Matching Items (4)
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- All Subjects: Memory
- Creators: Goldinger, Stephen
- Member of: Theses and Dissertations
Description
Chronic restraint stress impairs hippocampal-mediated spatial learning and memory, which improves following a post-stress recovery period. Here, we investigated whether brain derived neurotrophic factor (BDNF), a protein important for hippocampal function, would alter the recovery from chronic stress-induced spatial memory deficits. Adult male Sprague-Dawley rats were infused into the hippocampus with adeno- associated viral vectors containing the coding sequence for short interfering (si)RNA directed against BDNF or a scrambled sequence (Scr), with both containing the coding information for green fluorescent protein to aid in anatomical localization. Rats were then chronically restrained (wire mesh, 6h/d/21d) and assessed for spatial learning and memory using a radial arm water maze (RAWM) either immediately after stressor cessation (Str-Imm) or following a 21-day post-stress recovery period (Str-Rec). All groups learned the RAWM task similarly, but differed on the memory retention trial. Rats in the Str-Imm group, regardless of viral vector contents, committed more errors in the spatial reference memory domain than did non-stressed controls. Importantly, the typical improvement in spatial memory following recovery from chronic stress was blocked with the siRNA against BDNF, as Str-Rec-siRNA performed worse on the RAWM compared to the non-stressed controls or Str-Rec-Scr. These effects were specific for the reference memory domain as repeated entry errors that reflect spatial working memory were unaffected by stress condition or viral vector contents. These results demonstrate that hippocampal BDNF is necessary for the recovery from stress-induced hippocampal dependent spatial memory deficits in the reference memory domain.
ContributorsOrtiz, J. Bryce (Author) / Conrad, Cheryl D. (Thesis advisor) / Olive, M. Foster (Committee member) / Taylor, Sara (Committee member) / Bimonte-Nelson, Heather A. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Recognition memory was investigated for naturalistic dynamic scenes. Although visual recognition for static objects and scenes has been investigated previously and found to be extremely robust in terms of fidelity and retention, visual recognition for dynamic scenes has received much less attention. In four experiments, participants view a number of clips from novel films and are then tasked to complete a recognition test containing frames from the previously viewed films and difficult foil frames. Recognition performance is good when foils are taken from other parts of the same film (Experiment 1), but degrades greatly when foils are taken from unseen gaps from within the viewed footage (Experiments 3 and 4). Removing all non-target frames had a serious effect on recognition performance (Experiment 2). Across all experiments, presenting the films as a random series of clips seemed to have no effect on recognition performance. Patterns of accuracy and response latency in Experiments 3 and 4 appear to be a result of a serial-search process. It is concluded that visual representations of dynamic scenes may be stored as units of events, and participant's old
ew judgments of individual frames were better characterized by a cued-recall paradigm than traditional recognition judgments.
ew judgments of individual frames were better characterized by a cued-recall paradigm than traditional recognition judgments.
ContributorsFerguson, Ryan (Author) / Homa, Donald (Thesis advisor) / Goldinger, Stephen (Committee member) / Glenberg, Arthur (Committee member) / Brewer, Gene (Committee member) / Arizona State University (Publisher)
Created2014
Description
An emerging literature on the relation between memory and importance has shown that people are able to selectively remember information that is more, relative to less important. Researchers in this field have operationalized importance by assigning value to the different information that participants are asked to study and remember. In the present investigation I developed two experiments, using a slightly altered value-directed-remembering (VDR) paradigm, to investigate whether and how value modifies the dynamics of memory organization and search. Moreover, I asked participants to perform a surprise final free recall task in order to examine the effects of value in the recall dynamics of final free recall. In Experiment 1, I compared the recall dynamics of delayed and final free recall between a control and a value condition, in the latter of which numbers appeared next to words, in random order, denoting the value of remembering each word during recall. In Experiment 2, I manipulated the order of presentation of the values by adding an ascending and a descending condition where values were presented in either an ascending or a descending order, respectively. Overall, my results indicated that value affected several measures of delayed and final free recall, without, in most cases, taking away the serial position effects on those same measures.
ContributorsStefanidi, Aikaterini (Author) / Brewer, Gene A. (Thesis advisor) / Glenberg, Arthur (Committee member) / Goldinger, Stephen (Committee member) / Arizona State University (Publisher)
Created2015
Description
In this study, the oppositional processes theory was proposed to suggest that reliance on semantic and episodic memory systems hinder originality during idea generation for divergent thinking tasks that are generally used to assess creative potential. In order to investigate the proposed oppositional processes theory, three experiments that manipulated the memory accessibility in participants during the alternative uses tasks were conducted. Experiment 1 directly instructed participants to either generate usages based on memory or not from memory; Experiment 2 provided participants with object cues that were either very common or very rare in daily life (i.e., bottle vs. canteen); Experiment 3 replicated the same manipulation from Experiment 2 with much longer generation time (10 minutes in Experiment 2 vs. 30 minutes in Experiment 3). The oppositional processes theory predicted that participants who had less access to direct and unaltered usages (i.e., told to not use memory, were given rare cues, or were outputting items later in the generation period) during the task would be more creative. Results generally supported the predictions in Experiments 1 and 2 where participants from conditions which limited their access to memory generated more novel usages that were considered more creative by independent coders. Such effects were less prominent in Experiment 3 with extended generation time but the trends remained the same.
ContributorsXu, Dongchen (Author) / Brewer, Gene (Thesis advisor) / Glenberg, Arthur (Committee member) / Homa, Donald (Committee member) / Goldinger, Stephen (Committee member) / Arizona State University (Publisher)
Created2017