Prior work has shown that humans conceptualize time in a linear fashion, a fact also evident in common phrases such as “arrow of time” and “looking forward to the future.” Here we present two complementary approaches to studying how this representation develops and how it can be accessed.
In a developmental study, we investigated the conceptualization of time by asking preschoolers through adults to locate different temporal events (e.g., morning, afternoon, evening) visually. By the age of eight, participants reliably represented events along a line suggesting that humans perceive time as a line along the horizontal axis from past to future.
Using a cognitive task, we investigated how attention interacts with an internal temporal representation. Participants were shown a series of images in three clusters followed by a temporal cue (early, middle or late) and asked to direct their attention to the corresponding cluster. We found that participants responded faster when a subsequent test probe was from the attended vs. the unattended cluster. This is analogous to the results obtained when attention is selectively deployed to a region in space.
We found converging evidence for an internal representation of time using a developmental and a cognitive framework. These results also allude to similarities between how the brain accesses space and time. In addition to contributions to our understanding of cognitive architecture, this work could potentially help us understand the link between spatial and temporal deficits in various neurological ailments.