Carrying groceries: More items in early trips than in later trips or the reverse? Implications for pre-crastination

Time perspectives and precrastination: Understanding early task completion in a time-moving perspective

This study examines the relationship between precrastination-a tendency to complete tasks early-and the time-moving perspective. Given the opposing nature of precrastination and procrastination, we hypothesize that precrastination correlates positively with a time-moving perspective, based on the finding that procrastination correlates with an ego-moving tendency. To test this, we conducted a survey with 366 participants (172 females aged 17 to 68), assessing their tendencies toward precrastination and their responses to the classic "ambiguous meeting question" (McGlone & Harding, 1998). Participants who selected "Monday" as the answer to the ambiguous time-related question displayed higher precrastination scores than those who chose "Friday," supporting the hypothesis. To address the potential subjectivity of self-reported data, we included an objective measurement by recording participants' arrival times for a scheduled test in a controlled setting involving 84 students (42 females aged 18 to 25). The results showed that participants who arrived early were more likely to choose "Monday" in a modified version of the "ambiguous meeting question," further validating our hypothesis. This study highlights the significant role of precrastination in shaping time perception.

Pre-crastination across physical and cognitive tasks

Pre-crastination refers to the tendency to begin a task as soon as possible, even at the cost of additional effort. This phenomenon is consistently observed in tasks in which participants are asked to select one of two buckets to carry to a target. Surprisingly, on a high proportion of trials participants choose the bucket that is closer to them (and further from the target) as opposed to the bucket that is further from them (and closer to the target). In other words, participants tend to complete the task of picking up a bucket as soon as possible, even when this requires additional physical effort. The purpose of the current experiment was to test whether an individual's tendency to pre-crastinate is stable across tasks. Participants performed a physical load task where they selected one of two buckets to carry to a target. The same participants performed a cognitive load task where they picked up number strings at one of the two bucket locations and mentally carried the number string to a target. We found that participants pre-crastinated in both tasks and this tendency was reduced as task difficulty increased. Importantly, we found a significant association between an individual's tendency to pre-crastinate in the physical load task and their tendency to pre-crastinate in the cognitive load task. Thus, an individual's tendency to pre-crastinate is consistent across tasks and suggests that this is a stable characteristic of how individuals choose to order tasks.

Physical effort precrastination determines preference in an isometric task

How the brain decides when to invest effort is a central question in neuroscience. When asked to walk a mile to a destination, would you choose a path with a hill at the beginning or the end? The traditional view of effort suggests we should be indifferent-all joules are equal so long as it does not interfere with accomplishing the goal. Yet, when total joules are equal across movement decisions, the brain's sensitivity to the temporal profile of effort investment remains poorly understood. Here, we sought to parse the interaction of time and physical effort by comparing subjective preferences in an isometric arm-pushing task that varied the duration and timing of high and low effort. Subjects were presented with a series of two-alternative forced choices, where they chose the force profile they would rather complete. Subjects preferred earlier physical effort (i.e., to precrastinate) but were idiosyncratic about preference for task timing. A model of subjective utility that includes physical effort costs, task costs, and independent temporal sensitivity factors described subject preferences best. Interestingly, deliberation time and response vigor covary with the same subjective utility model for preference, suggesting a utility that underlies both decision making and motor control. These results suggest physical effort costs are temporally sensitive, with earlier investment of effort preferred to later investment, and that the representation of effort is based on not only the total energy required but also when it is required to invest that energy.NEW & NOTEWORTHY We use a novel paradigm that differentiates physical effort costs, task costs, and time, where subjects choose between isometric arm-pushing tasks. Subjects prefer high physical effort earlier than later. They also decide faster and respond more vigorously the greater their preference. We find a generalizable subjective utility model that includes independent time-sensitivity of physical effort and task costs. Together, we demonstrate that subjective effort includes not only the total effort invested but also its timing.