Semantic processing in the left versus right cerebral hemispheres following unilateral hand contractions

ABSTRACT

Unilateral hand contractions increase activation in the motor cortex of the contralateral hemisphere, providing a means to alter the relative degree of activation in the right hemisphere versus the left hemisphere through spreading activation. Prior research reported enhanced verbal creativity as measured by performance on remote associate problems in Hebrew from left-hand contractions (right-hemisphere activation). We sought to extend the previous findings to English problems and to homograph interpretation. In Experiment 1, unilateral hand contractions in fact altered performance on the English remote associates, but in the direction of improved performance following right-hand contractions and left-hemisphere activation. In Experiment 2, the probability of retrieving atypical interpretations of homographs with multiple meanings was least likely for left-hemisphere dominant strong right handers, but the hand contraction manipulation had no effect.

KEYWORDS:

• Unilateral hand contractions
• hemispheric differences
• coarse semantic coding
• line bisection
• creativity

Acknowledgement

The authors thank Andrew Mertens, Matthew Jedlinski, Kathryn Smith, and Rukmini Roy for their help with data collection and coding.

Disclosure statement

No potential conflict of interest was reported by the authors.