The hemispheric lateralization for processing geometric word/shape combinations: the Stroop-shape effect.

The authors conducted 4 experiments to test whether hemispheric lateralization occurs for the processing of geometric word-shape combinations. In 3 experiments, participants responded to geometric shapes combined with geometric words (square, circle, triangle). In the 4th experiment, stimuli were combinations of geometric shapes and non-geometric words. The authors predicted that it would take longer to respond in incongruent conditions (e.g., the word "square" combined with the shape of a circle) than in congruent conditions. The authors found the strongest incongruency effects for the dominant hemisphere--that is, the left hemisphere for responding to words and the right hemisphere for responding to shapes. A Shape Interfering Properties hypothesis (SIP) is a possible explanation for these results.