The neural mechanisms underlying semantic unification and semanteme integration.

The basic composition processing of human language (at least) contains semantic unification and semanteme integration. However, previous researchers only focused on the neural mechanism underlying semantic unification. In the current study, participants were asked to complete both the semantic unification and semanteme integration tasks while undergoing functional magnetic resonance imaging (fMRI) scanning. In each task, the violated and congruent conditions were constructed. The regional activation analyses showed that the violation effect (violated > congruent) elicited more activation in the right anterior temporal lobe (RATL) in the semantic unification task and more widespread activation in the semanteme integration task. Moreover, the results of psychophysiological interaction (PPI) analyses showed that the violation effect elicited significant connectivity such as between RATL and bilateral angular gyrus (AG) only in the semanteme integration task. Altogether, these results suggested that semanteme integration elicited more activation and functional connectivity compared with semantic unification.