Early gamma response in human neuroelectric activity is correlated with neuropsychological test scores

The goal of this study was to investigate whether early, time-locked 'sensory' gamma band response is correlated with a set of scores derived from neuropsychological tests. Neuroelectric responses were obtained under active auditory oddball paradigm. Of 67 reportedly healthy adults, 35 displayed time-locked early gamma, G (+), and 24 did not, G (-). Out of 52 neuropsychological test scores, G (+) and G (-) groups differed on the basis of Wisconsin Card Sorting Test, Wechsler Memory Scale-Revised and Serial Digit Learning Test scores. Results of logistic regression analysis was statistically reliable (overall success rate of prediction: 93.33%). The results showed that early gamma response can be classified on the basis of neuropsychological test performance and is thus associated with higher cognitive functions, supporting the view that brain integrates bottom-up with top-down processing.