The Effect Of The Ego-deletion On Time-based Prospective Memory

Corresponding to retrospective memory, prospective memory refers to the ability to carry out intended action at an appropriate time in the future while being actively engaged in an unrelated ongoing activity. And Time-based Prospective Memory means individual remembers to do something in the future at a certain point of time or after a time period. Generally speaking there are two ways that individuals can internally or externally control time-based prospective memory task requirement. Since the implementation of time-based prospective memory requires adequate resources, so that when an individual is in a state of ego-depletion, the performance of time-based prospective memory will be negatively affected to some degree. However, by using different control methods, the effect of maybe different. We designed three experiments to explore the effect of ego-depletion on time-based prospective memory under conditions of internal and external control, and explore the impact mechanism of ego-depletion on time-based prospective memory.Subjects were asked to perform different Stroop task firstly, and then completed the time-based prospective memory tasks under different conditions. And “dual task” paradigm imposed by Einstein and Mc Daniel in 1996 was used to explore the time-based prospective memory. The ongoing task was word decision task, and the time-based prospective memory task was that subjects were required to press “A” key every two minutes. The study explored the effect of ego-depletion on time-based prospective memory through three experiments. Experiment one explored the impact of ego-depletion on time-based prospective memory under internal control. In the second experiment we explored the impact of ego-depletion on time-based prospective memory when individuals under clock monitoring which was external control method. In the third experiment we explored the impact of ego-depletion on time-based prospective memory under external control of reminder.Our conclusions are as follows:(1) Stroop task can exhaust self-control resources, so that the individual is in a state of ego-depletion;(2) When one completes TBPM through the way of internal control, ego-depletion would have a negative impact on TBPM. And ego-depletion mainly cause greater interference for prospective component of TBPM, so that the individual can not be executed prospective intention at the right time.(3) When an individual used initiates external control such an clock monitoring, ego-depletion had no effect on the time-based prospective memory. The use of clock monitor depended on different groups — high ego-depletion groups presented the trajectory of “accelerate the increase after the first decrease”, while the low ego-depletion group showed “speed increase” pattern.The performance of TBPM has close relationship with clock monitoring. Only near the target time(period 4) the frequency of clock monitoring and TBPM performance had positive correlation, and the total number of clock monitoring and TBPM score also had a significant positive correlation.(4)When using the external control such as reminder, the effect of ego-depletion on time-based prospective memory may vary due to different reminders. When the reminder were time and the keypad, ego-depletion had a negative impact TBPM score. But ego-depletion has no effect on TBPM score under a simple keypad reminder.