EEG spectral cohrence inter and intrahemispheric during catching object fall task

Portella

et al. 2007

Self Cite

-the main goal of the present study was to analyze theta asymmetry through quantitative electroencephalography (qEEG) when individuals were exposed to a sequential motor task, i.e. catching a ball. the sample was composed of 23 healthy subjects, male and female, between 25 and 40 years of age. A two-way factor AnovA was applied to compare pre and post moments related to the balls' drop and scalp regions (i.e., frontal and parieto-occipital cortices). the first analysis of the frontal region compared electrodes in the left, right and left/right hemispheres combined, with the frontal midline electrode (FZ) included in the analysis. the results showed moment and region main effects. the second analysis compared left versus right hemisphere without the FZ site. the findings demonstrated an interaction effect between moment and region. the first parieto-occipital analysis, comparing left, right and central regions, with PZ included in all regions, showed main effects of moment and region. the second analysis, comparing left, right (without Pz) and central regions strictly demonstrated a region main effect. thus, we observed an asymmetric pattern in the frontal cortex (i.e., planning and response selection) when the subjects were waiting for the balls' drop. Moreover, the left hemisphere seems to engage differently from the other regions when the central nervous system needs to prepare for a motor action. on the other hand, the parieto-occipital cortex, which is related to attentive processes, demonstrated a more asymmetric activity towards the right region which implies a participation of this area in cognitive strategies in this particular task. taken together, we concluded that the adopted experimental approach can be useful to explore several others directions combining sensorimotor integration tasks with different pathologies, such as depression, Alzheimer's and Parkinson's diseases.KEy words: motor control, sensory-motor integration, asymmetry, qEEG.Assimetria cortical: apreensão de um objeto em queda livre rEsuMo -o objetivo do presente experimento foi avaliar medidas de assimetria na banda teta através da electroencefalografia quantitativa (EEGq) durante a realização da atividade motora de apreensão de uma bola em queda livre. A amostra constituiu-se de 23 sujeitos saudáveis de ambos os sexos, faixa etária entre 25 e 40 anos. AnovA two-way foi utilizada para comparar os momentos pré e pós relacionados à queda da bola, e às regiões do escalpo (córtex frontal e parieto-occipital). A primeira análise da região frontal comparou eletrodos nos hemisférios esquerdo, direito e esquerdo/direito combinados, incluindo na análi-se o eletrodo frontal mediano (FZ). o resultado demonstrou um efeito principal para momento e região. A segunda análise comparou os hemisférios direito e esquerdo, sem o eletrodo FZ. neste achado verificouse um efeito principal para a interação entre os fatores momento e região. A primeira análise realizada na região parieto-occipital comparou as regiões esquerda, direita e central, com PZ...

Section: Resultssupporting

confidence: 93%

Cortical asymmetry: catching an object in free fall

Velasques

Portella

et al. 2007

Self Cite

“…An electromagnetic system, made of two solenoids, was positioned ahead of the subjects in order to send information about the pre and post fall time to the computer 12 . results demonstrated a theta absolute power increase in the post fall period, when compared to the pre fall period.…”

Section: Resultsmentioning

confidence: 99%

“…the intervals favored the recovery of the active limb, avoiding muscular fatigue. the qeeG acquisition occurred during 2 seconds before the ball fall and 2 seconds after the ball fall 12 .…”

Section: Methodsmentioning

confidence: 99%

Changes in quantitative EEG absolute power during the task of catching an object in free fall

Portella

Silva

et al. 2007

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-the aim of this study was to verify changes in absolute power (qEEG), in theta, during the catch of a free falling object. the sample consisted of 10 healthy individuals, of both genders, with ages between 25 and 40 years. A three-way ANOVA followed by Post-Hoc analysis was applied. the results demonstrated main effects for time and position. In conclusion, a motor task that involves expectation produces deactivation of non-relevant areas in the ipsilateral hemisphere of the active limb. On the other hand, the patterns of results showed activation in areas responsible for planning and selection of motor repertories in the contralateral hemisphere.Key wOrds: absolute power, qeeG, planning, sensorimotor integration.Mudanças na potência absoluta no EEG quantitativo durante tarefa de apreensão de um objeto em queda livre resumO -O objetivo deste estudo foi verificar mudanças na potência absoluta (EEGq), em teta, durante a pegada de objeto em queda livre. A amostra consistiu de 20 indivíduos saudáveis, de ambos os gêneros, com idade entre 25 e 40 anos. Foi utilizada uma ANOVA three-way seguida de uma análise Post-Hoc. Os resultados demonstraram efeito principal para momento e posição. concluindo, uma tarefa motora que envolve expectativa produz desativação de áreas não-relevantes no hemisfério ipsilateral do membro ativo. Por outro lado, o padrão dos resultados mostrou ativação em áreas responsáveis por planejamento e seleção de repertórios motores no hemisfério contralateral.PAlAvrAs-chAve: potência absoluta, eeGq, planejamento, integração sensório-motora. motor behavior is the product of a fine integration between cortical and peripheral components associated to afferent information. the central nervous system (cNs) captures, identifies and processes sensory stimuli in order to prepare and adjust motor behavior 1 . the prefrontal cortex (PFc) is an integration cortex. It is considered neither a sensory nor a motor cortex; it is an association region, providing integration sensory stimuli to motor centers 2,3 . the PFc is involved in cognition, attention maintenance, planning and organization, including the capacity to follow certain thought sequences and behavior strategy choices 4 . Plastic alterations might occur in this area regarding motor reactions (reaction time, anticipatory movements and motor learning), which might lead to performance and gesture precision improvement 5 . Quantitative electroencephalography (qEEG) has made possible the elucidation of cognitive processes and motor learning 6,7 . specific electroencephalographic variables are particularly related to such processes. Absolute power, defined as total energy intensity of an electrode on a certain region at different frequency bands 8 . therefore, the present study examined the theta band (4-7 hz), due to its relation with attention processes, particularly, sustained attention 9 . Previous experimental data showed an association between theta and cognitive and visual-

“…The qEEG acquisition was collected using the international 10/20 system 10 during 2 seconds before and after the ball's drop. This methodology has already been utilized in other experiment conducted in the Brain Mapping and sensorimotor Integration laboratory 11 . It was also done an electromyography (EMG) analysis in the experiment.…”

Section: Methodsmentioning

confidence: 99%

Posterior parietal cortex role in a sensorimotor task performance

Nader

Cunha

et al. 2008

Self Cite

-This study aimed to elucidate electrophysiological and cortical mechanisms involved in anticipatory actions when individuals had to catch balls in free drop; specifically through quantitative electroencephalography (qEEG) alpha absolute power changes. The sample was composed for 23 health subjects, both sexes, with ages varying between 25 and 40 years, absence of mental and physical illness, right handed and don't make use of any psychoactive or psychotropic substance at the time of the study. The experiment consisted of a task of catching balls in free drop. The three-way ANOVA analysis demonstrated an interaction between moment and position factors in left parietal posterior cortex (PPC) (p=0.001). Through the experimental task employed, this area demonstrated a differentiated activity involving expectation, planning and preparedness in the ball's drop task.KEy words: absolute power, catch, qEEG, sensorimotor integration. Papel do córtex parietal posterior na realização de uma tarefa sensório-motoraResumo -o estudo tentou elucidar mecanismos eletrofisiológicos e corticais envolvidos em ações antecipatórias quando os sujeitos testados tiveram que apreender bolas em queda livre; especificamente através de mudanças na potência absoluta na banda alfa da eletrencefalografia quantitativa (EEGq). A amostra foi composta por 23 sujeitos sadios, ambos os sexos, idade entre variando entre 25 e 40 anos, sem comprometimento físico e mental, destros, e não fazer uso de nenhuma substância psicoativa ou psicotrópicos até o momento do estudo. o experimento consistiu de uma tarefa de apreensão de bolas em queda livre. A análise three-way ANOVA demonstrou uma interação entre os fatores momento e posição no córtex parietal posterior (CPP) esquerdo (p=0,001). Através da tarefa experimental empregada, esta área demonstrou uma atividade diferenciada envolvendo expectativa, planejamento e prontidão na tarefa de queda de bolas.PAlAvrAs-ChAvE: potência absoluta, apreender, EEGq, integração sensório-motora. The posterior parietal cortex (PPC) plays a crucial role in relation to motor planning based on sensory information. human functional magnetic resonance imaging (fMrI) experiments and electrophysiological recordings in nonhuman primates have shown that the PPC is neither sensory nor motor purely, but it is an area that encodes cognitive functions related to action 1,2 . The presence of sensory and motor specific representations together with high-level cognitive signals suggests that the PPC plays an important role for decision making related to action 2 .such representations are elementary components in the preparation and adjustment of a motor act and they take part in the integration among different and specialized centers in the final movement production 3 . This process occurs through sensorimotor integration, when sensory information is integrated by central nervous system to attend to motor programs.Catching an object is a complex movement which involves not only programming but also effective motor coordination. suc...