title: Non-uniform transformation of subjective time during action preparation.
abstract: Although many studies have reported a distortion of subjective (internal) time during preparation and execution of actions, it is highly controversial whether actions cause a dilation or compression of time. In the present study, we tested a hypothesis that the previous controversy (dilation vs. compression) partly resulted from a mixture of two types of sensory inputs on which a time length was estimated; some studies asked subjects to measure the time of presentation for a single continuous stimulus (stimulus period, e.g. the duration of a long-lasting visual stimulus on a monitor) while others required estimation of a period without continuous stimulations (no-stimulus period, e.g. an inter-stimulus interval between two flashes). Results of our five experiments supported this hypothesis, showing that action preparation induced a dilation of a stimulus period, whereas a no-stimulus period was not subject to this dilation and sometimes can be compressed by action preparation. Those results provided a new insight into a previous view assuming a uniform dilation or compression of subjective time by actions. Our findings about the distinction between stimulus and no-stimulus periods also might contribute to a resolution of mixed results (action-induced dilation vs. compression) in a previous literature.
authors.affiliation: Department of Psychology, Graduate School of Humanities, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Iwasaki
authors.affiliation: Department of Psychology, Graduate School of Humanities, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
authors.forename: Kodai
authors.initials: K
authors.lastname: Tomita
authors.affiliation: Department of Psychology, Graduate School of Humanities, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan. Electronic address: ynoguchi@lit.kobe-u.ac.jp.
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Noguchi
mesh_terms: D006801:Humans; D009043:Motor Activity; D011594:Psychometrics; D011597:Psychomotor Performance; D013997:Time Factors; D013998:Time Perception
keywords: Gap detection; Internal clock; Motor commands; Time representation