Thesis (Ph. D.)--Carleton University, 2000. / Also available in electronic format on the Internet.

The experiments studied the ability to perceive visual, events of a very simple kind: the appearance and disappearance of isolated dots in random dot patterns. The aim of the investigation was to explore the limits of this ability and clarify the relationship, between event perception and sensory storage. The first series of experiments studied the ability to detect the appearance and disappearance of single dots. Under appropriate conditions such changes can be detected in a pattern containing 1024 dots with 98% accuracy. This level of accuracy was largely maintained over manipulation of the number of dots in the pattern, pattern size and separation between dots. Performance was unaffected by whether pattern luminance was uniform or not. It is argued that to explain this performance the notion of sensory integration must be augmented by the concept of sensory differentiation. The ability to detect events was further investigated as a function of pattern complexity and ISI. The storage underlying event detection has a very high capacity and a short duration. The second series of experiments investigated the ability to perceive patterns of events. Letters defined by either appearances or disappearances were accurately identified; thus a pattern which was not visible was made visible by its disappearance. A measure of localization was obtained by requiring subjects to judge whether three events were aligned. It is concluded that both onset and offset of a pattern convey information about form but that acuity for events is poorer than for sustained stimuli. The possibility that event perception is achieved by integration at short stimulus durations was investigated by varying the durations of the patterns before and after the events. Little evidence for event perception by integration was found; increasing the durations of the patterns either improved performance or had little or no effect on it. The final experiment examined a conflict between the present results and studies of visual integration. The ability to perceive mixtures of appearances and disappearances was investigated and found to be poorer than the ability to process either type of event alone. The ability to detect and locate events is highly developed. This ability seems well adapted to the detection and perception of significant change in the natural environment. In contrast to the increasing scepticism concerning the function of sensory storage it is concluded that event perception is an important visual function in which sensory storage is clearly implicated.

Research in our laboratory has demonstrated blocked and recovered memories within the context of a controlled experiment. The comparative memory paradigm allows for comparisons of recovered memories, continuous memories, and false memories. Additional research in our laboratory has shown two distinct types of memory errors; semantic based errors which occur due to pre-existing category knowledge, and episodic based errors in which the source of details (list members) are misattributed. Independently, these two lines of research have illuminated basic memory processes, however, they have not been combined previously. That is, the experiments in the present study explore the susceptibility of recovered memories to semantic and episodic based errors relative to continuous memories. Experiment 1 replicated the large blocking and recovery effects previously found by our laboratory. Additionally, it demonstrated that recovered memories were no more prone to semantic based errors than were continuous memories. These errors occurred very infrequently despite the use of materials chosen specifically to induce such errors. Experiment 2 again replicated the large blocking and recovery effects. The equivalent low rate of semantic based errors was also replicated. However, Experiment 2 also revealed that recovered memories were more susceptible to episodic based errors than were continuous memories. This was especially true when the memory block occurred in an interference treatment condition. Finally, post-recall source recognition tests failed to improve memory accuracy. In fact, numerically both semantic based and episodic based errors increased on the source recognition test relative to the cued recall test. Findings are discussed in relation to the source monitoring and fuzzy-trace theories of memory as well as the legal and clinical recovered memory controversy.

Research in our laboratory has demonstrated blocked and recovered memories within the context of a controlled experiment. The comparative memory paradigm allows for comparisons of recovered memories, continuous memories, and false memories. Additional research in our laboratory has shown two distinct types of memory errors; semantic based errors which occur due to pre-existing category knowledge, and episodic based errors in which the source of details (list members) are misattributed. Independently, these two lines of research have illuminated basic memory processes, however, they have not been combined previously. That is, the experiments in the present study explore the susceptibility of recovered memories to semantic and episodic based errors relative to continuous memories. Experiment 1 replicated the large blocking and recovery effects previously found by our laboratory. Additionally, it demonstrated that recovered memories were no more prone to semantic based errors than were continuous memories. These errors occurred very infrequently despite the use of materials chosen specifically to induce such errors. Experiment 2 again replicated the large blocking and recovery effects. The equivalent low rate of semantic based errors was also replicated. However, Experiment 2 also revealed that recovered memories were more susceptible to episodic based errors than were continuous memories. This was especially true when the memory block occurred in an interference treatment condition. Finally, post-recall source recognition tests failed to improve memory accuracy. In fact, numerically both semantic based and episodic based errors increased on the source recognition test relative to the cued recall test. Findings are discussed in relation to the source monitoring and fuzzy-trace theories of memory as well as the legal and clinical recovered memory controversy.

The false/ recovered memory debate has highlighted the complexities involved in assessing the validity of memories for emotional childhood events. This dissertation begins by tracing the history of the dominant school of thought on memory, the spatial perspective, as well as far less conspicuous reconstructive views, and challenges influential modern spatial views (e.g., repression) in light of a more defensible reconstructive model. The empirical component of this dissertation was designed to compare the nature of real, created, and fabricated childhood memories for emotional events within individuals. The critical issues being addressed in the experiment were: (1) whether people could come to remember false ("created") memories for emotional events; (2) if so, whether differences existed between created memories and real and/or intentionally lied about (fabricated) memories, and; (3) whether there were individual differences in susceptibility to created memories. Using a variation of an approach developed by Hyman, Husband, and Billings (1995), a questionnaire was forwarded to participants' parents inquiring about six categories of negative emotional events (serious medical procedure, serious animal attack, getting seriously hurt by another child, serious indoor accident, serious outdoor accident, and getting lost) which the participant may or may not have experienced between the ages of 4 and 10 years. Parents were asked to describe each event which had occurred and to give a number of specific pieces of information relating to the event. Based on the questionnaire information (85% response rate), 77 participants were interviewed about each of a: (1) real event; (2) false event; and (3) fabricated event, in three weekly-spaced interviews. Over the three interviews, the interviewers attempted to implant a created memory for the false emotional event using encouragement, context reinstatement, guided imagery, and instructing daily recall attempts. In the first interview, participant were asked about the real event and the false event (counterbalanced), each introduced as a true event. They were provided the event tide and four specific pieces of information to cue their memories (their age, location, season/ month, and people present), based on questionnaire information (contrived for the false events). In the second interview, participants were re-interviewed about their memories for the false event followed by the implantation procedure. In the third interview, participants were again interviewed about the false event with the same interview approach. Finally (after the last attempt at recalling the false event), they were provided written instructions to fabricate a childhood memory, again with an event category and four information clues, given preparation rime and a monetary incentive, and interviewed about the fabricated event with the same format as the other two memory types. Following transcription of the two or three (if a created memory had emerged) final memory reports, the memories were compared on several dependent measures, collectively designated the Memory Assessment Procedure (MAP), relating to their subjective and presentation characteristics. Participants were then asked to complete a Dissociative Experiences Scale (DES) questionnaire to examine if susceptibility to created memories was related to a general dissociative cognitive pattern. Results indicated that twenty (26%) of participants created complete memories for the false emotional events (seven animal attacks, five instances of getting seriously hurt by another child, four serious outdoor accidents, three episodes of getting lost, and one medical procedure). Furthermore, 29.9% of participants reported some false information pertaining to the false event ("partial" memories), for a total of 55.9% of participants recalling information relating to the false event. The remaining participants (44.2%) reported no information pertaining to the false event. There were several interesting differences among the three memory types, including stress ratings, vividness/ clarity ratings, confidence ratings, coherence, number of details, repeated details, and memory failures. For example, when relating a created memory, participants were less confident and the memories were less vivid and detailed compared to the other memory types, but similar in sensory components and relevancy. On the other hand, participants were highly confident in their fabricated memories which were rated as highly stressful and vivid, and the memories were detailed. However, when relating a fabricated memory, participants repeated details and were less willing to admit lacking memory, relative to real memories. Other findings are reported on the origin of the created memories, age factors, memory perspective, reasons provided for first forgetting the false event, and post-interview confidence in the created memories. On the DES , participants who had come up with a partial or a created memory scored, on average, about twice as high as those participants who had recalled no false information, indicating that susceptibility to memory distortion may be related to a general dissociative pattern. This was the largest scale created memory study to date and the first to look at a variety of emotional childhood events and the content of the memories. Implications of the findings for the false memory debate and memory assessment in forensic contexts are discussed.

Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 68-80) Also available in print.

The false/ recovered memory debate has highlighted the complexities involved in assessing the validity of memories for emotional childhood events. This dissertation begins by tracing the history of the dominant school of thought on memory, the spatial perspective, as well as far less conspicuous reconstructive views, and challenges influential modern spatial views (e.g., repression) in light of a more defensible reconstructive model. The empirical component of this dissertation was designed to compare the nature of real, created, and fabricated childhood memories for emotional events within individuals. The critical issues being addressed in the experiment were: (1) whether people could come to remember false ("created") memories for emotional events; (2) if so, whether differences existed between created memories and real and/or intentionally lied about (fabricated) memories, and; (3) whether there were individual differences in susceptibility to created memories. Using a variation of an approach developed by Hyman, Husband, and Billings (1995), a questionnaire was forwarded to participants' parents inquiring about six categories of negative emotional events (serious medical procedure, serious animal attack, getting seriously hurt by another child, serious indoor accident, serious outdoor accident, and getting lost) which the participant may or may not have experienced between the ages of 4 and 10 years. Parents were asked to describe each event which had occurred and to give a number of specific pieces of information relating to the event. Based on the questionnaire information (85% response rate), 77 participants were interviewed about each of a: (1) real event; (2) false event; and (3) fabricated event, in three weekly-spaced interviews. Over the three interviews, the interviewers attempted to implant a created memory for the false emotional event using encouragement, context reinstatement, guided imagery, and instructing daily recall attempts. In the first interview, participant were asked about the real event and the false event (counterbalanced), each introduced as a true event. They were provided the event tide and four specific pieces of information to cue their memories (their age, location, season/ month, and people present), based on questionnaire information (contrived for the false events). In the second interview, participants were re-interviewed about their memories for the false event followed by the implantation procedure. In the third interview, participants were again interviewed about the false event with the same interview approach. Finally (after the last attempt at recalling the false event), they were provided written instructions to fabricate a childhood memory, again with an event category and four information clues, given preparation rime and a monetary incentive, and interviewed about the fabricated event with the same format as the other two memory types. Following transcription of the two or three (if a created memory had emerged) final memory reports, the memories were compared on several dependent measures, collectively designated the Memory Assessment Procedure (MAP), relating to their subjective and presentation characteristics. Participants were then asked to complete a Dissociative Experiences Scale (DES) questionnaire to examine if susceptibility to created memories was related to a general dissociative cognitive pattern. Results indicated that twenty (26%) of participants created complete memories for the false emotional events (seven animal attacks, five instances of getting seriously hurt by another child, four serious outdoor accidents, three episodes of getting lost, and one medical procedure). Furthermore, 29.9% of participants reported some false information pertaining to the false event ("partial" memories), for a total of 55.9% of participants recalling information relating to the false event. The remaining participants (44.2%) reported no information pertaining to the false event. There were several interesting differences among the three memory types, including stress ratings, vividness/ clarity ratings, confidence ratings, coherence, number of details, repeated details, and memory failures. For example, when relating a created memory, participants were less confident and the memories were less vivid and detailed compared to the other memory types, but similar in sensory components and relevancy. On the other hand, participants were highly confident in their fabricated memories which were rated as highly stressful and vivid, and the memories were detailed. However, when relating a fabricated memory, participants repeated details and were less willing to admit lacking memory, relative to real memories. Other findings are reported on the origin of the created memories, age factors, memory perspective, reasons provided for first forgetting the false event, and post-interview confidence in the created memories. On the DES , participants who had come up with a partial or a created memory scored, on average, about twice as high as those participants who had recalled no false information, indicating that susceptibility to memory distortion may be related to a general dissociative pattern. This was the largest scale created memory study to date and the first to look at a variety of emotional childhood events and the content of the memories. Implications of the findings for the false memory debate and memory assessment in forensic contexts are discussed. / Arts, Faculty of / Psychology, Department of / Graduate

published_or_final_version / Psychology / Master / Master of Philosophy

Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 205-213). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 100-103).