We investigated the role of emotion on item and source memory using the item method of directed forgetting (DF) paradigm. We predicted that emotion would produce source memory impairment because emotion would make it more difficult to distinguish between to-be-remembered (R items) and to-be-forgotten items (F items) by making memory strength of R and F items similar to each other. Participants were presented with negatively arousing, positively arousing, and neutral pictures. After each picture, they received an instruction to remember or forget the picture. At retrieval, participants were asked to recall both R and F items and indicate whether each item was an R or F item. Recall was higher for the negatively arousing than for the positively arousing or neutral pictures. Further, DF occurred for the positively arousing and neutral pictures, whereas DF was not significant for the negatively arousing pictures. More importantly, the negatively arousing pictures, particularly the ones with violent content, showed a higher tendency of producing misattribution errors than the other picture types, supporting the notion that negative emotion may produce source memory impairment, even though it is still not clear whether the impairment occurs at encoding or retrieval.

Flashbulb memories are vivid memories of the details surrounding the discovery of an emotional event. We investigated whether the nuclear accident that occurred in Japan in 1999 produced flashbulb memories among people who lived near the accident site. A questionnaire was distributed twice (approximately 3 weeks after the accident and 1 year later) to (1) the residents of the communities surrounding the accident site, (2) the students at a university near the accident site, and (3) the students at two universities far away from the accident site. Flashbulb memory holders were defined as those individuals who showed consistent memories between test and retest. The results indicated that only a small percentage of participants formed flashbulb memories. Further, no age-related decline was found. Flashbulb memories were distinguished by perfect or near perfect scores on four attributes: source, place, activity, and people. The results also indicated that the ratings on emotional reactions, personal consequentiality, and surprise did not differentiate between the flashbulb and non-flashbulb memory holders. In contrast, the flashbulb memory holders reported rehearsing more than the non-flashbulb memory holders. These results supported the notion that flashbulb memories are formed through rehearsal rather than at encoding. However, it is also possible that rehearsal was a result of the flashbulb memory.

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Previous studies that examined age differences in hypermnesia reported inconsistent results. The present experiment investigated whether the different study materials in these studies were responsible for the inconsistency. In particular, the present experiment examined whether the use of a video, as opposed to words and pictures, would eliminate previously reported age differences in hypermnesia. Fifteen college students and 15 older adults viewed a 3-minute video clip followed by two free-recall tests. The results indicated that older adults, as a whole, did not show hypermnesia. However, when older adults were divided into low and high memory groups based on test 1 performance, the high memory group showed hypermnesia whereas the low memory group did not show hypermnesia. The older adults in the low memory group were significantly older than the older adults in the high memory group - indicating that hypermnesia is inversely related to age in older adults. Reminiscence did not show an age-related difference in either the low or high memory group whereas inter-test forgetting did show an age difference in the low memory group. As expected, older adults showed greater inter-test forgetting than young adults in the low memory group. Findings from the present experiment suggest that video produces a pattern of results that is similar to the patterns obtained when words and pictures are used as study material. Thus, it appears that the nature of study material is not the source of inconsistency across the previous studies.