A cross-sectional study of influence of cerebral dominance on cardiovascular responses to autonomic stressor tests in adolescents

Background: Hand preference is perhaps the most obvious behavioral asymmetry observed in humans and is related to cerebral dominance. Animal and human studies have shown that cerebral cortex has a definite role in regulation of cardiovascular autonomic activity. Each hemisphere exhibits differential control over dynamics of heart especially the sympathetic activity is controlled by right hemisphere insula in particular. Hence, the present study was conducted to evaluate influence of cerebral dominance (handedness) on cardiovascular responses such as heart rate (HR) and blood pressure (BP) indices to autonomic stressor tests in the left and right hander adolescents. Aims and Objectives: The aim of the study was to evaluate the differences in cardiovascular responses in the left and right handers to autonomic stressor tests. Materials and Methods: The present cross-sectional study was conducted in 35 right and 35 left hander students of age group 16–20 years. Autonomic stressor tests used in the study were handgrip dynamometry and cold pressor test (CPT). Results: The right and left handers had similar baseline values of BP and HR. All the subjects responded to Autonomic function tests by increased BP and HR from baseline. The absolute BP values and change in BP from baseline were significantly higher in the left than right handers both during and after the tests. HR values showed significant differences in peak values during both the tests. Visual analog score was similar during CPT in both groups. Conclusion: The HR and BP responses to autonomic stressor tests are higher in the left handers than right handers supports the fact that the right hemisphere has more influence on sympathetic activity of heart.

Do Hand Preference Has A Tie-up With Cognitive Ability? A Cross-sectional Study Among The Adolescent School Students

Introduction: Handedness is perhaps the most overt reflection of lateralization of the central nervous system inhumans. Humans show a strong and population-level bias toward using one hand rather than the other formanual activities, which is unusual among mammals. As handedness is biologically and genetically linked, soit has various effects on one’s behaviour and abilities. Since intelligence has an impact on human behaviour,intelligence is considered an important aspect. Language is a system by communication. The meaning of anythingis created by using symbols and our intelligence can be communicated to others by reading, speaking andwriting. Researchers argue that right handers are more intelligent than the left handers and this is the reasonbehind changing the handedness of the children. This present study aims at finding the authencity of thisopinion.Aim: We assessed the cerebral dominance and association between handedness and intelligence among schoolstudents.Method: Lateral preference inventory for handedness and Raven’s Standard Progressive Matrix Test forintelligence.Statistical method used: IBM statistics-20. The P-Values less than or equal to 0.05 (<0.05) were considered asstatistically significant.Result: Statistical significance results were observed between left and right handers in terms of gender, age andeducational standards.Conclusion: Left handed students were more intelligent than right handed students. Furthermore if more accessoriesare specially designed for left handers, they can achieve much more better.

Reliability and Validity of the Comprehensive Limb and Oral Apraxia Test: Standardization and Clinical Application in Korean Patients With Stroke

OBJECTIVE: To develop and standardize the Limb and Oral Apraxia Test (LOAT) for Korean patients and investigate its reliability, validity, and clinical usefulness for patients with stroke. METHODS: We developed the LOAT according to a cognitive neuropsychological model of limb and oral praxis. The test included meaningless, intransitive, transitive, and oral praxis composed of 72 items (56 items on limb praxis and 16 items on oral praxis; maximum score 216). We standardized the LOAT in a nationwide sample of 324 healthy adults. Intra-rater and inter-rater reliability and concurrent validity tests were performed in patients with stroke. We prospectively applied the LOAT in 80 patients and analyzed the incidence of apraxia. We also compared the clinical characteristics between the apraxia and non-apraxia groups. RESULTS: The internal consistency was high (Cronbach’s alpha=0.952). The inter-rater and intra-rater reliability and concurrent validity were also high (r=0.924–0.992, 0.961–0.999, and 0.830, respectively; p0.05). Among the 80 patients with stroke, 19 (23.8%) had limb apraxia and 21 (26.3%) had oral apraxia. Left hemispheric lesions and aphasia were significantly more frequently observed in the limb/oral apraxia group than in the non-apraxia group (p<0.001). CONCLUSION: The LOAT is a newly developed comprehensive test for limb and oral apraxia for Korean patients with stroke. It has high internal consistency, reliability, and validity and is a useful apraxia test for patients with stroke.

Evaluación de parámetros de banda ancha en la determinación de dominancia cerebral durante la hipnosis / Evaluation of wide band parameters in the determination of cerebral dominance during hypnosis

Se realizó un estudio cuasiexperimental de 21 estudiantes que cursaban la carrera de medicina, los cuales se encontraban en estado de hipnosis, atendidos en el Hospital General Docente Dr Juan Bruno Zayas Alfonso de Santiago de Cuba, desde septiembre del 2014 hasta junio del 2015, con vistas a identificar las medidas espectrales de banda ancha sensibles en la determinación de la dominancia cerebral durante dicho estado. Entre las variables analizadas figuraron: nivel de profundidad hipnótica, medidas espectrales de banda ancha y derivación. Se utilizó el estadígrafo false discovery rate como prueba de hipótesis para validar la información estadística y el análisis de varianza multivariado Manova. Los resultados revelaron que el poder relativo theta resultó ser la medida espectral con modificaciones más significativas y mostró un predominio discreto de la energía en el hemisferio izquierdo. Se concluyó que este hallazgo tuvo lugar como consecuencia de las tareas indicadas durante la hipnosis

A quasi-experiment of 21 students that were studying the medicine career, who were in hypnosis state, assisted in Dr Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba, was carried out from September, 2014 to June, 2015, aimed at identifying the wide band spectral measures sensitive in the determination of cerebral dominance during this state. Among the analyzed variables we can mention: level of hypnotic depth and spectral measures of wide band and derivation. The false discovery rate stadigraph was used as hypothesis test to validate the statistical information and the Manova multivaried analysis of variance. The results revealed that theta relative power was the spectral measure with more significant modifications and showed a discreet prevalence of energy in the left hemisphere. It was concluded that this finding took place as a consequence of the given tasks during hypnosis

Acquired dysgraphia in adults following right or left-hemisphere stroke / Disgrafias adquiridas em adultos após acidente vascular cerebral unilateral nos hemisférios direito e esquerdo

Objective: This study aimed to assess the strengths and difficulties in word and pseudoword writing in adults with left- and right-hemisphere strokes, and discuss the profiles of acquired dysgraphia in these individuals. Methods: The profiles of six adults with acquired dysgraphia in left- or right-hemisphere strokes were investigated by comparing their performance on word and pseudoword writing tasks against that of neurologically healthy adults. A case series analysis was performed on the patients whose impairments on the task were indicative of acquired dysgraphia. Results: Two patients were diagnosed with lexical dysgraphia (one with left hemisphere damage, and the other with right hemisphere damage), one with phonological dysgraphia, another patient with peripheral dysgraphia, one patient with mixed dysgraphia and the last with dysgraphia due to damage to the graphemic buffer. The latter patients all had left-hemisphere damage (LHD). The patterns of impairment observed in each patient were discussed based on the dual-route model of writing. Conclusion: The fact that most patients had LHD rather than right-hemisphere damage (RHD) highlights the importance of the former structure for word processing. However, the fact that lexical dysgraphia was also diagnosed in a patient with RHD suggests that these individuals may develop writing impairments due to damage to the lexical route, leading to heavier reliance on phonological processing. Our results are of significant importance to the planning of writing interventions in neuropsychology.

Objetivo: Investigar aspectos preservados e dificuldades na escrita de palavras e pseudopalavras em adultos que sofreram acidente vascular cerebral (AVC) à esquerda e à direita e discutir os perfis de disgrafia adquirida nesses indivíduos. Métodos: Investigaram-se perfis de disgrafia adquirida a partir da avaliação das habilidades e dificuldades na escrita de palavras e pseudopalavras de seis adultos que sofreram AVC no hemisfério direito (LHD) e no hemisfério esquerdo (LHE), comparados a adultos neurologicamente saudáveis. Realizou-se análise de séries de casos com os pacientes que apresentaram desempenho deficitário na escrita de palavras, que indicavam a presença de uma disgrafia adquirida. Resultados: Foram identificados dois casos com disgrafia lexical (sendo um com LHE e outro com LHD), um caso com disgrafia fonológica, um com disgrafia periférica, um com disgrafia mista e um com disgrafia por déficit no buffer grafêmico, todos estes com LHE. Destacou-se nesse estudo a heterogeneidade das habilidades linguísticas dos casos clínicos, discutidas de acordo com o modelo cognitivo de dupla-rota de escrita. Conclusão: O maior prejuízo encontrado nos pacientes com LHE ressalta a importância desse hemisfério cerebral para o processamento da escrita de palavras. A presença de um caso com LHD com perfil de disgrafia lexical destaca a necessidade de melhor estudar o papel do hemisfério direito no processamento de palavras. Espera-se que esse estudo contribua para o planejamento de estratégias de intervenção neuropsicológica direcionadas à escrita de palavras.

Análisis correlacional del perfil de dominancia cerebral de estudiantes de ciencias de la salud y estudiantes de ciencias sociales de la Universidad Colegio Mayor de Cundinamarca / Correlational Analysis of the profile of cerebral dominance of students of the Health Sciences and students of the Colegio Mayor de Cundinamarca University

El presente artículo explicita los resultados correspondientes al análisis correlacional de los perfiles de dominancia cerebral o estilos de pensamiento de los estudiantes de Ciencias de la Salud y Ciencias Sociales de la UCMC, los cuales forman parte del proyecto conjunto Representaciones, organización conceptual y estilos de pensamiento, en el marco del Convenio de Cooperación Académica IISUE-UNAM (México) y La UCMC, Bogotá-Colombia, liderado por el Dr. Miguel Ángel Campos Hernández. Lo anterior tomando como base el modelo de Cerebro Total de Herrmann y los estudios recientes de Omar Gardié. Los estudiantes de Ciencias de la Salud presentan mayor preferencia de los cuadrantes cortical izquierdo y límbico izquierdo A-B; es decir, tienen predilección por el hemisferio izquierdo. Los estudiantes de Ciencias Sociales presentan mayor predisposición en los cuadrantes límbico izquierdo y límbico derecho B-C; es decir, tienen mayor tendencia por el sistema límbico. Con los resultados de esta investigación se verificó la hipótesis en torno de la escasa utilización de las posibilidades creativas y del desarrollo del cerebro total de los grupos sometidos a estudio. De igual modo, se identificó la manera como los perfiles de dominancia de los estudiantes se relacionan con las disciplinas que han seleccionado en su formación.

This article reports the results corresponding to the correlational analysis profiles of cerebral dominance or thinking styles of the students in Health Sciences and Social Sciences of the UCMC, which are part of the joint project Representations, conceptual organization and thinking styles, in the framework of the Convention of Academic Cooperation IISUE-UNAM (Mexico) and the UCMC, Bogotá, Colombia, led by Dr. Miguel Ángel Campos Hernández. The above based on the model of Total Brain of Herrmann and recent studies of La Gardie. The Health Sciences students have a greater preference for the left cortical and limbic quadrants A and B; i.e., they have a preference for the left hemisphere. Social Science students have a higher preference for the left limbic and right limbic quadrants B and C; that is, they have greater preference for the limbic system. The results of this investigation proved the hypothesis about the low use of the creative possibilities and the development of the total brain of the groups subject to study. Similarly, it was found that the profiles of dominance of the students are related to the disciplines that have been selected in their training.

Physiology of nostril breathing exercises and its probable relation with nostril and cerebral dominance: A theoretical research on literature

This article discuss about scientific basis of benefits of practicing slow pranayama, especially alternate nostril breathing pranayama. It explains the basis of benefit of alternate nostril breathing exercises and its probable relation with nasal cycle, cerebral dominance and autonomic nervous system. The airflow through one nostril is greater than next at any point of time which later switches to another. This is called nasal cycle. The nasal cycle lasts from 30 minutes to 2-3 hours. The nasal cycle occurs naturally. This nasal cycle is related with the cerebral dominance. When one nostril is dominant, the contra lateral hemisphere is active. The right nostril breathing leads to increased sympathetic activity while left nostril breathing decreases sympathetic activity and increases parasympathetic tone. So it has been speculated that these three phenomenon viz. nasal cycle, cerebral dominance and autonomic activities are correlated. This review also suggests that practicing alternate nostril breathing (Nadisodhan pranayma) regularly keeps the two hemispheres active and balances the sympathetic and parasympathetic activities in the body. Sympathetic or parasympathetic activity alternates automatically in our body which is important for our survival. Due to our hectic and stressful life, this naturally occurring alternate breathing cycle gets disrupted and we suffer from different ailments. These ailments are due to imbalance of autonomic nervous system which can be resolved by practicing alternate nostril breathing, the Nadisodhan pranayama. It’s just like returning back to nature.

Tomada de decisão no IGT: estudo de caso pós-AVC de hemisfério direito versus esquerdo / Decision making in IGT: a case study of post-CVA of left versus right hemisphere / Toma de decisión en el IGT: estudio de caso post-AVC de hemisferio derecho versus isquierdo

Investigou comparativamente o processo de tomada de decisão de dois adultos pós-AVC unilateral e verificar o papel da lateralidade hemisférica na performance do Iowa Gambling Task (IGT). Participaram um adulto com lesão de hemisfério direito (LHD) e outro com lesão de hemisfério esquerdo (LHE), ambos pós-AVC isquêmico subcortical. O IGT foi utilizado para avaliar a tomada de decisão. Os pacientes apresentaram um desempenho adequado no IGT, demonstrando ter uma boa capacidade de tomar decisão. No entanto, somente o paciente com LHD apresentou uma curva sugestiva de aprendizagem. Esses dados indicam que uma lesão subcortical independente do hemisfério pode não interferir no desempenho do IGT. Sugere-se que estudos de grupos sejam conduzidos buscando comparar pacientes com lesão frontal e não-frontal, auxiliando na caracterização do processo de tomada de decisão na população com lesão vascular unilateral.

This study aimed at conducting a comparative investigation of the decision-making process of two post-unilateral CVA adults as well as verifying the role of hemispheric laterality in the performance of Iowa Gambling Task (IGT). One adult with right hemisphere damage (RHD) and another with left hemisphere damage (LHD), both following a subcortical ischemic post-CVA. The IGT was used to evaluate the decision making. Patients had appropriate performance on the IGT suggesting a general good ability to make decisions. However, only the patient with LHD presented signs of ascendant learning curve. Conclusion: These data indicate that a subcortical lesion independent of the hemisphere may not influence on the IGT performance. It is suggested that comparative studies of groups should be conducted in order to compare patients with frontal and non-frontal lesions, helping to characterize the decision-making process in population with unilateral vascular damage.

Este estudio investiga comparativamente el proceso de toma de decisión de dos adultos post-AVC unilateral y verifica el papel de la lateralidad hemisférica en la performance del Iowa Gambling Task (IGT). Participaron un adulto con lesión de hemisferio derecho (LHD) y otro con lesión de hemisferio izquierdo (LHE), ambos post-AVC isquémico subcortical. El IGT fue utilizado para evaluar la toma de decisión. Los pacientes presentaron un desempeño adecuado en el IGT, demostrando una buena capacidad de tomar decisiones. Sin embargo, solamente el paciente con LHD presentó una curva sugestiva de aprendizaje. Esos datos indican que una lesión subcortical independiente del hemisferio puede no interferir en el desempeño del IGT. Se sugiere que estudios comparativos de grupos sean conducidos buscando comparar pacientes con lesión frontal y no-frontal, auxiliando en la caracterización del proceso de toma de decisión en la población con lesión vascular unilateral.

Study of handedness and facial asymmetry in teenagers.

Aim of this study was to investigate the distribution and frequencies of facial asymmetry, handedness, arm folding, and digital interlocking. It was also intended to study the correlation between the different functional traits. 200 healthy co-operative volunteers between the age group of 13 & 15 years were selected for the study. Subjects with any deformity of upper limbs & those with the history of injury to vii cranial nerve were excluded from the study. Personal data was collected from the subjects, by providing them a questionnaire, in which they also mentioned whether any of the family members was left handed, if so, their relation to the student. Various tests were conducted to determine handedness & the asymmetry in the face, arm folding, & digital interlocking. Data collected was subjected to tabulation & was subjected to statistical analysis & tested for statistical significance. Chi square test was used with paired T test. Male subjects exhibit a highly significant correlation between handedness and digital interlocking (P<0.01). Female subjects show a highly significant correlation between handedness and digital interlocking (P<0.005). Highly significant correlation exists between digital interlocking and arm folding in both sexes (P<0.0001). Both males and females, exhibit a significant correlation between handedness and vertical wrinkling of the forehead (P<0.05), as well as functional preference of other groups of facial musculatures i.e. winking (P<0.05), and lateral movement of angle of mouth (P<0.01). No significant correlation was seen between facial musculature and sex of the individual. Females showed higher preponderance of left handedness. Significant correlation exists between handedness and the following parameters; digital interlocking, and facial asymmetry.

Hemispheric specialization for communicative processing: neuroimaging data on the role of the right hemisphere

Neuropsychology has traditionally studied language emphasizing the exclusive control of the left hemisphere of the brain over this process. With the growing development of this area in psychology and the availability of neuroimaging techniques, a critical analysis of the traditional concept of cerebral dominance for language and of the bases of the neurobiological representations of this cognitive function is crucial. In this context, this review aims to investigate evidence brought by neuroimaging studies on the role of the right hemisphere in communicative processing in healthy individuals. Data suggest a co-activation of brain hemispheres in this processing, with an important contribution given by the right hemisphere in discursive, pragmatic-inferential, and prosodic processing.

Language Lateralization in Patients with Temporal Lobe Epilepsy : A Comparison between Volumetric Analysis and the Wada Test

OBJECTIVE: Determining language lateralization is important for the presurgical evaluation of patients with medically intractable epilepsy. The Wada test has been the gold standard for lateralization of language dominance before epilepsy surgery. However, it is an invasive test with risk, and have some limitations. METHODS: We compared the volumetric analysis with Wada test, and studied the clinical potential of volumetric analysis to assess language laterality in large surgical candidates with temporal lobe epilepsy (TLE). To examine the efficacy of volumetric analysis to determine language lateralization during presurgical evaluation, we compared the volumetric analysis of the bilateral planum temporale with the results of Wada test in 59 patients with chronic intractable TLE (rTLE, n=32; lTLE, n=27) who underwent epilepsy surgery. We measured the gray matter volumes of planum temporale (PT) of each patients using the VoxelPlus2 program (Mevisys, Daejeon, Korea). RESULTS: Overall congruence of the volumetric analysis with the Wada test was 97.75% in rTLE patients and 81.5% in lTLE patients. There were more significant leftward asymmetry of the PT in rTLE patients than lTLE patients. In lTLE patients, relatively high proportion (37%) of the patients showed bilateral or right hemispheric language dominance. CONCLUSION: These results provide evidence that the volumetric analysis of the PT could be used as an alternatives in language lateralization. Also, the results of the Wada test suggested that there was considerable plasticity of language representation in the brains of patients with intractable TLE and it was associated with an earlier age of brain injury.

Effect of Calculation Task on the Regional Cerebral Blood Flow Velocity: a Transcranial Doppler Study

Blood flow velocity changes induced by the focal brain activation can be assessed by using Transcranial Doppler sonography (TCD). To explore the hemispheric dominant hemodynamic effect by performing calculation, we applied TCD technique to detect cerebral blood velocity asymmetry. METHODS Twenty healthy right-handed subjects were tested. We measured mean flow velocities (MFV) in the middle and posterior cerebral arteries (MCA, PCA). Photic stimulation was given separately as a control task for calculation. RESULTS While the photic stimulation increased the blood velocity only in PCAs, performing calculation increased the velocity in MCAs. Right-left difference was noted by performing calculation with greater increase in left MCA (right: 8.8 %; left: 21.2 %). CONCLUSION Application of TCD enabled us to measure the hemodynamic changes supporting the left hemispheric dominance of calculation task. Futhermore, increase in non-dominant right hemisphere suggests the functional interaction of cerebral activity.