scholarly journals Brain Organization in Schizophrenia

1986 ◽  
Vol 6 (4) ◽  
pp. 441-446 ◽  
Author(s):  
Nora D. Volkow ◽  
Jonathan D. Brodie ◽  
Alfred P. Wolf ◽  
Francisco Gomez-Mont ◽  
Robert Cancro ◽  
...  

Brain metabolism was measured with positron emission tomography and [11C]deoxyglucose during baseline and during a visual task in 12 normal subjects and 18 schizophrenic patients. Global measures of metabolism for 11 brain regions were transformed into relative values by dividing them by the metabolic value for whole brain. Factor analysis was accomplished on the matrix of intercorrelations among the relative regional values for the normal and for the schizophrenic patients under baseline and under the task. Four factors that revealed independently varying metabolism in frontal, occipital, left-versus-right hemisphere, and subcortical structures were obtained. The frontal and subcortical factors discriminated between normal subjects and schizophrenic patients, whereas the occipital factor discriminated between baseline and task. Although activity in these individual regions varied significantly, it was the pattern of differences in regional metabolic activity that best discriminated between diagnostic groups and testing conditions.

1996 ◽  
Vol 26 (3) ◽  
pp. 605-612 ◽  
Author(s):  
S. L. Morrison-Stewart ◽  
D. Velikonja ◽  
W. C. Corning ◽  
P. Williamson

SynopsisThirty schizophrenic patients (20 medicated, 10 off medication) were compared with 30 normal controls subjects matched for age, sex, handedness and intelligence. During the performance of a frontal activation task, normal subjects showed increased interhemispheric coherence between anterior brain regions. Schizophrenic patients did not show the same amount of bilateral anterior activation. During the performance of right hemisphere cognitive activation tasks, normal subjects and medicated schizophrenic patients showed significantly reduced bilateral interhemispheric coherence patterns, while the drug-free schizophrenic patients showed a trend towards this same pattern. It is suggested that these findings provide additional evidence for an aberrant functional organization of the brain in schizophrenia.


2013 ◽  
Vol 109 (5) ◽  
pp. 1444-1456 ◽  
Author(s):  
B. J. Shannon ◽  
R. A. Dosenbach ◽  
Y. Su ◽  
A. G. Vlassenko ◽  
L. J. Larson-Prior ◽  
...  

It has been posited that a critical function of sleep is synaptic renormalization following a net increase in synaptic strength during wake. We hypothesized that wake would alter the resting-state functional organization of the brain and increase its metabolic cost. To test these hypotheses, two experiments were performed. In one, we obtained morning and evening resting-state functional MRI scans to assess changes in functional brain organization. In the second experiment, we obtained quantitative positron emission tomography measures of glucose and oxygen consumption to assess the cost of wake. We found selective changes in brain organization. Most prominently, bilateral medial temporal regions were locally connected in the morning but in the evening exhibited strong correlations with frontal and parietal brain regions involved in memory retrieval. We speculate that these changes may reflect aspects of memory consolidation recurring on a daily basis. Surprisingly, these changes in brain organization occurred without increases in brain metabolism.


1988 ◽  
Vol 8 (4) ◽  
pp. 502-512 ◽  
Author(s):  
Elsa J. Bartlett ◽  
Jonathan D. Brodie ◽  
Alfred P. Wolf ◽  
David R. Christman ◽  
Eugene Laska ◽  
...  

Positron emission tomography with 11C-2-deoxyglucose was used to determine the test-retest variability of regional cerebral glucose metabolism in 22 young normal right-handed men scanned twice in a 24-h period under baseline (resting) conditions. To assess the effects of scan order and time of day on variability, 12 subjects were scanned in the morning and afternoon of the same day (a.m.-p.m.) and 10 in the reverse order (p.m.-a.m.) with a night in between. The effect of anxiety on metabolism was also assessed. Seventy-three percent of the total subject group showed changes in whole brain metabolism from the first to the second measurement of 10% or less, with comparable changes in various cortical and subcortical regions. When a scaling factor was used to equate the whole brain metabolism in the two scans for each individual, the resulting average regional changes for each group were no mote than 1%. This suggests that the proportion of the whole brain metabolism utilized regionally is stable in a group of subjects over time. Both groups of subjects had lower morning than afternoon metabolism, but the differences were slight in the p.m.-a.m. group. One measure of anxiety (pulse at fun 1) was correlated with run 1 metabolism and with the percentage of change from run 1 to run 2. No significant run 2 correlations were observed. This is the first study to measure test-retest variability in cerebral glucose metabolism in a large sample of young normal subjects. It demonstrates that the deoxyglucose method yields low Intrasubject variability and high stability over a 24-h period.


1991 ◽  
Vol 159 (5) ◽  
pp. 636-644 ◽  
Author(s):  
Sandra L. Morrison-Stewart ◽  
Peter C. Williamson ◽  
William C. Corning ◽  
Stanley P. Kutcher ◽  
Harold Merskey

Thirty schizophrenic patients (20 medicated, 10 off medication) were compared with 30 normal control subjects matched for age, sex, handedness, and intelligence. During the performance of left-hemisphere cognitive activation tasks, normal subjects had significantly increased EEG alpha coherence in areas related to left focal frontal sites, with decreases in temporal and posterior areas. Schizophrenic patients did not show the same degree of focal activation of left frontal areas. During the performance of right-hemisphere cognitive activation tasks, normal subjects and schizophrenic patients had similar patterns of right posterior increases in alpha coherence. Discriminant analyses were able to classify 81.4% of all subjects correctly. It is suggested that the findings indicate an aberrant functional organisation of the brain in schizophrenia, particularly affecting the left hemisphere.


2017 ◽  
Vol 29 (1) ◽  
pp. 122
Author(s):  
H. J. Oh ◽  
J. Moon ◽  
G. A. Kim ◽  
S. Lee ◽  
S. H. Paek ◽  
...  

Due to similarities between human and porcine, pigs have been proposed as an excellent experimental animal for human medical research. Especially in paediatric brain research, piglets share similarities with human infants in the extent of peak brain growth at the time of birth and the growth pattern of brain. Thus, these findings have supported the wider use of pigs rather than rodents in neuroscience research. Previously, we reported the production of porcine model of Parkinson's disease (PD) by nuclear transfer using donor cell that had been stably infected with lentivirus containing the human α-synuclein gene. The purpose of this study was to determine the alternation of brain metabolism and dopaminergic neuron destruction using noninvasive method in a 2-yr-old PD model and a control pig. The positron emission tomography (PET) scan was done using Biograph TruePoint40 with a TrueV (Siemens, Munich, Germany). The [18F]N-(3-fluoropropyl)-2β-carbomethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) was administrated via the ear vein. Static images of the brain for 15 min were acquired from 2 h after injection. The 18F-fluorodeoxy-D-glucose PET (18F-FDG PET) images of the brain were obtained for 15 min at 45 min post-injection. Computed tomography (CT) scan and magnetic resonance imaging (MRI) were performed at the same location of the brain. In both MRI and CT images, there was no difference in brain regions between PD model and control pigs. However, administration of [18F]FP-CIT was markedly decreased in the bilateral putamen of the PD model pig compared with the control pigs. Moreover, [18F]FP-CIT administration was asymmetrical in the PD model pig but it was symmetrical in control pigs. Regional brain metabolism was also assessed and there was no significant difference in cortical metabolism of PD model and control pigs. We demonstrated that PET imaging could provide a foundation for translational Parkinson neuroimaging in transgenic pigs. In the present study, a 2-yr-old PD model pig showed dopaminergic neuron destruction in brain regions. Therefore, PD model pig expressing human α-synuclein gene would be an efficient model for human PD patients. This study was supported by Korea IPET (#311011–05–5-SB010), Research Institute for Veterinary Science, TS Corporation and the BK21 plus program.


1989 ◽  
Vol 9 (3) ◽  
pp. 388-397 ◽  
Author(s):  
A. V. Levy ◽  
J. D. Brodie ◽  
JJ. A. G. Russell ◽  
N. D. Volkow ◽  
E. Laska ◽  
...  

The method of centroids is an approach to the analysis of three-dimensional whole-brain positron emission tomography (PET) metabolic images. It utilizes the brain's geometric centroid and metabolic centroid so as to objectively characterize the central tendency of the distribution of metabolic activity in the brain. The method characterizes the three-dimensional PET metabolic image in terms of four parameters: the coordinates of the metabolic centroid and the mean metabolic rate of the whole brain. These parameters are not sensitive to spatially uniform random noise or to the position of the subject's head within a uniform PET camera field of view. The method has been applied to 40 normal subjects, 22 schizophrenics who were treated with neuroleptics, and 20 schizophrenics who were neuroleptic-free. The mean metabolic centroid of the normal subjects was found to be superior to the mean geometric centroid of the brain. The mean metabolic centroid of chronic schizophrenics is lower and more posterior to the mean geometric centroid than is that of normals. This difference is greater in medicated than in unmedicated schizophrenics. The posterior and downward displacement of the mean metabolic centroid is consistent with the concepts of hypofrontality, hyperactivity of subcortical structures, and neuroleptic effect in schizophrenics.


1995 ◽  
Vol 80 (3_suppl) ◽  
pp. 1275-1282 ◽  
Author(s):  
G. Kaprinis ◽  
J. Nimatoudis ◽  
A. Karavatos ◽  
D. Kandylis ◽  
S. Kaprinis

To study the functional organization of the cerebral hemispheres in patients with bipolar psychosis using a verbal dichotic listening test for pairs of digits 26 patients were tested twice, during the acute expression of manic phase and after recovery. The patient group during the manic phase did not support the expected right-ear advantage of normal subjects on verbal dichotic tests but showed a statistically significant left-ear advantage, which shifted after recovery toward the typical normal asymmetry. Comparing patients during the manic phase and after recovery showed that the left-ear advantage as well as the shift in right-ear advantage after recovery was due to the reduction of left-ear performance. From the over-all neuropsychological findings for these patients mania may be hypothesized to be characterized by overactivation of the right hemisphere. This phaenomenon seems associated with acuteness of the symptoms of the psychotic disorder.


1990 ◽  
Vol 157 (4) ◽  
pp. 562-570 ◽  
Author(s):  
J. M. Cleghorn ◽  
E. S. Garnett ◽  
C. Nahmias ◽  
G. M. Brown ◽  
R. D. Kaplan ◽  
...  

Regions of the brain involved in language and attention were studied using [18F]-fluorodeoxyglucose in PET. In nine chronic DSM–III schizophrenic patients who had persistent auditory hallucinations, ten who had recovered from hallucinations and ten normal controls. In none of the regions examined was metabolic activity significantly different in hallucinating patients compared with that in other groups. However, a pattern of seven significant correlations of metabolic activity between language regions and between frontal and parietal cortex characterised the hallucinating but not the other groups. Three of the seven correlations were significantly greater in hallucinating patients than in the two other groups, and six were greater in hallucinating patients than controls. Metabolism in Broca's region and its right-hemisphere homologue correlated positively and significantly in the hallucinating group, as it did in anterior cingulate and left superior temporal areas, and in right frontal and parietal areas. Hallucination ratings correlated with metabolism in the anterior cingulate region.


2021 ◽  
Vol 4 (4) ◽  
pp. 01-07
Author(s):  
Francesco Crespi

Nicotine, a natural alkaloid derived from tobacco, is involved in various outcomes ranging from addiction to toxicity and/or neuro-protective actions. Nevertheless, the literature on the effects of nicotine administration upon the activity of brain regions is mixed; either increased, decreased, or no overall effect was reported when being evaluated by various methodologies such as positron emission tomography (PET), functional Magnetic Resonance Imaging (fMRI). In this work, Near Infrared Spectroscopy (NIRS) is applied as it allows monitoring oxygen saturation in the living tissue as well as changes in oxygenation of hemoglobin and when applied on brain studies, it gives indications of cerebral haemo-dynamics as well as brain metabolism. In particular, here NIRS has been applied in human volunteers as this methodology is based upon the use of harmless radiations so that to provide a non-invasive, non-ionizing procedure to monitor 2 main forms of hae­moglobin: oxy-haemoglobin (HbO2) and deoxy-haemoglobin (Hb). The data gathered indicate an overall positive influence of nicotine upon HbO2 levels, as well as total blood volume (V) therefore suggesting an increased brain metabolism. Finally these data further propose NIRS with its characteristics of noninvasiveness, easy to-use, portable, restraint-free therefore relatively psychologically undemanding, as replicable and ideal methodology for clinical applications and translational approaches.


CNS Spectrums ◽  
1997 ◽  
Vol 2 (10) ◽  
pp. 45-55 ◽  
Author(s):  
Mark S. George ◽  
Terence A. Ketter ◽  
Priti I. Parekh ◽  
Debra S. Gill ◽  
Lauren Marangell ◽  
...  

AbstractDepressed subjects have deficits in facialemotion recognition that resemble the deficits found in persons with focal right hemisphere brain damage. To locate the brain regions responsible for this problem, the authors imaged regional cerebral blood flow (rCBF) with H2O15 positron emission tomography in 10 mood-disordered patients, as well as in 10 age- and sex-matched healthy comparison subjects, while the subjects matched photographs for facial emotion or, as a control, facial identity. While matching faces for emotion, mood-disordered subjects had decreased rCBF activation bilaterally in their temporal lobes, as well as in the right insula, compared with healthy comparison subjects. Abnormal function of limbic and paraiimbic regions may partially explain the facial emotion-recognition deficits previously noted in depressed subjects.


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