Doctor of Philosophy, The Ohio State University, 2017, Psychology

Memory is an essential aspect of cognition, enabling us to retain information that can be used to guide decision-making and future planning. However, we often forget information due to proactive and retroactive interference from other, competing memories. Proactive interference occurs when new learning is more difficult as a result of previously acquired memories, whereas retroactive interference occurs when it is more difficult to remember previously acquired information as a result of new learning. Recent work has presented evidence that children are more vulnerable to interference effects than adults, experiencing dramatic levels of forgetting due to new learning. An essential question is what mechanisms modulate interference and changes in the magnitude of interference across development. This dissertation uses four experiments to examine factors modulating susceptibility to interference, including consolidation (i.e., the stabilization of memory traces across time) and memory binding (i.e., forming complex associations between multiple elements of an experience). Experiments 1 and 2 examined the effect of time delays on children's susceptibility to retroactive interference by comparing forgetting due to new learning upon immediate testing and following a 48-hr delay. The results indicated that children's retroactive interference was strong when memory was probed immediately after learning of new information, but was eliminated following a delay, suggesting a powerful role of consolidation in early memory development. Experiments 3 and 4 were designed to test whether memory binding processes might contribute to children's and adults' ability to resist interference effects. These experiments introduced a new paradigm to test interference and memory binding in 5- and 8-year-old children, as well as adults, and found evidence of decreased susceptibility to interference and improvements in memory binding across development. In addition, individual differences in (open full item for complete abstract)

Committee: Vladimir Sloutsky (Advisor); John Opfer (Committee Member); Per Sederberg (Committee Member) Subjects: Developmental Psychology; Psychology

Master of Arts, The Ohio State University, 2014, Psychology

Learning often affects future learning and memory for previously learned information by exerting either facilitation or interference effects. This work focuses on interference effects with the goal of better understanding memory development and mechanisms of such interference. In this study preschool-aged children and adults participated in a three-phased associative learning paradigm containing stimuli that were either unique or repeated across phases. Both age groups demonstrated interference effects, but only for repeated items. Proactive effects were comparable across age groups, whereas retroactive interference was much stronger in children. Retroactive interference increased in adults when contextual differences between phases were minimized (Experiment 2), and decreased in adults who were more successful at encoding repeated pairs of stimuli (Experiment 3). Together, these results suggest that configural encoding of stimuli may be an important mechanism of memory retention and memory development.

Committee: Vladimir Sloutsky (Advisor); John Opfer (Committee Member); Per Sederberg (Committee Member) Subjects: Behavioral Psychology; Cognitive Psychology; Developmental Psychology; Psychology

Doctor of Philosophy, Miami University, 2015, Psychology

Visual working memory (VWM) refers to the ability to actively maintain and use visual information for an ongoing process. It is a central component of many human abilities, and its limit in capacity constrains human performance across many tasks. VWM capacity is determined by actively maintaining and successfully retrieving information. Though many researchers have reached an agreement that VWM capacity is limited to 3 to 4 items, the neural mechanisms that account for this limit are still not well understood. In this dissertation, the ERP activities related to VWM maintaining process and retrieval process were investigated. Recently, an ERP study reported that the contralateral delay activity (CDA) was the ERP index of the number of items maintained in VWM. However, the assumption of hemispheric symmetry behind the study design is contradicted to those hemispheric asymmetry studies. Therefore, experiment 1 replicated the study about CDA to investigate the hemispheric symmetry issue particularly. Both the behavioral and ERP results indicated that there was hemispheric asymmetry during maintaining process and left hemisphere was more actively involved. Because of the hemispheric asymmetry during the maintaining process, experiment 2 was conducted to unveil the behavior of traditional P3 component in the standard change detection task. P3 derived from the maintaining process was sensitive to memory load as CDA was, and its amplitude was able to predict individual difference in VWM capacity estimated by Rouder et al.'s model. Besides the maintaining process, we also investigated the resolving of proactive interference (PI) during the retrieval process in experiment 3. Late positive component (LPC) was associated with resolving PI in the recent-probe design of the change detection task. The amplitude difference between recent and non-recent negative probe was negatively related to VWM capacity estimated from behavioral data. In summary, the P3 in the maintaining process (open full item for complete abstract)

Committee: Robin Thomas (Advisor); Joseph Johnson (Committee Member); Aaron Luebbe (Committee Member); Steven Wright (Committee Member) Subjects: Cognitive Psychology