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33 results on '"Cerebral cortex -- Abnormalities"'

1. HP1-[beta] is required for development of the cerebral neocortex and neuromuscular junctions

Author

Aucott, Rebecca, Bullwinkel, Jorn, Yu, Yang, Shi, Wei, Billur, Mustafa, Brown, Jeremy P., Menzel, Ursula, Kioussis, Dimitris, Wang, Guozheng, Reisert, Ingrid, Weimer, Jorg, Pandita, Raj K., Sharma, Girdhar G., Pandita, Tej K., Fundele, Reinald, and Singh, Prim B.

Subjects
Cerebral cortex -- Growth, Cerebral cortex -- Abnormalities, Neuromuscular junction -- Growth, Proteins -- Identification and classification, Proteins -- Health aspects, Company growth, Biological sciences
Abstract

HP1 proteins are thought to be modulators of chromatin organization in all mammals, yet their exact physiological function remains unknown. In a first attempt to elucidate the function of these proteins in vivo, we disrupted the murine Cbx1 gene, which encodes the HP1-[beta] isotype, and show that the [Cbx1.sup.-/-] null mutation leads to perinatal lethality. The newborn mice succumbed to acute respiratory failure, whose likely cause is the defective development of neuromuscular junctions within the endplate of the diaphragm. We also observe aberrant cerebral cortex development in [Cbx1.sup.-/-] mutant brains, which have reduced proliferation of neuronal precursors, widespread cell death, and edema. In vitro cultures of neurospheres from [Cbx1.sup.-/-] mutant brains reveal a dramatic genomic instability. Our results demonstrate that HP1 proteins are not functionally redundant and that they are likely to regulate lineage-specific changes in hetero-chromatin organization.

Published
2008

2. Electroclinical and imaging findings in ulegyria and epilepsy: a study on 25 patients

Author

Kuchukhidze, G., Unterberger, I., Dobesberger, J., Embacher, N., Walser, G., Haberlandt, E., Gotwald, T., Maier, H., Ortler, M., Felber, S., Bauer, G., and Trinka, E.

Subjects
Cerebral cortex -- Abnormalities, Epilepsy -- Diagnosis, Magnetic resonance imaging -- Usage, Diagnostic imaging -- Usage, Health, Psychology and mental health
Published
2008

3. Abnormal development of the human cerebral cortex: genetics, functional consequences and treatment options

Author

Guerrini, Renzo, Dobyns, William B., and Barkovich, A. James

Subjects
Cerebral cortex -- Abnormalities, Cerebral cortex -- Genetic aspects, Brain -- Abnormalities, Brain -- Care and treatment, Brain -- Genetic aspects, Brain research, Health, Psychology and mental health
Abstract

Genetic studies have identified several of the genes associated with malformations of cortical development which might disrupt each of the main stages of cell proliferation and specification, neuronal migration and late cortical organization. The largest malformation groups, focal cortical dysplasia, heterotopia and polymicrogyria, express different perturbations of these stages and carry a variable propensity for lacking activation, preservation or reorganization of cortical function and for atypical cortical organization. Some patients have obvious neurological impairment, whereas others show unexpected deficits that are detectable only by screening. Drug-resistant epilepsy is frequent but might be amenable to surgical treatment. However, the epileptogenic zone might include remote cortical and subcortical regions. Completeness of resection, a key factor for successful surgery, might be difficult, especially in proximity to eloquent cortex. Surgical planning should be based on assessments of structural imaging and of the major functions relevant to the area in question in any such patient.

Published
2008

5. Patterns of hippocampal abnormalities in malformations of cortical development

Author

Montenegro, M.A., Kinay, D., Cendes, F., Bernasconi, A., Bernasconi, N., Coan, A.C., Li, L.M., Guerreiro, M.M., Guerreiro, C.A.M., Lopes-Cendes, I., Andermann, E., Dubeau, F., and Andermann, F.

Subjects
Cerebral cortex -- Abnormalities, Hippocampus (Brain) -- Research, Hippocampus (Brain) -- Abnormalities, Nervous system -- Abnormalities, Nervous system -- Physiological aspects, Nervous system -- Research, Health, Psychology and mental health
Published
2006

6. Regionally localized thinning of the cerebral cortex in schizophrenia

Author

Kuperberg, Gina R., Broome, Matthew R., McGuire, Philip K., David, Anthony S., Eddy, Marianna, Ozawa, Fujiro, Goff, Donald, West, W. Caroline, Williams, Steven C.R., Kouwe, Andre J.W. van der, Salat, David H., Dale, Anders M., and Fischl, Bruce

Subjects
Cerebral cortex -- Abnormalities, Schizophrenia -- Physiological aspects, Health, Psychology and mental health
Published
2003

7. Deletion of YWHAE in a patient with periventricular heterotopias and pronounced corpus callosum hypoplasia

Author

Mignon-Ravix, Cecile, Cacciagli, Pierre, El-Waly, Bilal, Moncla, Anne, Milh, Mathieu, Girard, Nadine, Chabrol, Brigitte, Philip, Nicole, and Villard, Laurent

Subjects
Cerebral cortex -- Genetic aspects, Cerebral cortex -- Abnormalities, Cerebral cortex -- Research, Corpus callosum -- Genetic aspects, Corpus callosum -- Abnormalities, Corpus callosum -- Research, Health
Published
2010

9. An eight-year-old boy with intractable seizures

Author

Holmes, Gregory L. and Frosch, Matthew P.

Subjects
Seizures (Medicine) -- Causes of, Cerebral cortex -- Abnormalities, Dysplasia -- Diagnosis
Abstract

A child with seizures nonresponsive to medication was diagnosed as having focal cortical dysplasia. Focal cortical dysplasia is abnormal brain cell development, and improvements in imaging technology are finding that it may be the underlying cause of intractable seizures in more children than previously suspected. Epileptic episodes began at age four, and by the time the child was eight, seizures were frequent and uncontrollable with medication. Seizures were focused in the temporal lobe of the brain, which was removed. This cured the seizures. Microscopic analysis of tissue samples from the temporal lobe revealed oversized, abnormally arranged nerve cells, confirming the diagnosis.

Published
1996

10. Evolutional changes of cortical hypometabolism in West's syndrome

Author

Maeda, Norihide, Watanabe, Kazuyoshi, Negoro, Tamiko, Aso, Kosaburo, Ohki, Takashi, Ito, Kengo, and Kato, Takashi

Subjects
Spasms, Infantile, PET imaging, Glucose metabolism -- Physiological aspects, Cerebral cortex -- Abnormalities
Published
1994

11. Focal neuronal migration disorders and intractable partial epilepsy: a study of 30 patients

Author

Palmini, Andre, Andermann, Frederick, Olivier, Andre, Tampieri, Donatella, Robitaille, Yvon, Andermann, Eva, and Wright, Geoffrey

Subjects
Developmental neurology -- Research, Cerebral cortex -- Abnormalities, Epilepsy -- Case studies, Health
Abstract

While the cerebral cortex covers much of the surface of the brain, the cells that comprise the cortex originate in the center, from cells lining the fluid filled ventricles. During embryonic development, new cells migrate from their source within the brain to the cortex. In rare circumstances, this migration is altered and the resulting cerebral cortical structure is malformed. Such neuronal migration disorders (NMDs) have a wide range of severities. Some patients die in infancy or live only a vegetative existence. Others suffer only moderate deficits, which may include mild intellectual deficit or epilepsy. In many cases, epilepsy resulting from an NMD is likely to be refractory to medical treatment. A study was conducted on 30 patients with both intractable epilepsy and evidence of a neuronal migration disorder. These patients displayed a variety of forms of epilepsies and most patients experienced more than one type of seizure. Complex partial seizures, partial motor seizures, and secondary generalized seizures were each experienced by over two-thirds of the patients. Intelligence testing revealed that 44 percent of the patients scored lower than 80 on a standard IQ test. In contrast with epileptic symptoms arising from other origins, among these patients the seizures arose from a broad area of the brain, encompassing more than one lobe in 70 percent of the patients. In the majority of cases, the NMD could not be attributed to any definite cause. However, in some cases, events that might have contributed to the abnormality were identified. For example, in three cases, the mother had been exposed to X-rays in the first trimester of pregnancy. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1991

12. Focal neuronal migration disorders and intractable partial epilepsy: results of surgical treatment

Author

Palmini, Andre, Andermann, Frederick, Olivier, Andre, Tampieri, Donatella, and Robitaille, Yvon

Subjects
Epilepsy, Cerebral cortex -- Abnormalities, Developmental neurology -- Research, Health
Abstract

Neuronal migration disorders (NMDs) are abnormalities of brain structure that result when migrating neurons in embryonic development fail to reach their proper locations. Most often affecting the cerebral cortex, these NMDs may result in epileptic seizures that do not respond to medical treatment. Thirty cases are reported in which intractable partial epilepsy was associated with signs of neuronal migration disorders; the evidence for NMD is usually obtained by magnetic resonance imaging (MRI), which is precise enough to show that some abnormality exists, but insufficient to categorize the abnormality exactly. In the present series of 30 patients, the intractable epilepsy was sufficiently severe to warrant surgical treatment in 26 cases. Based on both the MRI and electroencephalography (EEG) regions of the cerebral cortex responsible for the seizures were mapped out for surgical excision. However, it was not possible to remove all abnormal brain tissue in all cases because the abnormal tissue was quite extensive in some patients. In only four cases was complete excision of the abnormal cortex achieved. Two of these patients enjoyed total freedom from seizures, while the other two achieved good relief as a result of the surgery. In 11 patients, it was possible to remove more than half of the obviously abnormal brain area; many, but not all, of these experienced good relief from seizures. Of the remaining patients, for whom less than 50 percent of the affected brain tissue could be removed, four achieved results which were not good, but which were deemed worthwhile. In the remaining seven patients, only minor benefit was achieved. A comparison of the data obtained by MRI and EEG with the results of the surgery suggest the fraction of the brain lesion visible on MRI that was actually removed was a more important indicator of success than the area of the brain that showed epileptic findings on the EEG. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1991

13. Diffuse cortical dysplasia, or the 'double cortex' syndrome: the clinical and epileptic spectrum in 10 patients

Author

Palmini, A., Andermann, F., Aicardi, J., Dulac, O., Chaves, F., Ponsot, G., Pinard, J.M., Goutieres, F., Livingston, J., Tampieri, D., Andermann, E., and Robitaille, Y.

Subjects
Mental retardation -- Case studies, Brain -- Abnormalities, Dysplasia -- Case studies, Cerebral cortex -- Abnormalities, Epilepsy -- Case studies, Health, Psychology and mental health
Abstract

The brain begins its development as the neural tube, proliferating cells along this tube migrate to take up their proper locations within the developing brain. This results in an 'inside-out' process of development in which new brain cells are formed in the middle of the brain, and migrate out through the brain tissues before they reach their correct location. This process does not always work properly, and several distinct brain abnormalities appear to result from disordered neuronal migration. These disorders can be collectively called neuronal migration disorders( NMDs). One NMD is lissencephaly, in which the brain is smooth, failing to develop the normal pattern of convolutions or gyri. Such patients are profoundly retarded and usually die before two years of age. Another NMD, one with a more mild outcome, is the so-called 'double cortex' syndrome. In this condition, some of the migrating brain cells fail to reach their proper destination on the surface of the brain. These brain cells do not die, but try to fulfill their destiny in the wrong location, beneath the mantle of properly located cortex. In the brains of such patients a cell-rich layer of tissue, or grey matter, can be seen beneath the cerebral cortex, an area in which only myelinated nerve fibers, or white matter, is normally located. It is this second anomalous layer of grey matter that is responsible for the term 'double cortex'. Patients with double cortex are usually retarded, though the syndrome is compatible with a normal lifespan. Patients with double cortex syndrome are commonly affected by epilepsy as well. In the past, double cortex syndrome was observed only at autopsy. The advent of modern imaging techniques has made it possible to identify cases of double cortex syndrome among living patients. Since the presence of double cortex syndrome would affect decisions on the most appropriate treatment for epilepsy in some patients, the indications of double cortex syndrome on magnetic resonance imaging (MRI) or computed tomography (CT) should be recognized. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1991

14. Generalized cortical dysplasia: clinical and pathologic aspects

Author

Kazee, Ann M., Lapham, Lowell W., Torres, Carlos F., and Wang, David D.

Subjects
Dysplasia -- Case studies, Brain -- Histopathology, Cerebral cortex -- Abnormalities, Health
Abstract

Most of the outer surface of the brain consists of cerebral cortex, a thin layer of brain cells and complex interconnections critical to most higher brain functions. Upon gross examination, the cerebral cortex is highly folded in a typical pattern of convolutions called gyri separated by grooves called sulci. Under the microscope, the cerebral cortex is a very highly organized structure consisting of six layers. Cortical dysplasia is a condition in which the normal cellular architecture of the cortex is disturbed by the presence of an increased number of large abnormal neurons. In such cases, the normal six-layered structure is disrupted. Similar large, abnormal neurons may be seen in the white matter underlying the cerebral cortex. It is believed that these neurons represent an abnormality arising in early development and subsequently fail to migrate successfully to their appropriate location as adult brain cells. In most cases of cortical dysplasia, however, a microscope is not necessary to detect that there is an abnormality present. In most cases of cortical dysplasia, it is evident that the normal gyral pattern of the brain is disturbed, sometimes resulting abnormally broad gyri, and sometimes in too many very small gyri. Three cases are presented that illustrate cortical dysplasia may be present in brains that appear normal on gross examination. The patients died at 10 months, and 3 and 7 years of age. All three patients had seizures and showed severe developmental defects. The seven-year old was only able to say about five simple words at the peak of his development. By the time he died of a respiratory tract infection, he was unresponsive to loud noises. No apparent malformations of the gyral pattern were evident in these brains. When the patients' brains were examined at autopsy, abnormally thickened areas of cerebral cortex were present, and microscopic examination showed disorganization of the normally six-layered cortex and abnormal large neurons. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1991

15. Specific Relationship Between Prefrontal Neuronal N-Acetylaspartate and Activation of the Working Memory Cortical Network in Schizophrenia

Author

Bertolino, Alessandro, Esposito, Giuseppe, Callicott, Joseph H., Mattay, Venkata S., Van Horn, John D., Frank, Joseph A., Berman, Karen Faith, and Weinberger, Daniel R.

Subjects
Cerebral cortex -- Abnormalities, Schizophrenia -- Physiological aspects, Memory -- Research, Health, Psychology and mental health
Abstract

Objective: Abnormal activation of the dorsolateral prefrontal cortex and a related cortical network during working memory tasks has been demonstrated in patients with schizophrenia, but the responsible mechanism has not been identified. The present study was performed to determine whether neuronal pathology of the dorsolateral prefrontal cortex is linked to the activation of the working memory cortical network in patients with schizophrenia. Method: The brains of 13 patients with schizophrenia and 13 comparison subjects were studied with proton magnetic resonance spectroscopic ((super 1)H-MRS) imaging (to measure N-acetylaspartate as a marker of neuronal pathology) and with [(super 15)O]water positron emission tomography (PET) during performance of the Wisconsin Card Sorting Test (to measure activation of the working memory cortical network). An independent cohort of patients (N=7) was also studied in a post hoc experiment with (super 1)H-MRS imaging and with the same PET technique during performance of another working memory task (the 'N-back' task). Results: Measures of N-acetylaspartate in the dorsolateral prefrontal cortex strongly correlated with activation of the distributed working memory network, including the dorsolateral prefrontal, temporal, and inferior parietal cortices, during both working memory tasks in the two independent groups of patients with schizophrenia. In contrast, N-acetylaspartate in other cortical regions and in comparison subjects did not show these relationships. Conclusions: These findings directly implicate a population of dorsolateral prefrontal cortex neurons as selectively accounting for the activity of the distributed working memory cortical network in schizophrenia and complement other evidence that dorsolateral prefrontal cortex connectivity is fundamental to the pathophysiology of the disorder.

Published
2000

17. Altered corticospinal projections to lower limb motoneurons in subjects with cerebral palsy

Author

Brouwer, B. and Ashby, P.

Subjects
Cerebral cortex -- Abnormalities, Cerebral palsy -- Physiological aspects, Motor neurons -- Abnormalities, Health
Abstract

Patients with cerebral palsy suffer from the effects of abnormal brain development. The condition is not progressive, but the neurological changes which result in the severe paralysis are not well understood. It has been found that the normal relationship between agonist and antagonist muscles is abnormal in some patients with cerebral palsy, hinting that the muscles may be inappropriately connected to the nerve cells. This observation has led to the examination of the connections of brain cells in the motor cortex to motor neurons in the lower spinal cord controlling the leg muscles. The examination was accomplished using an increasingly popular technique, transcranial magnetic stimulation. With this technique, magnetic coils are used to induce electrical current in a small area of the brain. So, for example, if magnetic stimulation over a particular spot results in a finger movement, then that area of the cortex is connected to that particular finger. When this method was used to examined 14 subjects with cerebral palsy, significant differences were found compared with 22 normal control subjects. In normal subjects, magnetic stimulation in the appropriate spot affects spinal motor neurons controlling the tibialis anterior muscle. However, little or no effect on the soleus muscle can be achieved in this way in normal subjects. It was found that both the tibialis anterior and the soleus can be stimulated to respond with equal ease in the patients with cerebral palsy. This suggests that the neural connections between the cells of the motor portion of the cerebral cortex and the motor neurons of the spinal cord are abnormal in patients with cerebral palsy. (Consumer Summary produced by Reliance Medical Information, Inc.)

Published
1991

20. Cholinergic Activity in Autism: Abnormalities in the Cerebral Cortex and Basal Forebrain

Author

Perry, Elaine K., Lee, Mandy L.W., Martin-Ruiz, Carmen M., Court, Jennifer A., Volsen, Stephen G., Merrit, Jenny, Folly, Elizabeth, Iversen, Portia E., Bauman, Margaret L., Perry, Robert H., and Wenk, Gary L.

Subjects
Cholinergic mechanisms -- Research, Autism -- Physiological aspects, Cerebral cortex -- Abnormalities, Prosencephalon -- Abnormalities, Health, Psychology and mental health
Abstract

Objective: Measures of cholinergic transmitter activity were investigated in patients with autism because of reported neuropathological abnormalities in cholinergic nuclei in the basal forebrain. Method: Levels of cholinergic enzyme and receptor activity were measured in the frontal and parietal cerebral cortex of deceased autistic adults, similarly aged normal adults without mental retardation, and nonautistic mentally retarded adults. The immunoreactivity levels of brain-derived neurotrophic factor and nerve growth factor were measured in the basal forebrain. Results: There were no differences between the autistic and comparison groups in choline acetyltransferase or acetylcholinesterase activity in the cerebral cortex and basal forebrain or in muscarinic [M.sub.2] receptor or [Alpha]-bungarotoxin binding within the cortex. Cortical [M.sub.1] receptor binding was up to 30% lower than normal in the autistic subjects, and the difference reached significance in the parietal cortex. In both the parietal and frontal cortices, differences in nicotinic receptors assessed by [[sup.3]H]epibatidine binding were significant and extensive (65%-73% lower in the autistic group than in the normal subjects); there were no differences in nicotine binding in the basal forebrain. Immunochemical analysis indicated lower levels of both the [[Alpha].sub.4] and [[Beta].sub.2] nicotinic receptor subunits in the parietal cortex. The [M.sub.1] receptor abnormality was not evident in the nonautistic group with mental retardation, although the lower [[sup.3]H]epibatidine binding was apparent. In the basal forebrain, the level of brain-derived neurotrophic factor in the autistic group was three times as high as the level of the normal group. Conclusions: These neurochemical abnormalities implicate the cholinergic system in developmental disorders such as autism and suggest the potential for intervention based on cholinergic receptor modulation. (Am J Psychiatry 2001; 158:1058-1066)

Published
2001

21. Relation of Prefrontal Cortex Dysfunction to Working Memory and Symptoms in Schizophrenia

Author

Perlstein, William M., Carter, Cameron S., Noll, Douglas C., and Cohen, Jonathan D.

Subjects
Schizophrenia -- Physiological aspects, Cerebral cortex -- Abnormalities, Short-term memory -- Physiological aspects, Health, Psychology and mental health
Abstract

Objective: The dorsolateral prefrontal cortex has been implicated in both working memory and the pathophysiology of schizophrenia. A relationship among dorsolateral prefrontal cortex activity, working memory dysfunction, and symptoms in schizophrenia has not been firmly established, partly because of generalized cognitive impairments in patients and task complexity. Using tasks that parametrically manipulated working memory load, the authors tested three hypotheses: 1) patients with schizophrenia differ in prefrontal activity only when behavioral performance differentiates them from healthy comparison subjects, 2) dorsolateral prefrontal cortex dysfunction is associated with poorer task performance, and 3) dorsolateral prefrontal cortex dysfunction is associated with cognitive disorganization but not negative or positive symptoms. Method: Seventeen conventionally medicated patients with schizophrenia and 16 healthy comparison subjects underwent functional magnetic resonance imaging while performing multiple levels of the 'n-back' sequential-letter working memory task. Results: Patients with schizophrenia showed a deficit in physiological activation of the right dorsolateral prefrontal cortex (Brodmann's area 46/9) in the context of normal task-dependent activity in other regions, but only under the condition that distinguished them from comparison subjects on task performance. Patients with greater dorsolateral prefrontal cortex dysfunction performed more poorly. Dorsolateral prefrontal cortex dysfunction was selectively associated with disorganization symptoms. Conclusions: These results are consistent with the hypotheses that working memory dysfunction in patients with schizophrenia is caused by a disturbance of the dorsolateral prefrontal cortex and that this disturbance is selectively associated with cognitive disorganization. Further, the pattern of behavioral performance suggests that dorsolateral prefrontal cortex dysfunction does not reflect a deficit in the maintenance of stimulus representations per se but points to deficits in more associative components of working memory. (Am J Psychiatry 2001; 158:1105-1113)

Published
2001

22. Three-Dimensional Mapping of Gyral Shape and Cortical Surface Asymmetries in Schizophrenia: Gender Effects

Author

Narr, Katherine L., Thompson, Paul M., Sharma, Tonmoy, Moussai, Jacob, Zoumalan, Chris, Rayman, Janice, and Toga, Arthur W.

Subjects
Schizophrenia -- Physiological aspects, Brain -- Abnormalities, Cerebral cortex -- Abnormalities, Health, Psychology and mental health
Abstract

Objective: People with schizophrenia exhibit abnormalities in brain structure, often in the left hemisphere. Disturbed structural lateralization is controversial, however, and effects appear mediated by gender. The authors mapped differences between schizophrenic and normal subjects in gyral asymmetries, complexity, and variability across the entire cortex. Method: Asymmetry and shape profiles for 25 schizophrenic patients (15 men) and 28 demographically similar normal subjects (15 men) were obtained for 38 gyral regions, including the sylvian fissure and temporal and postcentral gyri, by using magnetic resonance data and a novel surface-based mesh-modeling approach. Cortical complexity was examined for sex and diagnosis effects in lobar regions. Intragroup variability was quantified and visualized to assess regional group abnormalities at the cortical surface. Results: The patients showed greater variability in frontal areas than the comparison subjects. They also had significant deviations in gyral complexity asymmetry in the superior frontal cortex. In temporoparietal regions, significant gyral asymmetries were present in both groups. Sex differences were apparent in superior temporal gyral measures, and cortical complexity in inferior frontal regions was significantly greater in men. Conclusions: Cortical variability and complexity show regional abnormalities in the frontal cortex potentially specific to schizophrenia. The results indicate highly significant temporoparietal gyral asymmetries in both diagnostic groups, contrary to reports of less lateralization in schizophrenia. Substantially larger study groups are necessary to isolate smaller deviations in surface asymmetries, if present in schizophrenia, suggesting their diagnostic value is minimal. (Am J Psychiatry 2001; 158:244-255)

Published
2001

23. Cognitive Outcome of Children with Epilepsy and Malformations of Cortical Development

Subjects
Cerebral cortex -- Abnormalities, Epilepsy in children -- Prognosis, Cognition in children -- Abnormalities, Health, Prognosis, Abnormalities
Abstract

Cognitive Outcome of Children with Epilepsy and Malformations of Cortical Development Klein B, Levin BE, Duchowny MS, Llabre MM. Neurology. 2000;55:230-235. Summary: To define the relationship between developmental malformations of [...]

Published
2001

24. Feeling Unreal: A PET Study of Depersonalization Disorder

Author

Simeon, Daphne, Guralnik, Orna, Hazlett, Erin A., Spiegel-Cohen, Jacqueline, Hollander, Eric, and Buchsbaum, Monte S.

Subjects
PET imaging -- Usage, Depersonalization -- Diagnosis, Glucose metabolism -- Physiological aspects, Cerebral cortex -- Abnormalities, Health, Psychology and mental health
Abstract

Objective: The goal of this study was to assess brain glucose metabolism and its relationship to dissociation measures and clinical symptoms in DSM-IV depersonalization disorder. Method: Positron emission tomography scans coregistered with magnetic resonance images of eight subjects with depersonalization disorder were compared to those of 24 healthy comparison subjects. The two groups did not differ in age, sex, education, performance on a baseline neuropsychological battery, or performance on a verbal learning task administered during [[sup.18]F] fluorodeoxyglucose uptake. A cortical analysis by individual Brodmann's areas was performed. Results: Compared to the healthy subjects, subjects with depersonalization disorder showed significantly lower metabolic activity in right Brodmann's areas 22 and 21 of the superior and middle temporal gyri and had significantly higher metabolism in parietal Brodmann's areas 7B and 39 and left occipital Brodmann's area 19. Dissociation and depersonalization scores among the subjects with depersonalization disorder were significantly positively correlated with metabolic activity in area 7B. Conclusions: Depersonalization appears to be associated with functional abnormalities along sequential hierarchical areas, secondary and cross-modal, of the sensory cortex (visual, auditory, and somatosensory), as well as areas responsible for an integrated body schema. These findings are in good agreement with the phenomenological conceptualization of depersonalization as a dissociation of perceptions as well as with the subjective symptoms of depersonalization disorder.

Published
2000

26. Primary microcephaly with ASPM mutation shows simplified cortical gyration with antero-posterior gradient pre- and post-natally.

Author

Désir, Julie, Cassart, Marie, David, Philippe, Van Bogaert, Patrick, Abramowicz, Marc, Désir, Julie, Cassart, Marie, David, Philippe, Van Bogaert, Patrick, and Abramowicz, Marc

Abstract

Primary microcephaly is a disorder of brain development characterized by a congenitally small but normally formed brain, and non-progressive mild-to-moderate mental retardation. Most cases are inherited in an autosomal recessive pattern, with genetic heterogeneity, the ASPM locus being most common. Postnatal imaging data are scarce and prenatal imaging unreported. Microcephaly with simplified gyral pattern shares features with primary microcephaly, but it is not clear whether these disorders are part of a phenotypic continuum. We examined a consanguineous family with a daughter affected with primary microcephaly and an ongoing pregnancy. We performed prenatal and postnatal brain magnetic resonance imaging and genetic analyses in the course of genetic evaluation. The affected daughter and the fetus were homozygous for polymorphic markers linked to the ASPM locus, and we identified a novel, truncating ASPM mutation by direct sequencing of the gene. Imaging at 30 and 35 gestational weeks showed microcephaly with simplified gyration, more severe anteriorly. The antero-posterior gradient of gyration persisted 1 week after birth. Brain imaging in the affected sister also showed some degree of a predominantly anterior simplification of gyration. Our data suggest that one form of autosomal recessive microcephaly is allelic to at least a subset of microcephaly with simplified gyral pattern, and that the neuronal depletion associated with the ASPM defect predominantly affects the anterior cortex., Case Reports, Journal Article, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published

Published
2008

27. Supratentorial functional disturbances in two children with cerebellar cortical dysplasia.

Author

Jissendi Tchofo, Patrice, De Tiege, Xavier, Goldman, Serge, Van Bogaert, Patrick, David, Philippe, Pruvo, J P, Soto Ares, G, Jissendi Tchofo, Patrice, De Tiege, Xavier, Goldman, Serge, Van Bogaert, Patrick, David, Philippe, Pruvo, J P, and Soto Ares, G

Abstract

When evaluating children with mental retardation, subtle cerebral and cerebellar morphologic anomalies are often noted at Magnetic Resonance Imaging (MRI). Some, such as cerebellar cortical dysplasia (CCD), have been considered as subtle markers of cerebral dysgenesis. Their functional significance and their effect on brain function, remain unknown. To study supratentorial functional disturbances related to CCD we performed Positron-Emission-Tomography (PET) studies in two children with isolated CCD, in order to investigate the degree of involvement of supratentorial structures. One had developmental delay, motor disturbances and ataxia, and the other one only had mental retardation. PET studies revealed hypoperfusion and hypometabolism within the vermis, thalamus and the right striatum in one case, and hypometabolism in the basal ganglia and cerebellar deep grey nuclei in the other case. Our results could lead to a hypothesis explaining motor disturbances as well as cognitive impairment, and could suggest a pathological functional significance of CCD. Nevertheless, the relationship between these findings and mental retardation needs further investigation., Case Reports, Journal Article, info:eu-repo/semantics/published

Published
2004

28. Cerebral dysplasias: reviewed from a neurophysiological perspective.

Author

Boyd, S G, Dan, Bernard, Boyd, S G, and Dan, Bernard

Abstract

Improvements in neuroimaging techniques have highlighted the role of cerebral dysplasia in developmental disorders and in epilepsy. The current classification is founded on the presumed timing of the first insult as deduced from the imaging appearances. Although clinical neurophysiological findings are often non-specific, several unusual patterns have been reported in association with certain types of malformation. These include the high amplitude rhythmic activities of lissencephaly, and focal rhythmic spikes. In this general review, we describe the electroence-phalographic and evoked potential findings in a wide range of cerebral dysplasias, including our personal experience of rare conditions such as Ramer-Lin syndrome. We focus on their role in assessment and on potential insights into pathophysiology., Journal Article, Research Support, Non-U.S. Gov't, Review, info:eu-repo/semantics/published

Published
2001

29. MRI spectrum of cortical malformations in tuberous sclerosis complex.

Author

Christophe, Catherine, Sekhara, Tayeb, Rypens, Françoise, Ziereisen, France, Christiaens, Florence, Dan, Bernard, Christophe, Catherine, Sekhara, Tayeb, Rypens, Françoise, Ziereisen, France, Christiaens, Florence, and Dan, Bernard

Abstract

The diagnostic and prognostic value of magnetic resonance imaging in the tuberous sclerosis complex has increasingly been recognized. In this paper, we review the presumed pathogenesis of the cerebral dysgenesis seen in this condition in the light of magnetic resonance imaging features of selected patients. In addition to typical findings related to tubers, we show and discuss varied cortical malformations (from simple localized cortical dysplasia to transmantle dysplasia and schizencephaly) similar to those seen in sporadic cerebral dysgenesis. These cases support the hypothesis that the tuberous sclerosis complex focally affects the radial glial-neuronal complex as a basic unit for brain development. Abnormal stem cells would create dysplastic glia and neurons that fail to differentiate, proliferate, migrate and form a normally organized cortex., Case Reports, Journal Article, info:eu-repo/semantics/published

Published
2000

30. Time course of effects of unilateral lesions of the nucleus basalis of Meynert on glucose utilization by the cerebral cortex. Positron tomography in baboons

Author

Kiyosawa, Motohiro, Baron, Jean-Claude, Hamel, Edith, Pappata, Sabina, Duverger, Danielle, Riche, Danielle, Mazoyer, Bernard, Naquet, Robert, MacKenzie, E., and MacKenzie, Eric T.

Subjects
Alzheimer's disease -- Causes of, Brain -- Abnormalities, Cerebral cortex -- Abnormalities, Glucose metabolism -- Abnormalities, Health
Abstract

There is a relationship between the rate at which the 'grey matter' of the brain, the front main folded surface part (the cortex), consumes sugar (glucose) and damage to a certain part of the brain beneath this part (the nucleus basalis of Meynert). A few days after damage on one side of the brain to the nucleus basalis, both sides of the grey matter of the brain consume significantly less sugar, but sugar consumption returns to normal over a few months. In certain parts (frontal, temporal, and parietal lobes) of the brain on the side that is damaged, there is a decrease in production of a substance (choline acetyltransferase) which facilitates transmission of nerve impulses. The less the brain is damaged, the smaller the drop in production of this substance and in consumption of sugar. The reason both sides of the brain consume less sugar while only one side produces less of the acetyltransferase enzyme is probably because damage to one side reduces the number of tasks the brain as a whole attempts to perform. The nerves of the brain eventually adjust to their damaged condition and start to work normally again. This may all be relevant to similar brain malfunctions that occur in Alzheimer's disease.

Published
1989

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