Coherence on Electroencephalography and Aberrant Functional Organisation of the Brain in Schizophrenic Patients During Activation Tasks

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.

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.


1980 ◽  
Vol 50 (2) ◽  
pp. 371-375
Author(s):  
Milton Turbiner ◽  
Robert M. Derman

This study was designed to assess the discriminative capacity of a visual-searching task for brain damage, as described by Goldstein and Kyc (1978) , for 10 hospitalized male, brain-damaged patients, 10 hospitalized male schizophrenic patients, and 10 normal subjects in a control group, all of whom were approximately 65 yr. old. The derived data indicated, at a statistically significant level, that the visual-searching task was effective in successfully classifying 80% of the brain-damaged sample when compared to the schizophrenic patients and discriminating 90% of the brain-damaged patients from normal subjects.


1947 ◽  
Vol 93 (391) ◽  
pp. 318-332 ◽  
Author(s):  
H. H. Fleischhacker

Commenting on the different symptoms produced by disturbances of the left hemisphere (aphasia, apraxia, etc.) and of the right (dreamy states, hallucinations, etc.), Hughlings Jackson on many occasions pointed out that there exists a “duality” of the brain; the anterior parts of the left hemisphere serving more controlled and objective purposes, the posterior parts of the right more subjective† and the anterior parts of the right serving more automatic purposes. Consequently, quoting Bastian and Rosenthal to support him, he tendered the suggestion that “mental” symptoms might be indicative of a disturbance particularly of the posterior parts of the right hemisphere (in right-handed people).


1977 ◽  
Vol 45 (3) ◽  
pp. 723-728 ◽  
Author(s):  
Paul L. Wang

49 brain-damaged patients (15 with left-hemisphere lesions, 19 with right-hemisphere lesions, and 15 with bilateral lesions) and 17 non-brain-damaged patients were administered the Hooper Visual Organization Test. Non-brain-damaged patients performed significantly better than the brain-damaged patients; however, the differences among the brain-damaged patients were not significant. Hooper Visual Organization Test seems valuable for identifying organicity but its usefulness for determining lateralization is limited. It is also suggested that both hemispheres form a close functional loop in subserving visual organization ability. A hypothetical diagram has been proposed to describe the functional dynamics of the visual synthesis ability measured by the Visual Organization Test.


1989 ◽  
Vol 1 (2) ◽  
pp. 187-193 ◽  
Author(s):  
Michael S. Gazzaniga ◽  
George A. Miller

A commissurotomy patient with limited language in the right hemisphere was tested for ability to recognize direct and indirect antonyms. Normal subjects performing this task recognize direct antonyms faster than indirect. The patient's left hemisphere responded normally, but his right showed no difference in response to direct and indirect antonyms. It is concluded that the patient's right hemisphere had not learned that particular pairs of adjectives (the direct antonyms) can be used to represent the attribute whose contrasting values they express. Such learning normally occurs in the course of reasoning about attributes of things and events, but presumably failed to occur in this patient's right hemisphere because its powers of reasoning are severely limited.


2021 ◽  
Vol 4 ◽  
Author(s):  
Sergio Ledesma ◽  
Mario-Alberto Ibarra-Manzano ◽  
Dora-Luz Almanza-Ojeda ◽  
Pascal Fallavollita ◽  
Jason Steffener

In this study, Artificial Intelligence was used to analyze a dataset containing the cortical thickness from 1,100 healthy individuals. This dataset had the cortical thickness from 31 regions in the left hemisphere of the brain as well as from 31 regions in the right hemisphere. Then, 62 artificial neural networks were trained and validated to estimate the number of neurons in the hidden layer. These neural networks were used to create a model for the cortical thickness through age for each region in the brain. Using the artificial neural networks and kernels with seven points, numerical differentiation was used to compute the derivative of the cortical thickness with respect to age. The derivative was computed to estimate the cortical thickness speed. Finally, color bands were created for each region in the brain to identify a positive derivative, that is, a part of life with an increase in cortical thickness. Likewise, the color bands were used to identify a negative derivative, that is, a lifetime period with a cortical thickness reduction. Regions of the brain with similar derivatives were organized and displayed in clusters. Computer simulations showed that some regions exhibit abrupt changes in cortical thickness at specific periods of life. The simulations also illustrated that some regions in the left hemisphere do not follow the pattern of the same region in the right hemisphere. Finally, it was concluded that each region in the brain must be dynamically modeled. One advantage of using artificial neural networks is that they can learn and model non-linear and complex relationships. Also, artificial neural networks are immune to noise in the samples and can handle unseen data. That is, the models based on artificial neural networks can predict the behavior of samples that were not used for training. Furthermore, several studies have shown that artificial neural networks are capable of deriving information from imprecise data. Because of these advantages, the results obtained in this study by the artificial neural networks provide valuable information to analyze and model the cortical thickness.


Psychiatry ◽  
2020 ◽  
Vol 18 (3) ◽  
pp. 14-21
Author(s):  
E. V. Iznak ◽  
E. V. Damyanovich ◽  
N. S. Levchenko ◽  
I. V. Oleichik ◽  
A. F. Iznak

Background: non-suicidal self-injury (NSSI) in adolescence is a significant risk factor for suicide, and therefore, the search for neurobiological markers and predictors of risk for suicidal intentions and actions seems to be an urgent task. In particular, quantitative EEG parameters can be such predictors.Objective: to identify the features of EEG in female adolescents with endogenous depressive conditions, manifested only by NSSI without suicidal intentions, in comparison with the EEG of patients who had suicidal auto-aggressive behavior (SAB) in the structure of depression.Patients and methods: the study was conducted as a comparative clinical and neurophysiological. The study included 45 female patients aged 16–25 years with endogenous depressive conditions, divided into 2 subgroups: those who showed only NSSI (NSSI subgroup, 21 patients), or who had a history of SAB (SAB subgroup, 24 patients). Clinical-psychopathological, psychometric, neurophysiological and statistical methods were used.Results and its discussion: intergroup differences were revealed in relation to the ratio and hemispheric asymmetry of the EEG spectral power of narrow frequency sub-bands of the parietal-occipital alpha rhythm. In the SAB subgroup alpha-2 (9–11 Hz) rhythm spectral power is higher than in the NSSI subgroup, the focus of alpha-2 spectral power is located in the right hemisphere, and alpha-3 sub-band (11–13 Hz) spectral power is higher than of alpha-1 (8–9 Hz). In the NSSI subgroup, alpha-1 (8–9 Hz) sub-band spectral power are higher than of alpha-3 (11–13 Hz), and focuses of alpha-2 (9–11 Hz) and alpha-3 (11–13 Hz) rhythms are localized in the left hemisphere. The results are discussed in terms of functional specialization of the brain hemispheres in relation to the regulation of emotions and control of behavior.Conclusions: the spatial distribution of the EEG frequency components in the SAB subgroup reflects the greater activation of the brain left hemisphere that is more typical for the EEG of individuals with an increased risk of suicide. In the NSSI subgroup, the right hemisphere is relatively more activated that is more typical for EEG in depressive disorders.The results obtained allow the use of quantitative EEG data to clarify the degree of suicidal risk in depressed female adolescents with non-suicidal self-injury.


2021 ◽  
Author(s):  
Yuichiro Tsuji ◽  
Naosuke Nonoguchi ◽  
Daisuke Okuzaki ◽  
Yusuke Wada ◽  
Daisuke Motooka ◽  
...  

Abstract Background: This study investigated whether the effect of changes in the microenvironment of parenchymal brain tissue caused by radiotherapy for malignant brain tumors affect the recurrence and progression of glioma. Methods: 3 months after the same 65-Gy irradiation had been applied to the right hemisphere. Irradiated Fisher rats were divided into three groups for in vitro assay as follows. IR/Ipsi-brain; the right-hemisphere tissue was used for experiments. IR/Contra-brain; the left-hemisphere tissue was used. Sham-IR/Brain; sham-irradiation was applied to the brain, and the right-hemisphere tissue was used. The effects of proteins extracted from the brains directly or indirectly affected by irradiation on the growth of F98 cells, the effect on tube formation, the influence on tumor biology, and the influence on cytokine production were investigated. Additionally, irradiated animals were divided into three groups for in vivo assay as follows. IR/Ipis-tumor; F98 cells (a glioma cell line) were transplanted to the right hemisphere. IR/Contra-tumor; F98 cells were transplanted to the left hemisphere. Sham-IR/Tumor; F98 cells were transplanted to the right hemisphere without irradiation. The median survival time of F98 transplanted rats was also examined. Results: X-ray irradiation promoted the secretion of cytokines such as TNFα, TGF-β1, VEGF-A, and CXCL12 from the irradiated brain. F98 glioma cells implanted in the irradiated brains showed significantly high proliferation and angiogenesis ability, and the post-irradiation F98 tumor-implanted rats showed a shorter median survival time compared to the Sham-irradiation group.Conclusions: These results indicate that the up-regulation of CXCL12-CXCR4 axis by radiotherapy could promote tumor proliferation. Radiation therapy is a standard treatment for malignant gliomas including glioblastoma multiforme, but the current study suggests that the microenvironment around the brain tissue in the chronic phase after exposure to X-ray radiation becomes suitable for glioma cell growth and invasion.


2021 ◽  
pp. 170-174
Author(s):  
Amy M. Belfi ◽  
Agathe Pralus ◽  
Catherine Hirel ◽  
Daniel Tranel ◽  
Barbara Tillmann ◽  
...  

The study under discussion sought to investigate the hemispheric laterality of musical emotions: Is one hemisphere of the brain preferentially involved in recognizing emotions in music? The authors took a neuropsychological approach to answer this question by studying emotional judgments of music in people with brain damage to either hemisphere. Their results indicated that individuals with left hemisphere damage were significantly impaired in recognizing musical emotions as compared to healthy comparison participants. In contrast, individuals with right hemisphere damage were not impaired at identifying emotions in music, but rated the perceived intensity of the emotions lower for sadness and fear (as compared to joy and serenity). Their work suggests that the identification of emotions in music and the perceived intensity of the emotions expressed may rely on different hemispheres of the brain.


2012 ◽  
Vol 10 (1) ◽  
pp. 51-53
Author(s):  
Vladimir Vladimirovich Mihkeev ◽  
Vera Vasilievna Marysheva ◽  
Boris Nikolaevich Bogomolov ◽  
Lubov Vladislavovna Zhukova-Williams

The effect of aminothiol antihipoxants amthizol and its analogue VM-606 on the resistance of the SHR mice males to an acute hypoxia with hypercapnia under conditions of isolated functioning of one of the hemispheres of the brain was studied. Antihypoxic agent amthizol 25 mg/kg increases life time of naïve mice by 46.2%. The drug acted on the sham-operated mice more slightly, increasing of their life only on 28.1% (p<0.01). Administration of amthizol under conditions of functioning of the right hemisphere significantly enhanced (+64.8%) the life time of mice. No antihypoxic effect was registered after administration of amthizol to mice with active left hemisphere: the result was the same as in mice without amthizol. Therefore, antihypoxic effect of amthizol was due to its action on the right (but not the left) hemisphere of the brain. VM-606 possessed more antihypoxic activity in comparison with amthizol. After unilateral cortical inactivation, VM-606 increased life time of mice both in active right and active left hemispheres, but in more degree in active right hemisphere. Thus, interhemispheric differences in resistance of mice to hypoxia with hypercapnia were diminished. Therefore, the differences between amthizol and VM-606 are the followings: amthizol inverts interhemispheric relations in hypoxia whereas VM-606 diminishes them.


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