Influence of emotional words on human visual recognition and brain asymmetry.

To investigate the number of correct responses, the reaction time and the event-related brain potentials, effects of positive and negative verbal reinforcement on the visuo-spatial recognition of simple geometric figures, in condition of backward masking, were studied in healthy subjects and patients with chronic alcoholism. It was found that in performing the mental construction of geometrical figures from pairs of fragments, the number of correct responses by alcoholics, unlike the control group, was greater and the reaction time was lesser in the tests after positive verbal reinforcement than after negative verbal reinforcement. The latter in healthy subjects produce reduction of the latency and increase in the amplitude of N200-P300 potentials, particularly in the right parietal lobe. These changes were not observed in alcoholics. Moreover, negative verbal reinforcement, unlike positive, produced an emotional reaction, which underlay the worsening in recognition by alcoholics. The patients' lesser ability to perform the visuo-spatial tasks could be explained by the general reduction in the event-related potentials and the disappearance of the brain asymmetry. The verbal feedback mechanisms of reinforcement play an important role in the dynamic changes in the hemispheric lateralization of the human brain.