Age Differences In Emotional Effects On Time-based Prospective Memory

Prospective memory(PM)is defined as the ability to perform activities or events in the future.Time-based prospective memory(TBPM),as one kind of PM,refers to remembering to execute an intention at a specific point or in a delayed time.Successful execution on time monitoring and intentional activities is crucial for an individual to perform a TBPM task for there is no evident target cue to reminder related task.Good TBPM is closely related to people's daily life and may be especially critical for an individual to maintain independence and autonomy in everyday life.Therefore,present study investigated which factors would influence the performance on a TBPM taks.Results indicated internal factors(e.g.personality trait,individual emotional state et al.)as well as external factors(e.g.task difficulty,experimental scene et al.)affected performance of TBPM.Due to the important role time monitoring played in TBPM task,different subjects exhibited distinctiveness on time monitoring.Compared with young adults,older adults exhibited different duration estimation when they are exposed to the same emotional valence due to mental health status,economic status and physical status and so on.Previous studies demonstrated there was a age difference on emotion affecting duration estimation.That is,in the condition of being in positive emotional status,older adults perceived longer duration length and perceived shorter duration length in negative emotional status,young people are the opposite.Hence,we hypothesis emotional valence has an impact on TBPM performance by influencing prospective duration estimation component of TBPM.Previous researches mainly investigated the negative emotional valence influencing TBPM,but relatively little is known about the influence of positive emotional valence and several related conclusions are inconsistent take all above into consideration,the aim of our present research was to investigate how different emotional valence(positive,neutral and negative)affects TBPM performance across different age group and if duration estimation does function in the process of executing TBPM task,then how the relationship would be between it and TBPM.Study 1 focused on investigating how emotional valence and age factors affected theperformance of TBPM.Sixty undergraduate students and sixty three older adults participated in this study and each age group was randomly divided into three emotion-induced subgroup,including positive,neutral and negative emotion.Video clips and story recall were presented to subjects to induce specific emotion and then subjects were required to execute TBPM task with double task paradigm.All collected data were analyzed in Statistic Package for Social Science(SPSS).Study 2 aimed to explore the role interval timing perception played in the process of emotion valence influencing TBPM performance.Sixty undergraduate students and sixty three older adults participated in this study and each age group was randomly divided into three emotion-induced subgroup,including happy,neutral and sad emotion.Video clips and story recall were presented to subjects to induce specific emotion and then subjects were required to execute interval timing perception task with bisection procedure paradigm.To maintain a persistent and same emotional status,video clips and story recall were presented to subjects again after competing time perception task and then subjects were required to perform TBPM task.We draw following conclusions from our experiments:1.Emotional valence had different effects on TBPM performance across different age groups.Sad emotion status reduced accuracy rate of TBPM task in young adults but had no effect on older adults.2.Older adults showed higher accuracy rate of TBPM in negative emotion status than positive emotion status while young adults showed higher accuracy rate of TBPM in positive emotion status than negative emotion status.3.A discussion of the role of time-span perception found that,older adults showed a tendency to underestimate duration length in negative emotion status and overestimate duration length in positive emotion status,explain that emotions affect the length of time estimates.4.The correlation analysis founded that point of subjective equality,a parameter of time estimation,showed positive correlation with accuracy rate of TBPM,shows that the greater the subjective equal point under the same emotional valence,the shorter the time-span perception,and the higher the accuracy rate of TBPM.