Rehabilitation of somatoparaphrenia with misoplegia: insights from a single case-pilot study.

Somatoparaphrenia lacka ownership of a paralyzed limb, i.e., the illusion that one's limbs belong to someone else. Somatoparaphrenia is one of the many forms of body misperceptions. We report a case of somatoparaphrenia with misoplegia, characterized by the absence of anosognosia for hemiplegia and personal neglect, following a surgical operation for left parietal meningioma. The patient received a novel multidisciplinary treatment, including motor rehabilitation training, traditional physiotherapy and robotic rehabilitation using the Hunova Movendo Technology and psychological counseling. At the end of the training, the patient improved in global cognitive functioning, mood, motor abilities, and the perception of herself and her body, reducing the sense of estrangement and repulsion in the lower right limb. Our result showed the importance of a specific neuropsychological assessment in patients with parietal brain lesions and the usefulness of an integrated psychological and motor approach in rehabilitating patients with somatoparaphrenia, primarily when associated with misoplegia.

Dissociation between visuospatial neglect assessment tasks and its neuroanatomical substrates: a case report.

Visuospatial neglect possesses significant heterogeneity in clinical features and neuroanatomical substrates. Behavioral dissociations on different neglect tasks have been reported in the past, and the investigation of their respective anatomical correlates at cortical and, to a lesser degree, subcortical levels has been attempted in stroke studies. We report a patient with a neoplasm occupying the right ventral post-central gyrus and anterior supramarginal gyrus. The patient was admitted preoperatively with dissociation on the performance of neglect tasks, showing clinical deficits in the line bisection task and clock drawing, but not on the cancelation task. The patient underwent an awake craniotomy for tumor excision. Intraoperative visuospatial mapping was employed by applying direct electrical stimulation (DES) to the supramarginal gyrus and the ventral branch of the superior longitudinal fasciculus (SLF III) during the line bisection task. According to our findings, DES was ineffective at the cortical level, but it induced strong rightward bias when applied subcortically at the SLF III. By combining our preoperative and intraoperative anatomical and clinical data, we suggest that the posterior part of the SLF III might have a distinct role in the perceptual component of neglect. Our findings are discussed within the context of previous literature supporting the notion that particular behavioral features of spatial neglect are mediated by different white-matter connections.

Neurological Soft Signs Predict Auditory Verbal Hallucinations in Patients With Schizophrenia.

Neurological soft signs (NSS) are well documented in individuals with schizophrenia (SZ), yet so far, the relationship between NSS and specific symptom expression is unclear. We studied 76 SZ patients using magnetic resonance imaging (MRI) to determine associations between NSS, positive symptoms, gray matter volume (GMV), and neural activity at rest. SZ patients were hypothesis-driven stratified according to the presence or absence of auditory verbal hallucinations (AVH; n = 34 without vs 42 with AVH) according to the Brief Psychiatric Rating Scale. Structural MRI data were analyzed using voxel-based morphometry, whereas intrinsic neural activity was investigated using regional homogeneity (ReHo) measures. Using ANCOVA, AVH patients showed significantly higher NSS in motor and integrative functions (IF) compared with non-hallucinating (nAVH) patients. Partial correlation revealed that NSS IF were positively associated with AVH symptom severity in AVH patients. Such associations were not confirmed for delusions. In region-of-interest ANCOVAs comprising the left middle and superior temporal gyri, right paracentral lobule, and right inferior parietal lobule (IPL) structure and function, significant differences between AVH and nAVH subgroups were not detected. In a binary logistic regression model, IF scores and right IPL ReHo were significant predictors of AVH. These data suggest significant interrelationships between sensorimotor integration abilities, brain structure and function, and AVH symptom expression.

Visuoperceptual processing in children with neurofibromatosis type 1: True deficit or artefact?

Impairments in visuoperceptual processing have long been considered a hallmark deficit of individuals with Neurofibromatosis type 1 (NF1). However, it is unclear which specific visuoperceptual subprocesses are impaired and whether impairments on these tasks really result from visuoperceptual impairments or rather from confounding factors like Executive Functioning (EF) impairments, lower intelligence (IQ) and/or co-occurring symptoms of Autism Spectrum Disorder (ASD). To answer these questions, we administered four visuoperceptual tasks and two control tasks in 39 children with NF1, 52 typically developing children and 52 children with ASD (8-18 years), all matched for age and gender. Furthermore, EF, IQ, and symptoms of ASD were assessed. Children with NF1 displayed intact visual form discrimination and intact information integration along the dorsal visual pathway. Moreover, their reduced performance on a task requiring integration of information along the ventral visual stream and their more detail-oriented processing style appeared to result from confounding EF impairments and not from visuoperceptual impairments per se. The co-occurring ASD symptoms and lower IQ of the children with NF1 did not impact substantially upon their visuoperceptual performance. These findings point to the large impact of EF impairments on the performance of visuoperceptual task and suggest that individuals with NF1 show intact visual form discrimination, intact visual integration, and typical visual processing style when potential confounding factors are controlled for. This may have large repercussions for the interpretation of other findings on visuoperceptual processing in individuals with NF1. © 2017 Wiley Periodicals, Inc.

Linking optic radiation volume to visual perception in schizophrenia and bipolar disorder.

People with schizophrenia typically show visual processing deficits on masking tasks and other performance-based measures, while people with bipolar disorder may have related deficits. The etiology of these deficits is not well understood. Most neuroscientific studies of perception in schizophrenia and bipolar disorder have focused on visual processing areas in the cerebral cortex, but perception also depends on earlier components of the visual system that few studies have examined in these disorders. Using diffusion weighted imaging (DWI), we investigated the structure of the primary sensory input pathway to the cortical visual system: the optic radiations. We used probabilistic tractography to identify the optic radiations in 32 patients with schizophrenia, 31 patients with bipolar disorder, and 30 healthy controls. The same participants also performed a visual masking task outside the scanner. We characterized the optic radiations with three structural measures: fractional anisotropy, mean diffusivity, and tract volume. We did not find significant differences in those structural measures across groups. However, we did find a significant correlation between the volume of the optic radiations and visual masking thresholds that was unique to the schizophrenia group and explained variance in masking performance above and beyond that previously accounted for by differences in visual cortex. Thus, individual differences in the volume of the optic radiations explained more variance in visual masking performance in the schizophrenia group than the bipolar or control groups. This suggests that individual differences in the structure of the subcortical visual system have an important influence on visual processing in schizophrenia.

Functional reorganization of the attentional networks in low-grade glioma patients: a longitudinal study.

Right brain damage often provokes deficits of visuospatial attention. Although the spatial attention networks have been widely investigated in stroke patients as well as in the healthy brain, little is known about the impact of slow growing lesions in the right hemisphere. We here present a longitudinal study of 20 patients who have been undergoing awake brain surgery with per-operative line bisection testing. Our aim was to investigate the impact of tumour presence and of tumour resection on the functional (re)organization of the attention networks. We assessed patients' performance on lateralized target detection, visual exploration and line bisection before surgery, and in the acute and post-acute operative phases after surgery. Clear evidence for transient neglect signs was observed in the acute post-operative phase, although full recovery had invariably occurred in all patients. The resection of the right angular gyrus was associated with transient neglect-like symptoms in all tasks, whereas resection of more anterior regions correlated with transient deficits only in visual exploration or detection (but not in line bisection). The attentional networks showed substantial functional recovery. This impressive pattern of recovery is discussed in terms of involvement of the contralateral left hemisphere and of preservation of long-range white matter pathways within the right hemisphere.

Cerebral correlates of visuospatial neglect: a direct cerebral stimulation study.

OBJECTIVE: To assess the role of the superior longitudinal fascicle, the inferior fronto-occipital fascicle, and the posterior parietal lobe in visuospatial attention in humans during awake brain surgery. EXPERIMENTAL DESIGN: Seven patients with hemispheric gliomas (six in the right hemisphere) entered the study. During surgery in asleep/awake anesthesia, guided by Diffusion Tensor Imaging Fiber Tractography, visuospatial neglect was assessed during direct electrical stimulation by computerized line bisection. PRINCIPAL OBSERVATIONS: A rightward deviation, indicating left visuospatial neglect, was induced in six of seven patients by stimulation of the parietofrontal connections, in a location consistent with the trajectory of the second branch of the superior longitudinal fascicle. Stimulation of the medial and dorsal white matter of the superior parietal lobule (corresponding to the first branch of the superior longitudinal fascicle), of the ventral and lateral white matter of the supramarginal gyrus (corresponding to the third branch of the superior longitudinal fascicle), and of the inferior occipitofrontal fasciculus, was largely ineffective. Stimulation of the superior parietal lobule (Brodmann's area 7) caused a marked rightward deviation in all of the six assessed patients, while stimulation of Brodmann's areas 5 and 19 was ineffective. CONCLUSIONS: The parietofrontal connections of the dorso-lateral fibers of the superior longitudinal fascicle (i.e., the second branch of the fascicle), and the posterior superior parietal lobe (Brodmann's area 7) are involved in the orientation of spatial attention. Spatial neglect should be assessed systematically during awake brain surgery, particularly when the right parietal lobe may be involved by the neurosurgical procedure.

Aspectos clínicos y modelos teóricos en el Síndrome de Neglect / Clinicalaspects and theoretical models in Neglect Syndrome

En este trabajo se revisa y discute el síndrome de neglect considerando diferentes modelos teóricos explicativos; de dirección atencional, de asimetrías hemisféricas cerebrales, del sesgo atencional o el modelo de atención selectiva. Se consideran los aspectos cognitivos, emocionales y neuroconductuales. El Síndrome de Neglect generalmente es consecuencia de un accidente cerebrovascular, afecta al hemisferio cerebral derecho y señala directamente al lóbulo parietal. Este es el resultado de una definición anatómica vasta más que una unidad fisiológica o funcional. El síndrome se manifiesta por déficits en la atención perceptiva y en la respuesta a estímulos presentados en el hemicampo contralesional. Es un síndrome heterogéneo. Pese a la preponderancia de las teorías de déficits atencionales, las explicaciones de déficits perceptivos y de representación del espacio están presentes. Son variaciones del síndrome la heminatención, la extinción, la hemicinesia y el neglect hemiespacial. Se resalta la importancia de incluir los aspectos emocionales y neuroconductuales junto con los cognitivos y la rehabilitación motora en el proceso de rehabilitación neuropsicológica del síndrome. Son característicos los síntomas de anosognosia, extinción, desinhibición de conducta, conducta de utilización o la falta de afecto. En cuanto a la recuperación y a cómo ocurre esta, se discuten varias explicaciones alternativas y se apunta el papel de la motivación como factor importante en el éxito de los tratamientos.

This paper reviews the syndrome Neglect considering different theoretical models: attentional direction; of cerebral hemispheric asymmetry, attentional bias, selective attention model. The cognitive, emotional and neurobehavioral characteristics are high lighted. Neglect syndrome usually results from a stroke that affects the right cerebral hemisphere and points directly to the parietal lobe. This is the result of an extensive anatomical definition more than that one functional unit or physiological. The syndrome is manifested by deficits in attention and perceptual responses to stimuli presented in the contralesional hemispace. Neglect is a heterogeneous syndrome. Despite the preponderance of theories of the attentional deficit, explanations of perceptual deficits and representation of space are present. The syndrome manifestations are the heminatención, the extinction, the hemispatial hemicinesia and the neglect. They are very important the emotional aspects as the cognitive, neurobehavioral and motor rehabilitation, in the neuropsychological rehabilitation process of syndrome. Symptoms of anosognosia, extinction, behavioral disinhibition, and the utilization behavior or lack of affection are the most prominent in the syndrome. In terms of recovery, how to happen this? We discuss several alternative explanations and the role of motivation as an important factor in the success of treatments.

Neurophysiological investigation of idiopathic acquired auditory-visual synesthesia.

We present a case of acquired auditory-visual synesthesia and its neurophysiological investigation in a healthy 42-year-old woman. She started experiencing persistent positive and intermittent negative visual phenomena at age 37 followed by auditory-visual synesthesia. Her neurophysiological investigation included video-EEG, fMRI, and MEG. Auditory stimuli (700 Hz, 50 ms duration, 0.5 s ISI) were presented binaurally at 60 db above the hearing threshold in a dark room. The patient had bilateral symmetrical auditory-evoked neuromagnetic responses followed by an occipital-evoked field 16.3 ms later. The activation of occipital cortex following auditory stimuli may represent recruitment of existing cross-modal sensory pathways.

Ophthalmic impairment or higher-order visual deficit? Posterior cortical atrophy: a case report.

A 64-year-old man (GK) was referred to our memory clinic because of progressive memory and concentration problems. His symptoms had started 3 years earlier with gradually increasing visual problems for which no ophthalmologic explanations could be found. Neuropsychological assessment with detailed examination of the visuoperception revealed striking impairments in the higher-order visual functions, leading to a probable diagnosis of posterior cortical atrophy (PCA). The results of magnetic resonance imaging and cerebrospinal fluid examination supported the diagnosis. PCA is considered the posterior variant of Alzheimer's disease that typically presents with problems in visuoperception or, less frequent, apraxia. Despite its clear clinical features, the diagnosis of PCA is often delayed because of the focus on ophthalmologic examination. In this case report, the diagnosis of PCA in a 64-year-old man was not considered until further neuropsychological decay was evident. We argue that screening of higher-order visual functions can significantly contribute to an early diagnosis and treatment of PCA.

Electrostimulation mapping of spatial neglect.

BACKGROUND: Cortical and subcortical electrostimulation mapping during awake brain surgery for tumor removal is usually used to minimize deficits. OBJECTIVE: To use electrostimulation to study neuronal substrates involved in spatial awareness in humans. METHODS: Spatial neglect was studied using a line bisection task in combination with electrostimulation mapping of the right hemisphere in 50 cases. Stimulation sites were identified with Talairach coordinates. The behavioral effects induced by stimulation, especially eye movements and deviations from the median, were quantified and compared with preoperative data and a control group. RESULTS: Composite and highly individualized spatial neglect maps were generated. Both rightward and leftward deviations were induced, sometimes in the same patient but for different stimulation sites. Group analysis showed that specific and reproducible line deviations were induced by stimulation of discrete cortical areas located in the posterior part of the right superior and middle temporal gyri, inferior parietal lobe, and inferior postcentral and inferior frontal gyri (P < .05). Fiber tracking identified stimulated subcortical areas important to spare as sections of fronto-occipital and superior longitudinal II fascicles. According to preoperative and postoperative neglect battery tests, the specificity and sensitivity of intraoperative line bisection tests were 94% and 83%, respectively. CONCLUSION: In humans, discrete cortical areas that are variable in location between individuals but mainly located within the right posterior Sylvian fissure sustain visuospatial attention specifically toward the contralateral or ipsilateral space direction. Line bisection mapping was found to be a reliable method for minimizing spatial neglect caused by brain tumor surgery.

Lumbar microdiscectomy in pediatric patients: a large single-institution series.

OBJECT: Lumbar disc herniation is a rare but significant cause of pain and disability in the pediatric population. Lumbar microdiscectomy, although routinely performed in adults, has not been described in the pediatric population. The objective of this study was to determine the surgical results of lumbar microdiscectomy in the pediatric population by analyzing the experiences at Children's Hospital Boston over the past decade. METHODS: A series of 87 consecutive cases of lumbar microdiscectomy performed by the senior author (M.R.P.) from 1999 to 2008 were reviewed. Presenting symptoms, physical examination findings, and preoperative MR imaging findings were obtained from medical records. Immediate operative results were assessed including operative duration, blood loss, length of stay, and complications, along with long-term outcome and need for repeat surgery. RESULTS: This series represents the first surgical series of pediatric microdiscectomies. The mean patient age was 16.6 years (range 12-18 years) and 60% were female. The preoperative physical examination results were notable for motor deficits in 26% of patients, sensory changes in 41%, loss of deep tendon reflex in 22%, and a positive straight leg raise in 95%. Conservative management was the first line of treatment in all patients and the mean duration of symptoms until surgical treatment was 12.2 months. The mean operative time was 110 minutes and the mean postoperative length of stay was 1.3 days. Complications were rare: postoperative infection occurred in 1%, postoperative CSF leak in 1%, and new postoperative neurological deficits in 1%. Only 6% of patients needed repeat lumbar surgery and 1 patient ultimately required lumbar fusion. CONCLUSIONS: The treatment of pediatric lumbar disc herniation with microdiscectomy is a safe procedure with low operative complications. Nuances of the presentation, treatment options, and surgery in the pediatric population are discussed.

Clear cell meningioma presenting as rapidly deteriorating visual field and acuity during pregnancy.

Clear cell meningioma is a rare histological phenotype of meningioma. It has an atypical grade II World Health Organization classification due to a high recurrence rate. This report documents the rapid deterioration of visual field and acuity in a pregnant 32-year-old woman and the successful post-operative resolution of symptoms. We review the literature about this rare disease and identify clinical and pathological features unique to this patient.

Seizures in corticobasal degeneration: a case report.

Seizures are relatively common in Alzheimer disease (AD) and other neurodegenerative disorders. To our knowledge, however, there have been no reports of seizures associated with corticobasal degeneration (CBD). We describe a patient with brain biopsy features suggestive of CBD whose course was complicated by complex partial seizures with secondary generalization. Thus, the occurrence of seizures in a patient with dementia should not exclude the diagnosis of CBD.

Preliminary clinical study in patients with hemispatial neglect after stroke by neglect test battery and 99mTc-ECD single-photon emission computed tomography.

OBJECTIVE: To explore the presence, clinical characteristics, anatomical foci in image and mechanism of hemispatial neglect (HSN), neglect test battery and single-photon emission computed tomography (SPECT) regional cerebral blood flow (rCBF) imaging were performed on patients with stroke. METHODS: Thirty dextromanual patients who were diagnosed as having unilateral stroke clinically were recruited. A neglect test battery including line bisection test, star cancellation test and drawing test was performed on the subjects. The severity of neglect was measured on neglect tests. The lowest rCBF, the range with decreased rCBF, number of the foci with decreased rCBF, the flow deficit size and the total number of pixels in the foci were measured on SPECT rCBF imaging. RESULTS: Twenty-five patients were diagnosed as having HSN by the neglect test battery. Contralateral neglect (CN) and ipsilateral neglect (IN) were observed in both right and left hemisphere strokes. On SPECT imaging, the patients with neglect had decreased rCBF in the frontal cortex most often; followed by the parietal, occipital and temporal cortices; and basal ganglia and thalamus in some cases. The patients who had two or more regions damaged showed neglect more often and severity. The correlation coefficients between rCBF in the foci, the decreased percentage of rCBF of the foci and the severity of neglect were -0.119 (P>.05) and 0.221 (P>.05). The correlation coefficients between the range, number of foci, the flow deficit size, the total number of pixels of the foci and the severity of neglect were 0.537 (P<.05), 0.493 (P<.05), 0.561 (P<.05), 0.466 (P<.05), respectively. No difference between CN and IN on SPECT images reached statistical significance. CONCLUSIONS: The severity of neglect did not correlate with rCBF and the decreased percentage of rCBF in the foci, while it was significantly correlated with the range, number of foci, the flow deficit size and the total numbers of pixels of the foci significantly. And the patients with CN and IN did not show any difference in the presence of HSN, the manifestation on the neglect test battery and SPECT images. HSN showed damage on multiple sites, with combined damages resulting in more severe neglect.

Cognitive visual dysfunctions in preterm children with periventricular leukomalacia.

AIM: Cognitive visual dysfunctions (CVDs) reflect an impairment of the capacity to process visual information. The question of whether CVDs might be classifiable according to the nature and distribution of the underlying brain damage is an intriguing one in child neuropsychology. METHOD: We studied 22 children born preterm (12 males, 10 females; mean age at examination 8y, range 6-15y; mean gestational age 30wks, range 28-36wks) with periventricular leukomalacia, spastic diplegia, normal intelligence (mean Full-scale IQ 84; mean Verbal IQ 97; mean Performance IQ 74), and normal visual acuity, focusing on higher visual functions. Brain magnetic resonance images (MRI) were analysed to establish the presence of lesions along the primary optic pathway, in the occipitoparietal and occipitotemporal regions. RESULTS: Most children displayed an uneven cognitive profile, with deficits in visual object recognition, visual imagery, visual-spatial skills, and visual memory, and sparing of visual associative abilities, non-verbal intelligence, and face and letter recognition. Conventional brain MRI did not document major alterations of parietal and temporal white matter, or cortical alteration of areas involved in visual associative functions. INTERPRETATION: We suggest a widespread involvement of higher visual processing systems, involving both the ventral and dorsal streams, in preterm children with periventricular leukomalacia. The lack of major alterations on conventional MRI does not exclude the possibility of malfunctioning of higher visual processing systems, expressing itself through discrete CVDs. Possible mechanisms underlying these neuropsychological deficits are discussed.

Visual neglect.

PURPOSE OF REVIEW: Left visual neglect is a frequent and dramatic consequence of right hemisphere lesions. Diagnosis is important because behavioural and pharmacological treatments are available. Furthermore, neglect raises important issues concerning the brain mechanisms of consciousness, perception and attention. RECENT FINDINGS: Recent behavioural findings and new techniques, such as transcranial magnetic stimulation, direct cortical and subcortical stimulation during brain surgery, and diffusion tensor imaging tractography, have provided evidence relevant to the debate concerning the functional mechanisms and the anatomical bases of neglect. SUMMARY: Several component deficits appear to interact in producing different forms of neglect. Rather than lesions at single cortical levels, dysfunction of large-scale brain networks, often induced by white matter disconnection, may constitute the crucial antecedent of neglect signs.

The Corridor Task: a simple test of lateralised response selection sensitive to unilateral dopamine deafferentation and graft-derived dopamine replacement in the striatum.

In this experiment, we report a novel drug-free behavioural test of lateralised neglect which is sensitive to unilateral dopamine-denervating lesions and subsequent graft-derived striatal dopamine replacement. For the task, white plastic lids containing sugar pellets were placed along the left and right sides of the floor of a long narrow corridor at regular intervals. Hungry female Sprague-Dawley rats were placed individually into the corridor where they were allowed to make up to 20 pellet retrievals. The number of retrievals each rat made from its left and right sides was counted. Complete mesencephalic or partial nigrostriatal lesions were induced by injection of 6-hydroxydopamine into the medial forebrain bundle or striatum, respectively. Both lesions induced a pronounced ipsilateral retrieval bias in the task. Five weeks after lesion surgery, half of the rats from each lesion group were given E14 ventral mesencephalic cell suspension transplants into the denervated striatum, and were then re-tested in the Corridor Task 5 and 10 weeks later. There was no amelioration of the side bias in rats with medial forebrain bundle lesions. In contrast, in nigrostriatal-lesioned rats, the graft significantly reduced the lesion-induced ipsilateral bias. We conclude that the Corridor Task is a sensitive test of lateralised sensorimotor response selection, and is suitable for assessing deficits and recovery associated with lesions and grafts within the nigrostriatal system.