The nature-nurture debate regarding the origin of mental lines is fundamental for cognitive neuroscience. We examined natural-nurture effects on the mental time line, applying three different challenges to the directionality of time representation. We tested (1) patients with left-neglect and healthy participants, who are (2) left-to-right or right-to-left readers/writers, using (3) a lateralized left-right button press or a vocal mode in response to a mental time task, which asks participants to judge whether events have already happened in the past or are still to happen in the future. Using lateralized responses, a spatial-temporal association of response code (STEARC) effect was found, in concordance with the cultural effects. With vocal responses (no lateralization), past and future events showed similar results in both cultures. In patients with neglect, who have a deficit of spatial attention in processing the left side of space, future events were processed more slowly and less accurately than past events in both cultures. Our results indicate the existence of a “natural” disposition to map past and future events along a horizontal mental time line, which is affected by the different ways in which spatial representation of time is introduced.
Bibliographical noteFunding Information:
The authors gratefully acknowledge Prof. Anna M. Borghi and two anonymous reviewers for their helpful comments on a previous version of this article. This work was supported by RFO (Ricerca Fondamentale Orientata, Ministry of University and Research), by a grant from Ministero della Salute (Ricerca Finalizzata PE Estero Theory-enhancing, Grant no. PE-2016-02362477, URL Ministero della Salute: http://www.salute.gov.it/portale/ministro/p4_10_1_1_ atti_1_1.jsp?lingua=italiano&id=135), and by the Israeli Science Foundation (ISF, Grant no. 315/16)) and the Agnes Ginges center of Neurogenetics - Orion Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
© 2018, The Author(s).