Gamma band oscillations in parietooccipital areas during performance of a sensorimotor integration task: a qEEG coherence study

Abstract

This study aimed to elucidate cortical mechanisms involved in anticipatory actions when 23 healthy right-handed subjects had to catch a free falling object through quantitative electroencephalogram (qEEG). For this reason, we used coherence that represents a measurement of linear covariation between two signals in the frequency domain. In addition, we investigated gamma-band (30-100 Hz) activity that is related to cognitive and somatosensory processes. We hypothesized that gamma coherence will be increase in both parietal and occipital areas during moment after ball drop, due to their involvement in manipulation of objects, visuospatial processing, visual perception, stimuli identification and attention processes. We confirmed our hypothesis, an increase in gamma coherence on P3-P4 (t= -2.15; p=0.033) and PZ-OZ (t= -2.16; p=0.034) electrode pairs was verified for a paired t-test. We conclude that to execute tasks involving anticipatory movements (feedforward mechanisms), like our own task, probably, there is no need of a strong participation of visual areas in the process of information organization to manipulate objects and to process visuospatial information regarding the contact hand-object. Key words: catching, coherence, gamma, qEEG, sensorimotor integration.Oscilações na banda gama em áreas parieto-occipitais durante desempenho de uma tarefa sensório-motora: um estudo de coerência na EEGq RESUMO Este estudo teve como objetivo elucidar os mecanismos corticais envolvidos em ações antecipatórias quando 23 indivíduos saudáveis destros tinham que apreender um objeto em queda livre, através da eletroencefalografia quantitativa (EEGq). Por esta razão, usamos a coerência que representa a covariação linear entre dois sinais no domínio da frequência. Além disso, investigamos a atividade da banda gama (30-100 Hz), que está relacionada à processos cognitivos e somato-sensoriais. Nossa hipótese é que a coerência de gama estará aumentada em ambas as áreas parietais e occipitais durante o momento pós-queda da bola, devido ao seu envolvimento na manipulação de objetos,

Gamma absolute power reveals activation of motor areas after hand immobilization

“…Frontal cortical areas are associated motivation, planning, reasoning, problem solving and execution of voluntary movements. 25,26 Specifically F3 and F4 derivations (middle frontal gyrus) correspond to manual planning areas; 27,28 F3 is associated with the cortical area corresponding to right hand (the immobilized hand),while F4 associated with the left hand. Increased gamma band absolute power at F3 after hand immobilization indicates more activation at this cortical region in order to elicit the index finger movement required by the task.…”

Comparative Analysis Electroencephalographic of Alpha, Beta and Gamma Bands of a Healthy Individual and One with Hemiparesis

“…According to Teixeira, its frequency range is 30–100 Hz16 ) . However, Uhlhaas demonstrated frequencies from 60 to 200 Hz, which were correlated to specific cognitive functions8 ) .…”

Decoding cortical response during motor tasks using brain connectivity

“…Some studies have suggested that the EEG gamma band is responsible for the communication between cortical areas during the performance of sensorimotor integration tasks. These findings indicate that gamma plays an essential role in the early stages of information processing and of sensorimotor integration process [22]. Oscillations in gamma can be related to cortical operation during recognizing of familiar objects and to the efficiency of forthcoming of sensory information in the relevant sensory cortical areas.…”