Visual field and hemisferic differences in word naming and picture naming tasks: rt and eeg studies

Abstract

The study explores visual field differences in word naming and picture naming tasks aiming to reveal what factors influence reaction time in processing of different grammatical classes with different word characteristics, and how. The study also tried to look at gamma behavior in response to visual field and grammatical class conditions and word characteristics. Results of word naming reaction time experiment suggested differential brain strategies in activation of different information sources depending on the field of presentation. The study also showed that regression analysis may be of use in addition to analysis of variance. Results of picture naming reaction time experiment showed not so clear-cut boundaries in the patterns of processing as in word naming experiment. The results were attributed to the overall complexity of the task and, possibly, influence of other factors. Word naming and picture naming experiments on gamma behavior revealed both differences and similarities of word and picture processing within- and between subjects. In addition, analysis of variance and regression analysis suggested that gamma oscillations as a measure of cognitive process might be more informative than reaction time. It seems that gamma may show two different processing strategies: an activation strategy and a processing difficulty strategy, the latter being analogous to reaction time.