Language and Reading in the Right Hemisphere: Highways or Byways of the Brain?

1990 ◽  
Vol 2 (3) ◽  
pp. 159-179 ◽  
Author(s):  
Kathleen Baynes
Keyword(s):  
Individual Variation ◽  
Right Hemisphere ◽  
Reading Processes ◽  
The Third ◽  
Normal Reading ◽  
Reading Errors ◽  
Limited Support ◽  
The Right ◽  
Disconfirming Evidence ◽  
The Brain

The literature pertaining to the representation of language in the right hemisphere of hemispherectomy and callosotomy patients is reviewed to ascertain whether it provides an empirical basis for the assertions that (1) the right hemisphere participates in the recovery of language in aphasia, (2) the right hemisphere mediates the reading errors of deep dyslexic and pure alexic patients, and (3) the right hemisphere plays a fixed role in normal reading processes. At present, there appears to be some support for the first assertion, limited support for the second (if individual variation in representation can be accepted), and disconfirming evidence for the third in the data from these populations.

Neurospect Findings in Patients Exposed to Neurotoxic Chemicals

1994 ◽  
Vol 10 (4-5) ◽  
pp. 561-571
Author(s):  
Gunnar Heuser ◽  
Ismael Mena ◽  
Francisca Alamos
Keyword(s):  
Elderly Patients ◽  
Qualitative Analysis ◽  
Right Hemisphere ◽  
Young Patients ◽  
Chronic Fatigue ◽  
Psychiatric Symptomatology ◽  
Elderly Individuals ◽  
Parietal Lobes ◽  
The Right ◽  
The Brain

Exposures to neurotoxic chemicals such as pesticides, glues, solvents, etc. are known to induce neurologic and psychiatric symptomatology. We report on 41 patients 16 young patients (6 males, 10 females, age 34 8 yrs.) and 25 elderly patients (9 males, 16 females, age 55 7 yrs). Fifteen of them were exposed to pesticides, and 29 to solvents. They were studied with quantitative and qualitative analysis of regional cerebral bood flow (rCBF), performed with 30 mCi of Xe-133 by inhalation, followed by 30 mCi of Tc-HMPAO given intravenously. Imaging was performed with a brain dedicated system, distribution of rCBF was assessed with automatic ROI definition, and HMPAO was normalized to maximal pixel activity in the brain. Results of Xe rCBF are expressed as mean and S.D. in ml/min/100g, and HMPAO as mean and S.D. uptake per ROI, and compared with age-matched controls 10 young and 20 elderly individuals. Neurotoxics HMPAO Uptake Young Elderly R. Orbital frontal R. Dorsal frontal .70 .66 p < 0.05 R. Temporal .64 p < 0.001 R. Parietal .66 .66 We conclude that patients exposed to chemicals present with diminished CBF, worse in the right hemisphere, with random presentation of areas of hypoperfusion, more prevalent in the dorsal frontal and parietal lobes. These findings are significantly different from observations in patients with chronic fatigue and depression, suggesting primary cortical effect, possibly due to a vasculitis process.

scholarly journals Morphology of the vertebral artery in Asian population

2014 ◽  
Vol 5 (4) ◽  
pp. 84-88 ◽  
Author(s):  
Maryna Alfaouri-Kornieieva ◽  
Azmy M Al-Hadidi
Keyword(s):  
Vertebral Artery ◽  
Asian Population ◽  
Outer Diameter ◽  
Medical Sciences ◽  
The Third ◽  
Asian Patients ◽  
Distal Loop ◽  
The Right ◽  
Occipital Lobes ◽  
The Brain

Background: Recent clinical trials have shown a rising trend of stroke in Asian population. Approximately 20% strokes of total occur at the vertebrobasilar basin that supplies the occipital lobes of the brain, the cerebellum, and the brainstem. The anatomical features and variability of the third segment of the vertebral artery (VA) in Asians are analyzed in this study. Methods: A prospective cohort study of 68 consecutive Asian patients underwent MRA examination for head and neck in the Department of Radiology of Hospital of University of Jordan from 1.10.2011 to 30.04.2012. The 116 VA were analyzed on the obtained angiograms. Results: The third segment (V3) of the VA was studied according to its conventional division into vertical, horizontal, and oblique parts. The mean outer diameter of the V3 varied up 3.18 ± 0.73 to 4.28 ± 1.08 mm. The parameter prevailed on the left in 91% cases and was greater in males, than in females. The distal loop of the VA projected downward in 26 cases on the right (78%) and in 28 cases on the left (74%). The tortuosity of loop?formations of V3 was evaluated subject to angles between their ascending and descending bends. Conclusion: In comparison with other ethnic groups, the V3 of the VA in Asians has lesser outer diameter, especially along its oblique part; the zero?distance between the occipital bone and horizontal segment of VA occurs more often (up to 26%); the Lang’s III type of V3 variability is the most common in Asians. DOI: http://dx.doi.org/10.3126/ajms.v5i4.6150 Asian Journal of Medical Sciences 2014 Vol.5(4); 84-88

scholarly journals Low-frequency electroencephalogram oscillations govern left-eye lateralization during anti-predatory responses in the music frog

2020 ◽  
Vol 223 (21) ◽  
pp. jeb232637
Author(s):  
Jiangyan Shen ◽  
Ke Fang ◽  
Ping Liu ◽  
Yanzhu Fan ◽  
Jing Yang ◽  
...  
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Right Hemisphere ◽  
Brain Area ◽  
Power Spectra ◽  
Low Frequency ◽  
The Right ◽  
Electroencephalogram Eeg ◽  
The Brain ◽  
Steady Velocity

ABSTRACTVisual lateralization is widespread for prey and anti-predation in numerous taxa. However, it is still unknown how the brain governs this asymmetry. In this study, we conducted behavioral and electrophysiological experiments to evaluate anti-predatory behaviors and dynamic brain activities in Emei music frogs (Nidirana daunchina), to explore the potential eye bias for anti-predation and the underlying neural mechanisms. To do this, predator stimuli (a model snake head and a leaf as a control) were moved around the subjects in clockwise and anti-clockwise directions at steady velocity. We counted the number of anti-predatory responses and measured electroencephalogram (EEG) power spectra for each band and brain area (telencephalon, diencephalon and mesencephalon). Our results showed that (1) no significant eye preferences could be found for the control (leaf); however, the laterality index was significantly lower than zero when the predator stimulus was moved anti-clockwise, suggesting that left-eye advantage exists in this species for anti-predation; (2) compared with no stimulus in the visual field, the power spectra of delta and alpha bands were significantly greater when the predator stimulus was moved into the left visual field anti-clockwise; and, (3) generally, the power spectra of each band in the right-hemisphere for the left visual field were higher than those in the left counterpart. These results support that the left eye mediates the monitoring of a predator in music frogs and lower-frequency EEG oscillations govern this visual lateralization.

Asymmetries of Sensory Functions (Spatial and Temporal Discrimination) in Normal Persons

1947 ◽  
Vol 93 (391) ◽  
pp. 318-332 ◽  
Author(s):  
H. H. Fleischhacker
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Temporal Discrimination ◽  
Mental Symptoms ◽  
The Right ◽  
The Brain ◽  
Sensory Functions

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).

Neuropsychological Rehabilitation Technique with a Chronic Schizophrenic Patient

1990 ◽  
Vol 7 (4) ◽  
pp. 179-184 ◽  
Author(s):  
Ian G. Gale
Keyword(s):  
Schizophrenic Patient ◽  
Physical Aggression ◽  
Right Hemisphere ◽  
Occipital Region ◽  
Verbal Expression ◽  
Neuropsychological Rehabilitation ◽  
Chronic Schizophrenic Patient ◽  
Neuropsychological Investigation ◽  
The Right ◽  
The Brain

Detailed neuropsychological investigation of a schizophrenic patient found a deficit in functions usually attributed to the left parieto-occipital region. Interventions designed to exercise the putatively left parieto-occipital functions (‘understanding the verbal expression of spatial relationships’) and to exercise putatively right hemisphere functions (exercises based on Edwards' — ‘Drawing on the Right Side of the Brain’) were compared. The patient demonstrated lowest levels of hallucinatory behaviour, aggressive verbal outbursts, and physical aggression during phases when right hemisphere exercises were programmed. Possible reasons for this outcome are examined.

scholarly journals Neural Basis of Depression Related to a Dominant Right Hemisphere: A Resting-State fMRI Study

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Mi Li ◽  
Hongpei Xu ◽  
Shengfu Lu
Keyword(s):  
Right Hemisphere ◽  
Inferior Frontal Gyrus ◽  
Middle Temporal Gyrus ◽  
Neural Basis ◽  
Middle Temporal ◽  
Middle Occipital Gyrus ◽  
The Right ◽  
Depressive Patients ◽  
The Brain ◽  
Left Middle

Background. In the past, studies on the lateralization of the left and right hemispheres of the brain suggested that depression is dominated by the right hemisphere of the brain, but the neural basis of this theory remains unclear. Method. Functional magnetic resonance imaging of the brain was performed in 22 depressive patients and 15 healthy controls. The differences in the mean values of the regional homogeneity (ReHo) of two groups were compared, and the low-frequency amplitudes of these differential brain regions were compared. Results. The results show that compared with healthy subjects, depressive patients had increased ReHo values in the right superior temporal gyrus, right middle temporal gyrus, left inferior temporal gyrus, left middle temporal gyrus, right middle frontal gyrus, triangular part of the right inferior frontal gyrus, orbital part of the right inferior frontal gyrus, right superior occipital gyrus, right middle occipital gyrus, bilateral anterior cingulate, and paracingulate gyri; reduced ReHo values were seen in the right fusiform gyrus, left middle occipital gyrus, left lingual gyrus, and left inferior parietal except in the supramarginal and angular gyri. Conclusions. The results show that regional homogeneity mainly occurs in the right brain, and the overall performance of the brain is such that right hemisphere synchronization is enhanced while left hemisphere synchronization is weakened. ReHo abnormalities in the resting state can predict abnormalities in individual neurological activities that reflect changes in the structure and function of the brain; abnormalities shown with this indicator are the neuronal basis for the phenomenon that the right hemisphere of the brain has a dominant effect on depression.

Using Fractal and Local Binary Pattern Features for Classification of ECOG Motor Imagery Tasks Obtained from the Right Brain Hemisphere

2016 ◽  
Vol 26 (06) ◽  
pp. 1650022 ◽  
Author(s):  
Fangzhou Xu ◽  
Weidong Zhou ◽  
Yilin Zhen ◽  
Qi Yuan ◽  
Qi Wu
Keyword(s):  
Motor Imagery ◽  
Local Binary Pattern ◽  
Right Hemisphere ◽  
Ordinary Least Squares ◽  
Superior Performance ◽  
Gradient Boosting ◽  
The Right ◽  
The Brain ◽  
Combined Feature

The feature extraction and classification of brain signal is very significant in brain–computer interface (BCI). In this study, we describe an algorithm for motor imagery (MI) classification of electrocorticogram (ECoG)-based BCI. The proposed approach employs multi-resolution fractal measures and local binary pattern (LBP) operators to form a combined feature for characterizing an ECoG epoch recording from the right hemisphere of the brain. A classifier is trained by using the gradient boosting in conjunction with ordinary least squares (OLS) method. The fractal intercept, lacunarity and LBP features are extracted to classify imagined movements of either the left small finger or the tongue. Experimental results on dataset I of BCI competition III demonstrate the superior performance of our method. The cross-validation accuracy and accuracy is 90.6% and 95%, respectively. Furthermore, the low computational burden of this method makes it a promising candidate for real-time BCI systems.

scholarly journals Artificial Intelligence to Analyze the Cortical Thickness Through Age

2021 ◽  
Vol 4 ◽  
Author(s):  
Sergio Ledesma ◽  
Mario-Alberto Ibarra-Manzano ◽  
Dora-Luz Almanza-Ojeda ◽  
Pascal Fallavollita ◽  
Jason Steffener
Keyword(s):  
Artificial Intelligence ◽  
Neural Networks ◽  
Artificial Neural Networks ◽  
Left Hemisphere ◽  
Cortical Thickness ◽  
Right Hemisphere ◽  
Unseen Data ◽  
Artificial Neural ◽  
The Right ◽  
The Brain

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.

scholarly journals EEG Asymmetries in Depressive Female Adolescents with Different Kinds of Auto-Aggressive Behavior

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
Keyword(s):  
Aggressive Behavior ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Spectral Power ◽  
Quantitative Eeg ◽  
Female Adolescents ◽  
Self Injury ◽  
Increased Risk ◽  
The Right ◽  
The Brain

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.

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