Abstract:

It has been demonstrated that the spatial representation of time is psychologically real, and the experience responsible for the formation of the "Time is Space" conceptual metaphor is associated with reading/writing directionality. Perceptual symbol theory assures that the spatial mapping of time derived from reading/writing is perceptual. That is to say, the temporal-spatial metaphor is grounded on modality- specific systems. Previous studies have shown that facilitation for the association of past with left and future with right was found only in the visual and motor modality, while none in the auditory modality. The difference of time metaphor between the visual and motor modality remains largely unexplored. In this study, three experiments were conducted to compare the spatial mapping of time between the visual and motor modality. In each experiment, a spatial Stroop task was carried out. Time series, which were displayed on the middle of the screen, were used as clues. Arrows, as targets, were displayed on the left, right, top or bottom of the screen, pointing to four directions. Arrow location and pointing direction were completely orthogonal to temporal reference. The participants were asked to indicate the direction to which the arrow pointed. Experiment 1 used a square as clues to explore whether the horizontal and vertical facilitation effects were modality-specific. The results proved that the horizontal and vertical facilitation effects existed in the visual and motor modality. Experiment 2 explored the difference of horizontal time metaphor between the visual and motor modality by Mandarin Speakers. A 2×2×2 repeated measure design was adopted with independent variables of temporal reference (before/after), target location (left /right) and response side (left / right).The results showed horizontal metaphoric representation of time was observed both at the visual and motor level of Mandarin Speakers. Processing time series affected the orienting of visual attention and the activation of motor responses. Participants were faster both to identify targets and to respond to the left when the cue was a word in a forward position of time series, and the opposite was true when the cue was a word in a afterward position of time series. Experiment 3 adopted the same task as Experiment 2, except changing target location and response side into top/ bottom. Experiment 3 observed the same facilitation effect in the visual modality as Experiment 2. But facilitation effect in the motor modality was not complete. Participants were faster to respond to the top only when the cue was a word in a forward position of time series. Processing words in a forward position of time series could not accelerate the response to the bottom. Experiment 4 increased the number of target location and response side. A 2×4×4 repeated measure design was adopted with independent variables of temporal reference (before/after), target location (left /right/top/bottom) and response side (left /right/top/bottom). Results showed facilitation effect of vertical direction in the motor modality which was not complete in Experiment 3 totally disappeared. It indicated that vertical metaphoric representation of time in the visual modality was stronger than the one in the motor modality. The explanation could be that Mandarin speakers' former top-down reading/writing directionality has been changed into "from left to right". The vertical sensori-motor experience from the visual and motor modality were unequal, which led to the incomplete time metaphor in the motor modality. In a word, Spatial information activated when processing time series was perceptual, which was different from the one activated by the spatial clue. In different modalities, time metaphor was different.

Key words: time metaphor, perceptual symbol systems, propositional symbol system, temporal-spatial congruency effects