Electroencephalogram Correlates of Higher Cortical Functions

Abstract

By means of two-stage, nonlinear multivariate pattern recognition, electroencephalograms (EEG's) were analyzed during performance of verbal and spatial tasks. Complex scalp distributions of theta-, beta-, and, to a lesser extent, alpha-band spectral intensities discriminated between the two members of a pair of tasks, such as writing sentences and Koh's block design. Small EEG asymmetries were probably attributable to limb movements and other uncontrolled noncognitive aspects of tasks. Significant EEG differences beteeen cognitive tasks were eliminated when controls for inter-task differences in efferent activity, stimulus characteristics, and performance-related factors were introduced. Each controlled task was associated with an approximately 10 percent reduction, as compared with visual fixation, in the magnitude of alpha- and beta-band spectral intensity. This effect occurred bilaterally and was approximately the same over occipital, parietal, and central regions, with some minor difference over the frontal region in the beta band. With these controls, no evidence for lateralization of different cognitive functions was found in the EEG.

Mental Effort‐Related EEG Modulation During Video‐Game Play: Comparison Between Juvenile Subjects with Epilepsy and Normal Control Subjects

“…Decreased alpha in the high-load task is consistent with the notion that the amplitude of this signal is inversely related to the proportion of cortical neurons involved with task performance. Similar patterns of effort-related modulation of the EEG have been found in numerous other investigations (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). Although spectral components of healthy adults' EEG have been shown to be sensitive to the mental effort associated with computer-based laboratory tasks, few data exist concerning whether the EEGs of juvenile subjects playing commercial video games will exhibit the similar patterns.…”

“…The peak amplitude at electrode site F, (6-7 Hz) was extracted to represent frontal midline theta in each subject. Average power across a 1-Hz band was used to characterize the alpha rhythm at electrode site 0, (9)(10)(11)(12) Hz) and the mu rhythm at electrode site C, (10)(11)(12)(13). A 3 (Load: resting x watching x playing) by 2 (Group: patient x control) ANOVA on absolute power values yielded no significant effect of group, or Group-by-Load interactions, at any of the measured frequencies.…”

Staggered spondaic word test in epileptic patients

“…According to several authors, [14][15][16][17][18][19][20] dendritic and neuronal losses are always present in epileptic patients. These losses are independent of crisis type, and if we consider the anatomical and histopathological disorders responsible for poor performance by epileptic patients in the auditory skills evaluated in the SSW test, these authors' findings would explain such performance observed in both groups of epileptic patients studied here.…”

Biocybernetic Analysis of a Hybrid Workload Model.

“…Electroencephalography (EEG) correlates of workload have focused upon P300 as a measure of central processing (Israel et * al., 1980) and spatial and temporal dynamic patterns of evoked potentials during mental work (Gevins et al, 1979(Gevins et al, , 1981(Gevins et al, , 1983. These techniques require steady-state workload conditions for averaging.…”