Abstract:

Previous research has revealed robust differences between young and older adults’ accurate emotional memory. Typically, negative emotion prompts memory performance in young adults, while positive emotion benefits memory performance in older adults. Relatively, much less efforts have been devoted to investigating how emotion divergently influences false memory in older adults compared to young adults. The main purpose of the present study is to explore, first, how age alters the effects of emotional valence on false memory; and second, what are the cognitive mechanisms for the interaction effect of age and emotional valence on false memory. The Fuzzy Trace Theory (FTT) uses verbatim memory trace and gist memory trace to interpret individuals’ false memory, especially false memory under the framework of Deese-Roediger-McDermott (DRM) paradigm. According to recent research, we proposed some flaws of traditional paradigms (such as the Remember-Know paradigm) in the area of false memory; and we also argued that it would be critical to include response bias in addition to verbatim and gist memory trace to investigate false memory. To fulfill this need, the simplified conjoint recognition (SCR) paradigm, combined with a statistical method of multinomial processing tree model, was used in the present study to investigate false memory and its associated cognitive mechanisms. A sample of 34 young adults (aged 23 ± 2 years) and 28 older adults (aged 68 ± 5 years) completed the SCR task. In the task, the Cornell/Cortland emotion word lists, along with neutral word lists adopted from previous research, were implemented as experimental materials. The results displayed a significant interaction effect of emotional valence and age on false memory (i.e. false alarm). Specifically, positive emotion decreased older adults’ false memory, while negative emotion decreased young adults’ false memory. The method of multinomial processing tree model was further employed to model, parameterize and inference the cognitive mechanisms related to the effect of emotional valence on false memory within young and older group. It was found that negative emotion contributed to a lower level of false memory in young adults by lowering their response bias toward negative words. As to older adults, positive emotion boosted retrieval of verbatim memory trace and hampered retrieval of gist memory trace, then led to less false memory for positive words. Our study uncovered interesting age-related differences in emotional false memory; it also confirmed the necessity of a simultaneous consideration of verbatim memory trace, gist memory trace and response bias when investigating false memory.

Key words: false memory, emotional valence, age-related difference, simplified conjoint recognition paradigm, multinomial processing tree model