Spatial metaphor processing during temporal sequencing comprehension

People all over the world use spatial metaphors to represent temporal sequencing, but so far the online stages during the comprehension of temporal sequencing still lack evidence. To explore this issue, the current EEG study constructed vertical anomaly and horizontal anomaly by exchanging spatial terms in vertical and horizontal temporal sequencing concepts in Mandarin. Both the vertical and the horizontal anomaly indicated an N400 effect (340 ms after stimulus onset) and a positive effect in a late time window (620 ms after stimulus onset). Additionally, the horizontal anomaly showed a reduced P2 effect (200-260 ms after stimulus onset) that might related to spatial processing. Direct comparison between the two anomaly effects revealed that the vertical anomaly evoked a stronger effect in an early N400 time window (from 360 to 440 ms), whereas the horizontal anomaly evoked a stronger effect in a late N400 time window (from 500 to 580 ms). These results indicate multiple stages during the comprehension of temporal sequencing. The relation between the current results and spatial metaphor differences is also discussed.