Neural Correlates of Temporal Presentness in the Precuneus: A Cross-linguistic fMRI Study based on Speech Stimuli.

The position of any event in time could be in the present, past, or future. This temporal discrimination is vitally important in our daily conversations, but it remains elusive how the human brain distinguishes among the past, present, and future. To address this issue, we searched for neural correlates of presentness, pastness, and futurity, each of which is automatically evoked when we hear sentences such as "it is raining now," "it rained yesterday," or "it will rain tomorrow." Here, we show that sentences that evoked "presentness" activated the bilateral precuneus more strongly than those that evoked "pastness" or "futurity." Interestingly, this contrast was shared across native speakers of Japanese, English, and Chinese languages, which vary considerably in their verb tense systems. The results suggest that the precuneus serves as a key region that provides the origin (that is, the Now) of our time perception irrespective of differences in tense systems across languages.

[Development of Temporal Systems in Child Language from the Viewpoint of Universality and Variation in the Encoding of Time in Human Languages].

This study explores how time is conceptualized and linguistically encoded by human beings. In order to examine how the temporal systems develop in child language, we have conducted investigations on how their development relates to universal and idiosyncratic aspects of the temporal systems of the languages of the world. We have found that both the uniformity and the variation across languages in the development of tense-aspect marking in child language are attributable to the interaction of three aspects of the typological pattern of the target language: morphology, the presence or absence of optionality of tense-aspect marking, and the inventory of tense-aspect markers.