The influence of chronotype on eyewitness memory performance

Abstract

People can be classified according to their chronotype, which is their preference in terms of sleeping patterns and task performance, being divided into three categories: morning-type, evening-type and neither-type. The literature suggests that the synchrony between time-of-day and chronotype could potentially result in better performance and productivity, known as the “synchrony effect”. In this study we aimed to analyse a possible interaction between chronotype (morning-type/evening-type) and time-of-day (morning/end of day) and how this interaction could influence the eyewitnesses’ memory performance. To this end, 44 participants (24 evening types and 20 morning-types) were recruited to perform two memory tasks that took place in two online sessions, at different times of the day: one in the morning and another at the end of the day. In each session, it was requested to each participant to visualise two videos, one of a crime scene and another of a neutral situation, answer questions related to the videos and complete questionnaires to collect additional variables that influence memory (e.g., stress, depression and anxiety). The order of the sessions (synchrony/asynchrony) and the presentation of the videos were counterbalanced across participants. The results indicated that the participants’ memory performance was better in the synchrony moment when compared to the asynchrony moment. It was also found that the type of chronotype did not influence the obtained results, which means that what explains the differences is just the fact that the chronotype is in synchrony or asynchrony. Finally, it was found that the influence of stress, anxiety and depression was more pronounced in neutral videos. These results could have important implications for research and interrogation practices, however further studies will be necessary to consolidate the knowledge about the influence of the chronotype and synchrony effect on eyewitness memory performance.