Are lateral differences in word processing modulated by concreteness, imageability, both, or neither?

The classic right visual field superiority for the processing of words by normal subjects is reduced when stimuli are highly imageable or concrete. Given that these two properties are correlated, imageability and concreteness are tested separately in order to decide which is determinant. In the first experiment, 16 normal subjects were given a lexical decision task with laterally visually displayed stimuli (360 items); in the second experiment, 16 other normal subjects were given a task of reading laterally displayed words (180 items). In both experiments, the usual right field advantage emerged. It was affected neither by imageability nor by concreteness in the first experiment. In the second, the right field superiority appeared, except for highly imageable words, in males only, but this interaction was not clearly interpretable. Analysis of errors suggests that the right hemisphere could be sensitive to the imageability of words and the left to their concreteness.