Graduate Recital: Nicholas LaPagalia, Tenor

Kemp Recital Hall Sunday Evening April 21, 199

Testing can enhance or reduce suggestibility: The importance of contextual detail during misinformation exposure

Witnesses are likely to describe an event to a police investigator or 911 operator soon after the event and prior to any exposure to misinformation. Recent studies have found that recalling an event can increase people\u27s suggestibility (e.g., Chan, Thomas, & Bulevich, 2009) while other studies have reported that retrieval can reduce subsequent eyewitness suggestibility (e.g., Pansky & Tenenboim, 2011). In this dissertation, I examined whether differences in the way misinformation is presented can modulate the effects of testing on suggestibility. Participants watched a video of a robbery and some were questioned about the event immediately afterwards. Later, participants were exposed to misinformation in a narrative (Experiment 1a) or in questions (Experiment 1b). Consistent with previous studies, testing increased suggestibility when misinformation was presented via a narrative; however, when misinformation was presented in questions, testing decreased suggestibility. In Experiments 2 and 3, I sought to uncover why the retrieval-enhanced suggestibility (RES) effect was eliminated when misinformation was presented in questions. Experiment 2 was designed to address whether differences in the presentation duration of misinformation can account for the opposite patterns of results in Experiment 1 - they cannot. In Experiment 3, I manipulated whether a) misinformation was presented in questions or a narrative and b) the amount of contextual detail presented with the misinformation. I found that an RES effect was present only when misinformation was embedded in rich contextual details, regardless of whether misinformation was presented in questions or a narrative. Consistent with these data, previous studies that have found an RES effect have used misinformation narratives that included many additional contextual details (e.g., Chan & LaPaglia, 2011), whereas work showing a testing benefit has consistently presented misinformation in relative isolation (e.g., LaPaglia & Chan, 2012). These results suggest that the way in which misinformation is presented determines whether initial testing enhances or reduces suggestibility. The main findings are discussed within the context of discourse comprehension and narrative persuasion

Changes in preservice teacher dispositions during a teacher preparation program

Although substantial attention is being paid nationally to the assessment of pre-service teacher dispositions, largely to meet accreditation requirements, little is known about the extent to which standards-based dispositions change during a preparation program. A systematic approach to tracking change, or the lack thereof, using valid and reliable instruments of varying item types, can help faculty determine if candidates’ dispositions are positive and improving at the individual student and group levels. Pre-existing affective and cognitive data for six cases were analyzed for evidence of consistency with the 10 interstate teacher assessment and support consortium or InTASC standards. Dispositions improved as the cases progressed through their programs

Impairing Existing Declarative Memory in Humans by Disrupting Reconsolidation

During the past decade, a large body of research has shown that memory traces can become labile upon retrieval and must be restabilized. Critically, interrupting this reconsolidation process can abolish a previously stable memory. Although a large number of studies have demonstrated this reconsolidation associated amnesia in nonhuman animals, the evidence for its occurrence in humans is far less compelling, especially with regard to declarative memory. In fact, reactivating a declarative memory often makes it more robust and less susceptible to subsequent disruptions. Here we show that existing declarative memories can be selectively impaired by using a noninvasive retrieval–relearning technique. In six experiments, we show that this reconsolidation-associated amnesia can be achieved 48 h after formation of the original memory, but only if relearning occurred soon after retrieval. Furthermore, the amnesic effect persists for at least 24 h, cannot be attributed solely to source confusion and is attainable only when relearning targets specific existing memories for impairment. These results demonstrate that human declarative memory can be selectively rewritten during reconsolidation

The Dark Side of Testing Memory: Repeated Retrieval Can Enhance Eyewitness Suggestibility

Eyewitnesses typically recount their experiences many times before trial. Such repeated retrieval can enhance memory retention of the witnessed event. However, recent studies (e.g., Chan, Thomas, & Bulevich, 2009) have found that initial retrieval can exacerbate eyewitness suggestibility to later misleading information—a finding termed retrieval-enhanced suggestibility (RES). Here we examined the influence of multiple retrieval attempts on eyewitness suggestibility to subsequent misinformation. In four experiments, we systematically varied the number of initial tests taken (between zero and six), the delay between initial testing and misinformation exposure (~30 min or 1 week), and whether initial testing was manipulated between- or within-subjects. University undergraduate students were used as participants. Overall, we found that eyewitness suggestibility increased as the number of initial tests increased, but this RES effect was qualified by the delay and by whether initial testing occurred in a within- or between-subjects manner. Specifically, the within-subjects RES effect was smaller than the between-subjects RES effect, possibly because of the influence of retrieval-induced forgetting/facilitation (Chan, 2009) when initial testing was manipulated within subjects. Moreover, consistent with the testing effect literature (Roediger & Karpicke, 2006), the benefits of repeated testing on later memory were stronger after a 1-week delay than after a 30-min delay, thus reducing the negative impact of RES in long-term situations. These findings suggest that conditions that are likely to occur in criminal investigations can either increase (repeated testing) or reduce (delay) the influence of RES, thus further demonstrating the complex relationship between eyewitness memory and repeated retrieval. (PsycINFO Database Record (c) 2012 APA, all rights reserved

Telling a good story: The effects of memory retrieval and context processing on eyewitness suggestibility

Witnesses are likely to describe a crime many times before testifying or encountering misinformation about that crime. Research examining the effect of retrieval on later suggestibility has yielded mixed results. LaPaglia and Chan manipulated whether misinformation was presented in a narrative or misleading questions, and they found that retrieval increased suggestibility when misinformation was presented in a narrative, but reduced suggestibility when the same misinformation was presented in questions. In the current study, we aimed to address why these differences occurred. Specifically, we examined whether contextual detail and narrative coherence during misinformation exposure influenced the relation between retrieval and suggestibility. Participants watched a robbery video and some were questioned about the event afterwards. They were then exposed to misinformation presented in a narrative (Experiment 1) or questions (Experiment 2) before taking a final memory test. Testing enhanced suggestibility when the misinformation phase reinstated contextual information of the event, but not when the misinformation phase included few contextual details–regardless of whether the misinformation was in a narrative or questions. In Experiment 3, disrupting narrative coherence by randomizing the order of contextual information eliminated retrieval-enhanced suggestibility. Therefore, context processing during the post-event information phase influences whether retrieval enhances or reduces eyewitness suggestibility

Reverse Genetics of Influenza B and the Development of a Novel LAIV Vaccine

Due to the disease burden of influenza virus types A and B, vaccines, which are manufactured as formalin-inactivated killed virus (KV) and live-attenuated virus (LAIV), are produced to provide coverage against currently circulating influenza A (IAV) and B (IBV) viruses. Although the licensed LAIV vaccine provides enhanced coverage over the KV vaccine, it is only licensed for immunocompetent individuals ages 2-49 years without pre-existing conditions, so individuals who are most at risk cannot receive it. Previously, our lab showed that incorporation of an 8 amino acid HA tag in frame at the C-terminus of the PB1 open-reading frame (ORF) in addition to the mutations found in the PB2 and PB1 segments of the licensed LAIV vaccine yielded a stable, efficacious alternative LAIV vaccine for IAV; however, to develop a complete vaccine, a corresponding IBV candidate is required. Towards this goal, a contemporary IBV strain, B/Brisbane/60/2008, was cloned and recovered by reverse genetics (RG-B/Bris). Subsequently, it was demonstrated that the parental and RG-B/Bris show similar growth kinetics in vitro. An initial vaccine attempt, which combined PB2 cap-binding mutants with the HA tag in PB1, was made but led to the realization of the PB2 cap-binding mutations, PB2 W359F and F406Y, as virulence factors. In a subsequent vaccine attempt, mutations analogous to those found only in segment 2 of the A/Ann Arbor/6/60 cold-adapted LAIV backbone were introduced into the homologous segment of RG-B/Bris. The following mutations were introduced into the PB1 gene segment of RG-B/Bris, either in the presence or absence of a C-terminal HA tag: K391E, E580G, and S660A. Two viruses were rescued, referred to as RG-B/Bris ts and RG-B/Bris att, both containing the set of three amino acid mutations but differing in the absence or presence of the HA tag, respectively. Both viruses showed ideal attenuation, safety, and immunogenicity in DBA/2 mice and conferred protection against lethal IBV challenge. More importantly, RG-B/Bris att, but not RG-B/Bris ts, showed ideal stability with no reverting mutations over 8 passages in eggs. Taken together, a stable, immunogenic, and live attenuated virus alternative to the current live influenza B virus vaccine was produced

Interspecific trait variability and local soil conditions modulate grassland model community responses to climate

Medium‐to‐high elevation grasslands provide critical services in agriculture and ecosystem stabilization, through high biodiversity and providing food for wildlife. However, these ecosystems face elevated risks of disruption due to predicted soil and climate changes. Separating the effects of soil and climate, however, is difficult in situ, with previous experiments focusing largely on monocultures instead of natural grassland communities. We experimentally exposed model grassland communities, comprised of three species grown on either local or reference soil, to varied climatic environments along an elevational gradient in the European Alps, measuring the effects on species and community traits. Although species‐specific biomass varied across soil and climate, species' proportional contributions to community‐level biomass production remained consistent. Where species experienced low survivorship, species‐level biomass production was maintained through increased productivity of surviving individuals; however, maximum species‐level biomass was obtained under high survivorship. Species responded directionally to climatic variation, spatially separating differentially by plant traits (including height, reproduction, biomass, survival, leaf dry weight, and leaf area) consistently across all climates. Local soil variation drove stochastic trait responses across all species, with high levels of interactions occurring between site and species. This soil variability obscured climate‐driven responses: we recorded no directional trait responses for soil‐corrected traits like observed for climate‐corrected traits. Our species‐based approach contributes to our understanding of grassland community stabilization and suggests that these communities show some stability under climatic variation