The temporal dynamics underlying the comprehension of scientific metaphors and poetic metaphors

The neural mechanisms underlying the processing of novel metaphors created from poetic contexts have been investigated in previous experiments. Considering the different attributes of metaphors, the current study compared the temporal dynamics for processing two kinds of novel metaphors with event-related potentials (ERPs): scientific metaphors and poetic metaphors. Amplitudes of the N400 (350-450 ms) were similar for scientific metaphors and poetic metaphors. Within the LPC window (550-850 ms), ERPs associated with these two kinds of novel metaphors were observed every 100 ms in three successive subwindows. We found that due to a sustained late negativity overlapping in time and space with the LPC scientific metaphors seemingly elicited the least positive LPC throughout. More importantly, with the passage of time, the LPC waveforms for scientific metaphors diverged from those for poetic metaphors and conventional metaphors while LPC waveforms for poetic metaphors converged with those for conventional metaphors. The reported results indicate the possible different time courses for processing novel metaphors with different contextual structures and different functions. And the findings are compatible with recent brain imaging studies and complement them by adding such new dimensions as the temporal dynamics and the properties of novel metaphors.