35 research outputs found

    Circuit Breaker Module

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    The circuit breaker module for this design project is a proof of concept that demonstrates the functionality, feasibility, and attainability of a consumer grade power systems analysis device suitable for college laboratory use. The goal of this project was to create the final iteration of a module that has been developed and refined over the course of previous years. The Cal Poly Electrical Engineering Department intends to use this design to produce circuit breaker modules intended for fault analysis. With the current changes made to the previous modules, the current circuit breaker is lighter, safer, and more universally reproducible. The use of a generic plastic enclosure ensures that others outside of Cal Poly may find the means to build this module themselves. The redesign of the faceplate was done to prevent module users from touching exposed live wires when trying to reach the mechanical switch. Finally, more affordable, adequate component alternatives were found so that Cal Poly will be able to reproduce this design for years to come

    Effects of Prior Knowledge on Memory: Implications for Education

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    The encoding, consolidation, and retrieval of events and facts form the basis for acquiring new skills and knowledge. Prior knowledge can enhance those memory processes considerably and thus foster knowledge acquisition. But prior knowledge can also hinder knowledge acquisition, in particular when the to-be-learned information is inconsistent with the presuppositions of the learner. Therefore, taking students' prior knowledge into account and knowing about the way it affects memory processes is important for optimization of students' learning. Recent behavioral and neuroimaging experiments have shed new light on the neural mechanisms through which prior knowledge affects memory. However, relatively little is known about developmental differences in the ability to make efficient use of one's knowledge base for memory purposes. In this article, we review and integrate recent empirical evidence from developmental psychology and cognitive neuroscience about the effects of prior knowledge on memory processes. In particular, this may entail an extended shift from processing in the medial temporal lobes of the brain toward processing in the neocortex. Such findings have implications for students as developing individuals. Therefore, we highlight recent insights from cognitive neuroscience that call for further investigation in educational settings, discussing to what extent these novel insights may inform teaching in the classroom

    Neural activation patterns during retrieval of schema-related memories: Differences and commonalities between children and adults

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    Schemas represent stable properties of individuals’ experiences, and allow to classify new events as being congruent or incongruent with existing knowledge. Research with adults indicates that the prefrontal cortex (PFC) is involved in memory retrieval of schema-related information. However, developmental differences between children and adults in the neural correlates of schema-related memories are not well understood. One reason for this is the inherent confound between schema-relevant experience and maturation, as both are related to time. To overcome this limitation, we used a novel paradigm that experimentally induces, and then probes for task-relevant knowledge during encoding of new information. Thirty-one children aged 8–12 years and 26 young adults participated in the experiment. While successfully retrieving schema-congruent events, children showed less medial PFC activity than adults. In addition, medial PFC activity during successful retrieval correlated positively with children’s age. While successfully retrieving schema-incongruent events, children showed stronger hippocampus (HC) activation as well as weaker connectivity between the striatum and the dorsolateral PFC than adults. These findings were corroborated by an exploratory full-factorial analysis investigating age differences in the retrieval of schemacongruent versus schema-incongruent events, comparing the two conditions directly. Consistent with the findings of the separate analyses, two clusters, one in the medial PFC, one in the HC, were identified that exhibited a memory x congruency x age group interaction. In line with the two-component model of episodic memory development, the present findings point to an age-related shift from a more HC-bound processing to an increasing recruitment of prefrontal brain regions in the retrieval of schema-related events

    Does one year of schooling improve children's cognitive control and alter associated brain activation?

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    The “5-to-7-year shift” refers to the remarkable improvements observed in children’s cognitive abilities during this age range, particularly in their ability to exert control over their attention and behavior—that is, their executive functioning. As this shift coincides with school entry, the extent to which it is driven by brain maturation or by exposure to formal schooling is unclear. In this longitudinal study, we followed 5-year-olds born close to the official cutoff date for entry into first grade and compared those who subsequently entered first grade that year with those who remained in kindergarten, which is more play oriented. The first graders made larger improvements in accuracy on an executive-function test over the year than did the kindergartners. In an independent functional MRI task, we found that the first graders, compared with the kindergartners, exhibited a greater increase in activation of right posterior parietal cortex, a region previously implicated in sustained attention; increased activation in this region was correlated with the improvement in accuracy. These results reveal how the environmental The “5-to-7-year shift” refers to the remarkable improvements observed in children’s cognitive abilities during this age range, particularly in their ability to exert control over their attention and behavior—that is, their executive functioning. As this shift coincides with school entry, the extent to which it is driven by brain maturation or by exposure to formal schooling is unclear. In this longitudinal study, we followed 5-year-olds born close to the official cutoff date for entry into first grade and compared those who subsequently entered first grade that year with those who remained in kindergarten, which is more play oriented. The first graders made larger improvements in accuracy on an executive-function test over the year than did the kindergartners. In an independent functional MRI task, we found that the first graders, compared with the kindergartners, exhibited a greater increase in activation of right posterior parietal cortex, a region previously implicated in sustained attention; increased activation in this region was correlated with the improvement in accuracy. These results reveal how the environmental context of formal schooling shapes brain mechanisms underlying improved focus on cognitively demanding tasks

    The influence of prior knowledge on memory: A developmental cognitive neuroscience perspective

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    Across ontogenetic development, individuals gather manifold experiences during which they detect regularities in their environment and thereby accumulate knowledge. This knowledge is used to guide behavior, make predictions, and acquire further new knowledge. In this review, we discuss the influence of prior knowledge on memory from both the psychology and the emerging cognitive neuroscience literature and provide a developmental perspective on this topic. Recent neuroscience findings point to a prominent role of the medial prefrontal cortex (mPFC) and of the hippocampus (HC) in the emergence of prior knowledge and in its application during the processes of successful memory encoding, consolidation, and retrieval. We take the lateral PFC into consideration as well and discuss changes in both medial and lateral PFC and HC across development and postulate how these may be related to the development of the use of prior knowledge for remembering. For future direction, we argue that, to measure age differential effects of prior knowledge on memory, it is necessary to distinguish the availability of prior knowledge from its accessibility and use

    Knowledge Acquisition During Exam Preparation Improves Memory and Modulates Memory Formation

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    According to the schema-relatedness hypothesis, new experiences that make contact with existing schematic knowledge are more easily encoded and remembered than new experiences that do not. Here we investigate how real-life gains in schematic knowledge affect the neural correlates of episodic encoding, assessing medical students 3 months before and immediately after their final exams. Human participants were scanned with functional magnetic resonance imaging while encoding associative information that varied in relatedness to medical knowledge (face–diagnosis vs face–name pairs). As predicted, improvements in memory performance over time were greater for face–diagnosis pairs (high knowledge-relevance) than for face–name pairs (low knowledge-relevance). Improved memory for face–diagnosis pairs was associated with smaller subsequent memory effects in the anterior hippocampus, along with increased functional connectivity between the anterior hippocampus and left middle temporal gyrus, a region important for the retrieval of stored conceptual knowledge. The decrease in the anterior hippocampus subsequent memory effect correlated with knowledge accumulation, as independently assessed by a web-based learning platform with which participants studied for their final exam. These findings suggest that knowledge accumulation sculpts the neural networks associated with successful memory formation, and highlight close links between knowledge acquired during studying and basic neurocognitive processes that establish durable memories.  SIGNIFICANCE STATEMENT In a sample of medical students, we tracked knowledge accumulation via a web-based learning platform and investigated its effects on memory formation before and after participants' final medical exam. Knowledge accumulation led to significant gains in memory for knowledge-related events and predicted a selective decrease in hippocampal activation for successful memory formation. Furthermore, enhanced functional connectivity was found between hippocampus and semantic processing regions. These findings (1) demonstrate that knowledge facilitates binding in the hippocampus by enhancing its communication with the association cortices, (2) highlight close links between knowledge induced in the real world and basic neurocognitive processes that establish durable memories, and (3) exemplify the utility of combining laboratory-based cognitive neuroscience research with real-world educational technology for the study of memory

    Specifying the role of the ventromedial prefrontal cortex in memory formation

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    Recent neuroimaging research suggests that the ventromedial prefrontal cortex (vmPFC) plays an important role for successful memory formation that takes place in the context of activated prior knowledge. These findings led to the notion that the vmPFC integrates new information into existing knowledge structures. However, a considerable number of neuroimaging studies that have investigated memory formation in the context of prior knowledge have not found vmPFC involvement. To resolve this inconsistency, we propose a distinction between knowledge-relevance (the degree to which new information can be linked to prior knowledge) and knowledge-congruency (the perceived match between prior knowledge and the to-be-encoded information). We hypothesized that the vmPFC contributes to successful memory formation only when perceived knowledge-congruency is high, independent of knowledge-relevance. We tested this hypothesis in a design that varied both congruency and relevance during memory encoding, which was performed in the MR scanner. As predicted, the results showed that vmPFC contributions to memory formation vary as a function of knowledge-congruency, but not as a function of knowledge-relevance. Our finding contributes to elucidating the seemingly inconsistent findings in the literature and helps to specify the role of the vmPFC in memory formation. (DIPF/Orig.

    Are there age-related differences in the effects of prior knowledge on learning? Insights gained from the memory congruency effect

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    Humans accumulate knowledge throughout their entire lives. In what ways does this accumulation of knowledge influence learning of new information? Are there age-related differences in the way prior knowledge is leveraged for remembering new information? We review studies that have investigated these questions, focusing on those that have used the memory congruency effect, which provides a quantitative measure of memory advantage because of prior knowledge. Regarding the first question, evidence suggests that the accumulation of knowledge is a key factor promoting the development of memory across childhood and counteracting some of the decline in older age. Regarding the second question, evidence suggests that, if available knowledge is controlled for, age-related differences in the memory congruency effect largely disappear. These results point to an age-invariance in the way prior knowledge is leveraged for learning new information. Research on neural mechanisms and implications for application are discussed

    A boon and a bane: comparing the effects of prior knowledge on memory across the lifespan

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    We tested 6–7-year-olds, 18–22-year-olds, and 67–74-year-olds on an associative memory task that consisted of knowledge-congruent and knowledge-incongruent object–scene pairs that were highly familiar to all age groups. We compared the three age groups on their memory congruency effect (i.e., better memory for knowledge-congruent associations) and on a schema bias score, which measures the participants’ tendency to commit knowledge-congruent memory errors. We found that prior knowledge similarly benefited memory for items encoded in a congruent context in all age groups. However, for associative memory, older adults and, to a lesser extent, children overrelied on their prior knowledge, as indicated by both an enhanced congruency effect and schema bias. Functional Magnetic Resonance Imaging (fMRI) performed during memory encoding revealed an age-independent memory x congruency interaction in the ventromedial prefrontal cortex (vmPFC). Furthermore, the magnitude of vmPFC recruitment correlated positively with the schema bias. These findings suggest that older adults are most prone to rely on their prior knowledge for episodic memory decisions, but that children can also rely heavily on prior knowledge that they are well acquainted with. Furthermore, the fMRI results suggest that the vmPFC plays a key role in the assimilation of new information into existing knowledge structures across the entire lifespan. vmPFC recruitment leads to better memory for knowledge-congruent information but also to a heightened susceptibility to commit knowledge-congruent memory errors, in particular in children and older adults
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