Visual Organization Ability in Brain-Damaged Adults

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.

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.


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).


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.


1983 ◽  
Vol 11 (1) ◽  
pp. 65-76 ◽  
Author(s):  
John Meissner ◽  
Michael Pirot

Twenty males with a strong right hand preference underwent 120 simple reaction time trials to a 500 hz auditory stimulus presented to right, left and both ears. Ten Transcendental Meditators served as their own controls in twenty minute meditation and relaxation conditions and were also compared to a ten Non-Meditator control group who relaxed only in two 20-minute conditions. The reaction time trials were administered after the conditions. When the ears were compared to each other a significant right-ear (left hemisphere) advantage (REA) occurred in all relaxation conditions of the Meditator and Non-Meditator control groups. However, no REA emerged after meditation conditions of the Meditator group. The Meditator group after meditation compared to their own baseline relaxation condition showed a significant suppression of reaction time latencies to stimulation delivered to the left hemisphere and a significant facilitation to stimulation delivered to the right hemisphere. The meaning of these findings suggest Transcendental Meditation is an attentional strategy that disrupts the usual biases of the brain which also has implications as a clinical method. A neuropsychological explanation of the results suggest a comprehensive theory of Transcendental Meditation.


2008 ◽  
Vol 2 (4) ◽  
pp. 339-348 ◽  
Author(s):  
Renata Mancopes ◽  
Fernanda Schultz

Abstract Great emphasis has been placed on the right hemisphere, due to its possible selective contribution, in the processing of metaphorical statements. Objectives: To describe the processing of metaphors in the case of a patient with transcortical motor aphasia, using specific tests for patients with encephalic injuries of the right hemisphere, and to contribute to the discussion on the inter-hemispheric relationships associated with this function. Methods: A 54 year-old man with transcortical motor aphasia was evaluated three years after a left hemisphere stroke. The tasks of comprehension of metaphors were based on the subtest Metaphor Comprehension Task of the Montreal Evaluation of Communications Scale (MEC). Two metaphor comprehension tests were applied, in 45-minute sessions with a 48 hour interval between each. Test 1 involved comprehension of the metaphors according to the options offered, and Test 2 the comprehension of metaphors measured by response time and visual field. Results: Although the right hemisphere was not affected by the stroke in this case, difficulties were observed in the processing of metaphors. Conclusions: This study suggests that the left hemisphere participates in the processing of figurative meanings. The adaptability of the brain can also re-accommodate the uninjured areas of the brain, causing the dynamic of the brain to be modified. As a result, deducing cerebral functions based on clinical data can be problematic. The value of this study is that it can contribute to clinical aspects of language rehabilitation.


1988 ◽  
Vol 67 (3) ◽  
pp. 783-788 ◽  
Author(s):  
Bert De Brabander

The results of the experiment offer indirect evidence for the basic hypothesis that the brain self-regulates its own arousal and activation as a function of the intensity and type of ongoing cortical activity. When subjects perform a task which can be assumed to be primarily attended to by the right hemisphere, the result of a supplementary information-processing load seems to be increased arousal. On a task primarily attended to by the left hemisphere, the consequence is increased activation. The evidence is indirect because no measurements have been made of the neurological events and processes which are assumed to intervene in this self-regulation process. Although indirect, the evidence may help to formulate more precise psychological hypotheses about the factors controlling the putative effort system which, according to Pribram and McGuinness in 1975, coordinates the arousal and activation of cerebral processes.


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