Dipartimento di Psicologia, Università degli Studi di Palermo, Palermo, Italy.
PLoS One. 2009 Nov 20;4(11):e7933. doi: 10.1371/journal.pone.0007933.
Recent literature documented the presence of spatial-temporal interactions in the human brain. The aim of the present study was to verify whether representation of past and future is also mapped onto spatial representations and whether the cerebellum may be a neural substrate for linking space and time in the linguistic domain. We asked whether processing of the tense of a verb is influenced by the space where response takes place and by the semantics of the verb.
Responses to past tense were facilitated in the left space while responses to future tense were facilitated in the right space. Repetitive transcranial magnetic stimulation (rTMS) of the right cerebellum selectively slowed down responses to future tense of action verbs; rTMS of both cerebellar hemispheres decreased accuracy of responses to past tense in the left space and to future tense in the right space for non-verbs, and to future tense in the right space for state verbs.
The results suggest that representation of past and future is mapped onto spatial formats and that motor action could represent the link between spatial and temporal dimensions. Right cerebellar, left motor brain networks could be part of the prospective brain, whose primary function is to use past experiences to anticipate future events. Both cerebellar hemispheres could play a role in establishing the grammatical rules for verb conjugation.
近期文献记录了人类大脑中存在时空相互作用。本研究旨在验证过去和未来的表示是否也映射到空间表示上，以及小脑是否可能是将语言领域中的空间和时间联系起来的神经基础。我们想知道动词的时态处理是否受到反应发生的空间和动词语义的影响。
过去时态的反应在左空间中得到促进，而未来时态的反应在右空间中得到促进。右小脑的重复经颅磁刺激（rTMS）选择性地减缓了动作动词的未来时态的反应速度；双侧小脑 rTMS 降低了左空间中过去时态和非动词的右空间中未来时态以及状态动词的右空间中未来时态的反应准确性。
结果表明，过去和未来的表示被映射到空间格式上，运动动作可以代表空间和时间维度之间的联系。右小脑、左运动脑网络可能是前瞻性大脑的一部分，其主要功能是利用过去的经验来预测未来的事件。两个小脑半球都可能在确定动词变位的语法规则方面发挥作用。
