalous perceptual experiences in schizophrenia.

Four cases of schizophrenia are described, in which subjects reported anomalous perceptual experiences confined to one visual field, in all cases the left visual field. The pattern, content and laterality of such anomalous perceptions point to the presence of right hemisphere dysfunction in schizophrenia. Further evidence to this effect comes from examining the type of anomalous perceptual experiences reported by subjects with focal lesions in either hemisphere. Those with right hemisphere damage but not those with left hemisphere damage report almost identical experiences to those seen in the 4 schizophrenics described here.

Adult↗
PubMed2005

Functional recovery after hemiplegia in patients with neglect: the rehabilitative role of anosognosia.

BACKGROUND AND PURPOSE: The aim of this study was to verify whether the presence of anosognosia (A) affects the rehabilitative prognosis of hemiplegic subjects with neglect (N). METHODS: This study was carried out on 30 patients with left hemiplegia: 15 patients had neglect (group N) and 15 had neglect and anosognosia (group N+A). Mean age was 68.2+/-6.3 in group N (9 men and 6 women) and 72.1+/-6.4 in group N+A (7 men and 8 women). The average interval from onset of stroke to admission for rehabilitation was 23 and 23.6 days, respectively, in group N and in group N+A. Patients were assessed through the Mesulam test, Bisiach test, Wechsler Adult Intelligence Scale, Fugl-Meyer scale, Functional Independence Measure (FIM), and Rankin scale. RESULTS: Before rehabilitation, cognitive FIM scores of patients of group N were significantly higher than those of group N+A (P=0.001), whereas motor FIM scores and total FIM scores did not differ between the 2 groups. After rehabilitation, cognitive FIM scores (P=0.000) and even motor (P=0.009) and total FIM scores (P=0.000) were statistically higher in group N than in group N+A. Effectiveness (P=0.005) and efficiency (P=0.012) in the motor FIM scores of group N were significantly greater than those of group N+A. Disability was lower in group N (P=0.040). CONCLUSIONS: Our study shows that the presence of anosognosia worsens the rehabilitation prognosis in hemiplegic subjects who also have neglect.

Aged↗
PubMed2005

Ineffectiveness of prism adaptation on spatial neglect signs.

BACKGROUND AND PURPOSE: To evaluate the effect of prism adaptation (PA) on spatial neglect signs. METHODS: Ten patients (hemianopia in 6) and 8 control subjects were included. Tasks were reading single words, nonwords, and a text, bell cancellation, line bisection, and scene drawing, before and after adaptation, with either deviating or neutral prisms. RESULTS: Errors were more frequent in patients but without any specific effect of PA. We found partial improvement at the late sessions, independent of prisms. CONCLUSIONS: We did not confirm the efficacy of PA on spatial neglect.

Adaptation, Physiological↗
PubMed2005

Revisiting previously searched locations in visual neglect: role of right parietal and frontal lesions in misjudging old locations as new.

Right-hemisphere patients with left neglect often demonstrate abnormal visual search, re-examining stimuli to the right while ignoring those to the left. But re-fixations alone do not reveal if patients misjudge whether they have searched a location before. Here, we not only tracked the eye movements of 16 neglect patients during search, but also asked them to click a response button only when they judged they were fixating a target for the very first time. ''Re-clicking'' on previously found targets would indicate that patients erroneously respond to these as new discoveries. Lesions were mapped with high-resolution MRI. Neglect patients with damage involving the right intraparietal sulcus or right inferior frontal lobe ''re-clicked'' on previously found targets on the right at a pathological rate, whereas those with medial occipito-temporal lesions did not. For the intraparietal sulcus patients, the probability of erroneous re-clicks on an old target increased with time since first discovering it; whereas for frontal patients it was independent of search time, suggesting different underlying mechanisms in these two types of patient. Re-click deficits correlated with degree of leftward neglect, mainly due to both being severe in intraparietal cases. These results demonstrate that misjudging previously searched locations for new ones can contribute to pathological search in neglect, with potentially different mechanisms being involved in intraparietal versus inferior frontal patients. When combined with a spatial bias to the right, such deficits might explain why many neglect patients often re-examine rightward locations, at the expense of items to their left.

Adult↗
PubMed1976

The syndrome of autism: a critical review.

The authors review the clinical features and behavioral characteristics of autism; differential diagnosis of the syndrome; clinical, neurophysiological, and biochemical research; and its medical management and treatment. They conclude that autism is a behaviorally defined, specific syndrome that is manifested at birth or shortly thereafter. Its symptoms are expressive of an underlying neuropathophysiological process that affects developmental rate; modulation of perception; language, cognitive, and intellectual development; and the ability to relate. The long-term prognosis is guarded; almost all patients manifest severe symptomatology throughout their lives. Further basic research into the neuropathophysiological process underlying the syndrome is necessary in order to reach the ultimate goal of developing etiologically specific treatment programs.

Age Factors↗
PubMed1978

Phantom bite syndrome.

Despite repeated treatment failures, some individuals seek bite correction from a succession of dentists. Their pathological narcissism focuses on their bite, in a manner reminiscent of phantom limb phenomena. The dentist's diagnosis and treatment are manipulated until the patient claims them a failure and consults another dentist. The author suggests that this behavior represents a defense against paranoia and severe personality disorders.

Adolescent↗
PubMed1999

Reduced design fluency in subclinical obsessive-compulsive subjects.

This study examined the verbal and design fluency abilities of 25 subclinical obsessive-compulsive (OC) subjects and 27 noncompulsive control subjects. As hypothesized, the OC group showed reduced design fluency, and design fluency was also negatively correlated with obsessionality. These results provide further evidence for the involvement of the right corticostriatal systems in the mediation of OC behaviors, extending the findings to individuals with subclinical symptoms.

Adult↗