Highly Superior Autobiographical Memory (HSAM): Memory Distortion Paradigms and Individual Differences
- Author(s): Patihis, Lawrence
- Advisor(s): Loftus, Elizabeth F
- et al.
This dissertation addresses two basic questions: 1. Are people with highly superior autobiographical memory (HSAM) susceptible to memory distortions? 2. What is different about them that might offer clues that would help explain their ability? To answer the first question thoroughly, HSAM individuals and age match controls participated in a number of memory distortion tasks. In the DRM memory distortion word list paradigm we found that HSAM participants had comparably high rates of critical lure endorsement, indicating a vulnerability to false memories brought about by associations. They also participated in a classic misinformation experiment with photographic slides as the original event, and text narratives containing some pieces of misinformation. At the subsequent memory test HSAM individuals indicated more false memories than control participants, a finding that became non-significant when adjusting for individual differences in absorption. After a subsequent source test, HSAM and control participants had comparable numbers of false memories from misinformation.
In semi-autobiographical memory distortion tasks, HSAM and control participants had fairly similar rates overall. For example, in a nonexistent news footage task using suggestion (also known as the "crashing memory" paradigm) 10% of HSAM individuals said they had seen the footage (a further 10% indicated maybe/unsure), whilst 18% of controls did (5% maybe; ns). A guided imagery task, with the same nonexistent footage as the target event, produced similarly increased rates of false report in HSAM (17% changed from "no" to "yes") and control (10% from "no" to "yes") participants. Memory for their emotions in the week after 9/11 was similarly inconsistent in HSAM and control participants. These results suggest that, relative to controls, HSAM individuals are as susceptible to both misinformation and reappraisals when the target events are semi-autobiographical.
The second main research question asked what is different about HSAM individuals that might give us clues as to why they have their ability? To answer this we measured HSAM participants' and age/gender matched controls' on a number of behavioral measures to test three main hypotheses: imaginative absorption, emotional arousal, and sleep. HSAM participants were significantly higher than controls on two dispositions--absorption and fantasy proneness. These two dispositions were associated with a measure of HSAM ability within the superior memory participants. The emotional arousal hypothesis yielded only weak support. The sleep hypothesis was not supported in terms of quantity, but sleep quality may be a small factor worthy of further research. Other individual differences are also documented. Speculative pathways describing how absorption and fantasizing could lead to enhanced autobiographical memory are discussed.