Distinctive features of experiential time: Duration, speed and event density.

William James's use of "time in passing" and "stream of thoughts" may be two sides of the same coin that emerge from the brain segmenting the continuous flow of information into discrete events. Herein, we investigated how the density of events affects two temporal experiences: the felt duration and speed of time. Using a temporal bisection task, participants classified seconds-long videos of naturalistic scenes as short or long (duration), or slow or fast (passage of time). Videos contained a varying number and type of events. We found that a large number of events lengthened subjective duration and accelerated the felt passage of time. Surprisingly, participants were also faster at estimating their felt passage of time compared to duration. The perception of duration scaled with duration and event density, whereas the felt passage of time scaled with the rate of change. Altogether, our results suggest that distinct mechanisms underlie these two experiential times.

Transport makes cities: transit maps as major cognitive frames of metropolitan areas.

Spatial representations play a fundamental role in navigation, decision-making, and overall interaction with our environments. Understanding how individuals construct and use them holds significant importance in spatial cognition research, and even bears practical implications for urban planning as it can explain how we interact with the spaces we inhabit. In large urban areas, transit maps stand as prominent visual aids, guiding people through public transportation systems. These maps, while designed for navigational purposes, may influence how individuals perceive and represent their cities. For instance, Vertesi (Social Studies of Science 38:09-35, 2008) showed through a series of interviews including a "sketch mapping" phase, that London Tube Map seems to structure residents' spatial representation of their city. However, thorough quantitative research on this subject have not been carried out yet. Two experimental studies have been conducted to demonstrate how residents' representations of metropolitan areas closely resemble the schematic representations of their public transport networks. First, we show that residents of Greater Paris-public and private transport users alike-plot city landmarks in a layout more closely resembling that of the Parisian transit map than the geographical map. Next, we asked Greater Berlin, London and Paris residents to place landmarks of their cities on different map backgrounds. A similar procedure was followed for landmarks from an unknown city, after a dedicated learning phase. For known cities, the sketch maps produced were closer to transit maps than to the geographical ones, although less so if the test map background presented topographical elements (e.g., rivers, etc.). For learnt cities, participants' sketch maps were almost exclusively dependent on the map provided during the learning phase. These results suggest that familiarity with transit maps has a direct impact on the metric properties of spatial representation in memory, a phenomenon we propose to call the 'schema effect'.

"Walk this way": specific contributions of active walking to the encoding of metric properties during spatial learning.

The effect of body-based information on spatial memory has been traditionally described as a facilitating factor for large-scale spatial learning in the field of active learning research (Chrastil & Warren, Psychonomic Bulletin and Review, 19(1):1-23; 2012). The specific contribution of body-based information to spatial representation properties is however not yet well defined and the mechanisms through which body-based information contributes to spatial learning are not clear enough. To disambiguate the effect of active spatial learning on the quality of spatial representations from the beneficial effect of physiological arousal, we compared four experimental conditions (walking on a unidirectional treadmill during learning, retrieval, both phases or no walking). Results showed no effect of the walking condition for a route perspective task, but a significant effect on a survey perspective task (landmark positioning on a map): participants who walked during encoding (encoding group and encoding + retrieval group) obtained better results than those who did not walk or walked only during retrieval. Geometrical analysis of spatial positions on maps revealed that the activity of walking during encoding improves the correlation between participants' coordinates and actual coordinates through better distance estimations and angular accuracy, even though the optic flow was not matched with individual walking speed. Control group variance in all measures was higher than that of the walking groups (regardless of the moment of walking). Taken together, these results provide arguments for the multimodal nature of spatial representations, where body-related information derived from walking is involved in metric properties accuracy and perspective switching.

"Run to the hills": Specific contributions of anticipated energy expenditure during active spatial learning.

Grounded views of cognition consider that space perception is shaped by the body and its potential for action. These views are substantiated by observations such as the distance-on-hill effect, described as the overestimation of visually perceived uphill distances. An interpretation of this phenomenon is that slanted distances are overestimated because of the integration of energy expenditure cues. The visual perceptual processes involved are, however, usually tackled through explicit estimation tasks in passive situations. The goal of this study was to consider instead more ecological active spatial processing. Using immersive virtual reality and an omnidirectional treadmill, we investigated the effect of anticipated implicit physical locomotion cost by comparing spatial learning for uphill and downhill routes, while maintaining actual physical cost and walking speed constant. In the first experiment, participants learnt city layouts by exploring uphill or downhill routes. They were then tested using a landmark positioning task on a map. In the second experiment, the same protocol was used with participants who wore loaded ankle weights. The results from the first experiment showed that walking uphill routes led to a global underestimation of distances compared with downhill routes. This inverted distance-of-hill effect was not observed in the second experiment, where an additional effort was applied. These results suggest that the underestimation of distances observed in Experiment 1 emerged from recalibration processes whose function was to solve the transgression of proprioceptive predictions linked with uphill energy expenditure. The results are discussed in relation to constructivist approaches on spatial representations and predictive coding theories.