작업기억 집행기능에 관여하는 뇌 영역과 연결망의 메타분석 및 교육적 시사점

마서민 전북대학교 일반대학원 2021 국내박사

Working memory underpins cognitive development, learning and education. Among the components of working memory, the central executive system is considered as a universal attentional control system, endowed with a wide range of higher cognitive functions. Therefore, the purpose of this study is to explore the brain regions and networks correlated to executive functions in working memory through meta-analysis of fMRI neuroimaging studies, and to derive educational implications. In order to collect fMRI data on executive functions of working memory, electronic journals were used to search for literature reporting Talairach or MNI standard coordinates of healthy subjects from the year of 2000 to 2020. Finally, 104 studies and 132 experiments were included. The coordinate-based meta-analysis of Activation Likelihood Estimation(ALE) was used to detect the significant activation regions related to the executive functions and processing contents of working memory. MACM(Meta-Analytic Connectivity Modeling) analysis was also performed to measure functional connectivity in activated regions related to the overall executive function of working memory. Data analysis by using GingerALE 3.0.2, and the activated brain regions and connectivity networks were visualized by Mango 4.0.1 and BrainNet Viewer 1.7. The results are summarized as follows. First, the brain regions related to the overall executive functions of working memory showed a distribution pattern of fronto-parietal networks. They were mainly concentrated in the left superior frontal gyrus(BA 6), the left inferior parietal lobule(BA 40), the right superior parietal lobule(BA 7), the right precuneus(BA7), and the bilateral insula(BA 13). Second, large areas of activation in the frontal and parietal lobes were confirmed by analysis of three executive function types (updating, inhibition, and shifting). This suggests that executive function is based on a network of front and post brain regions, rather than being supported only by the frontal lobes. In addition to activating the left inferior parietal lobule (BA 40), the three executive function types also have dependent brain regions. This indicates that the brain activity of executive function has the characteristics of unity and diversity. Third, the activation in both frontal and parietal regions were found according to the analysis of the three processing content types of working memory (language, object and spatial). Unlike working memory maintenance, content selection does not involve hemispheric separation during the execution of working memory. Fourth, the use of different types of processing content for each executive function showed different patterns of brain activity, but they all activated the prefrontal cortex together. The prefrontal cortex provides a top-down signal in the executive function of working memory to control and regulate the activity in other brain regions, including the parietal lobe, the basal nerve, and the limbic system. Fifth, the six important nodes reported in the overall executive function of working memory, namely the left superior frontal gyrus, the left inferior parietal lobule, the right superior parietal lobule, the right precuneus, the left and right insula, are analyzed for collaborative connectivity network. Beyond the restriction of working memory tasks, the six nodes were found to be functionally connected to the middle temporal gyrus, fusiform gyrus, and basal ganglia, including thalamus, caudate nucleus, and lentiform nucleus. Therefore, in the process of working memory exerting related cognitive functions, it also needs the participation of the perceptual system and the motor system. Based on the results of the study, some suggestions are put forward to help students develop working memory ability and executive function ability. In addition, in the longer term, teachers have the obligation and responsibility to understand the internal mechanism of learning according to the law of brain development, so as to find appropriate teaching methods.

Effects of Instructional Scaffolding and Working Memory on the Mathematical Problem-Solving Skills of Middle School Students

황신림 전남대학교 2025 국내석사

This study aims to explore how cognitive strategy scaffolding and metacognitive strategy scaffolding influence the mathematical problem-solving abilities in Middle school students with mathematical difficulties who possess different working memory characteristics. Based on existing literature, the study proposes three core hypotheses: (1) Scaffolding type has a significant main effect on mathematical problem-solving ability, with metacognitive strategy scaffolding being more effective in complex problem-solving; (2) The three subsystems of working memory (central executive function, phonological loop, and visuospatial sketchpad) have significant main effects on mathematical performance, with central executive function having a particularly pronounced impact on solving complex mathematical problems; (3) There is an interaction effect between scaffolding type and working memory capacity, and different scaffolds have differential impacts on students with high and low working memory levels.This study employed a 3×2 nonequivalent control group pretest-posttest design with 144 ninth-grade students experiencing difficulties in mathematics as participants, to investigate the impact of instructional scaffolding type (cognitive scaffolding, metacognitive scaffolding, control group) and working memory characteristics (central executive function, phonological loop, visuospatial sketchpad) on mathematical problem-solving ability. Working memory capacity was assessed using the N-back task, digit span test, and Shape transformation test. The intervention effects were examined using covariance analysis, controlling pretest scores and learning time. The study found that instructional scaffolding had a significant main effect on mathematical problem-solving ability, with metacognitive scaffolding outperforming cognitive scaffolding overall. All three components of working memory significantly impacted mathematical problem-solving ability. There was a significant interaction effect between instructional scaffolding type and working memory characteristics. For students with low central executive function, metacognitive scaffolding was significantly more effective than cognitive scaffolding. In contrast, for students with low phonological loop and low visuospatial sketchpad function, the two types of scaffolding were equally effective. The findings of this study suggest that instructional design should fully consider students' working memory characteristics and provide targeted support for students with different cognitive profiles. When students are primarily limited by the central executive function, metacognitive scaffolding can offer more effective support. In contrast, when students are mainly restricted by basic information-processing components (phonological loop or visuospatial sketchpad), cognitive scaffolding is more effective. This differentiated pattern provides a scientific basis for developing personalized teaching strategies. Future research could explore the long-term effects and transferability of scaffolded instruction, as well as its application in a broader range of subjects and task contexts. Keywords: Working memory, Instructional scaffolding, Metacognitive scaffolding, Mathematical problem-solving ability 21세기 인재 양성의 핵심 요소인 수학 문제해결 능력은 수학을 어려워하는 학생들에게 특히 중요하다. 교육 스캐폴딩은 효과적인 교육 전략으로, 학생들의 인지 부담을 줄이고 맞춤형 지원을 제공할 수 있다. 그러나 다양한 작업 기억 특성을 가진 수학적인 어려움을 호소하는 학생들을 대상으로 적절한 스캐폴딩 유형을 선택하는 방법에 대한 심층 연구는 여전히 부족하다. 따라서 인지 스캐폴딩과 메타인지 스캐폴딩이 서로 다른 작업 기억 특성을 가진 학생들에게 미치는 차별화된 영향에 대한 탐구가 필요하다. 본 연구는 3×2 비등가대조군의 사전-후측 설계를 채택하였으며, 중국 구이저우성 중학생 중 수학곤란 학생 144명을 연구대상으로 선정하여 교수 스캐폴딩 유형(인지 스캐폴딩, 메타인지 스캐폴딩, 대조군)과 작업 기억 특성(중앙 실행 기능, 음성 순환, 시공간 스케치판)이 수학 문제 해결 능력에 미치는 영향을 탐구하였다. N-back 작업, 디지털 광도 테스트 및 그래픽 변환 테스트를 통해 표본의 작업 기억 능력을 평가하고 공분산 분석을 사용하여 개입 효과를 테스트하였으며, 사전 테스트 결과와 학습 시간의 영향을 제어하였다. 연구의 결과에 따르면, (1) 교수 스캐폴딩는 수학 문제 해결 능력에 상당한 주효과가 있으며 메타인지 스캐폴딩의 전반적인 효과는 인지 스캐폴딩보다 우수하였다. (2) 작업 기억의 세 가지 구성 요소는 모두 수학 문제 해결 능력에 상당한 영향을 미치는 것으로 확인되었다. (3) 교수 스캐폴딩의 유형과 작업 기억 특성 사이에는 상당한 상호 작용 효과가 있으며, 중앙 실행 기능이 낮은 학생의 경우, 메타인지 스캐폴딩의 효과가 인지 스캐폴딩보다 훨씬 우수하였다. 반면, 음성 순환 또는 시공간 스케치판 능력이 낮은(저음성 순환 및 저시공간 스케치판) 학생들의 경우, 두 스캐폴딩 유형 간 효과 차이는 유의미하지 않았다. 이에 따라, 교육 설계는 학생의 작업 기억 특성을 충분히 고려해야 하며, 다양한 인지 특성을 가진 학생들에게 맞춤형 스캐폴딩 지원을 제공해야 한다. 또한, 학생이 주로 중앙 실행 기능에 제한을 받을 때, 메타인지 스캐폴딩이 더 효과적이며, 기초 정보 처리 능력에 제한을 받을 때는 적절한 스캐폴딩 유형을 신중하게 선택해야 한다. 이상과 같은 연구의 결과는 개인화된 수학 교육 전략을 개발하기 위한 과학적 근거를 제공할 수 있을 것이다. 주요어: 스캐폴딩, 작업 기억, 수학 문제해결 능력, 메타인지 스캐폴딩

Process-switch in Working Memory Impose Significant Cost to Its Performance

최민진 서울대학교 대학원 2021 국내석사

Working memory is widely accepted to be limited in capacity, but how various aspects of memorized items affect working memory capacity and performance continues to be of great interest to many neuroscientists. A recent breakthrough in the field shows that working memory resources are flexibly distributed among numbers of items that need to be maintained. The allocation of resources is modulated by how much attention the item is given. Although the new framework presents useful insights, a more natural setting in working memory utilization often requires more than simple maintenance of multiple items—it requires updates that involve manipulation of memory. This thesis contains a series of investigations of memory updates on working memory performance using the established techniques of psychophysics and mixed linear regression. First, we perform a working memory update task on 102 individuals. We find a unique cost previously underestimated in the working memory behavioral paradigm—the cost of switching between working memory process modes. We show that the switch has a significant and substantial effect on the error, and it has a positive multiplicative relationship with the number of other concurrently maintained representations. Second, we show that the standard deviation estimate ( ) from a classic decision-making task is correlated with the estimate from the orientation estimation, supporting the use of SD estimate from the decision-making task in place of one from estimation. Additionally, we show that the decision-making paradigm allows a trial-to-trial measure of performance in response time, which has important implications for future analysis. Third, we develop a unique experiment paradigm inspired by the given experiments and test its potential for uncovering a novel and essential aspect of the switch between different operational modes of working memory (maintenance and manipulation). We find some indication that the source of the main cost in performance is the process-switch itself. Simultaneously, the processes—retrieval and manipulation of an item—do not affect working memory performance as expected. We show that 1. the cost of manipulating a target is increased when the non-target item is retrieved, 2. the target item’s memory is impaired when the non-target item is manipulated, 3. the cost of manipulating an additional item is negligible if the other item in memory is already manipulated. The results suggest that modulating between the ‘maintenance network'—activated by the ‘retrieval’ process—and the ‘manipulation network'—activated by the ‘manipulation’ process—incurs the greatest cost in working memory performance. In conclusion, our findings suggest that the process-switch and not the processes themselves incur a great cost in working memory. More importantly, we devised an exciting novel experimental paradigm that can be utilized to study the top-down executive control of modular working memory more readily. Working memory is widely accepted to be limited in capacity, but how various aspects of memorized items affect working memory capacity and performance continues to be of great interest to many neuroscientists. A recent breakthrough in the field shows that working memory resources are flexibly distributed among numbers of items that need to be maintained. The allocation of resources is modulated by how much attention the item is given. Although the new framework presents useful insights, a more natural setting in working memory utilization often requires more than simple maintenance of multiple items—it requires updates that involve manipulation of memory. This thesis contains a series of investigations of memory updates on working memory performance using the established techniques of psychophysics and mixed linear regression. First, we perform a working memory update task on 102 individuals. We find a unique cost previously underestimated in the working memory behavioral paradigm—the cost of switching between working memory process modes. We show that the switch has a significant and substantial effect on the error, and it has a positive multiplicative relationship with the number of other concurrently maintained representations. Second, we show that the standard deviation estimate ( ) from a classic decision-making task is correlated with the estimate from the orientation estimation, supporting the use of SD estimate from the decision-making task in place of one from estimation. Additionally, we show that the decision-making paradigm allows a trial-to-trial measure of performance in response time, which has important implications for future analysis. Third, we develop a unique experiment paradigm inspired by the given experiments and test its potential for uncovering a novel and essential aspect of the switch between different operational modes of working memory (maintenance and manipulation). We find some indication that the source of the main cost in performance is the process-switch itself. Simultaneously, the processes—retrieval and manipulation of an item—do not affect working memory performance as expected. We show that 1. the cost of manipulating a target is increased when the non-target item is retrieved, 2. the target item’s memory is impaired when the non-target item is manipulated, 3. the cost of manipulating an additional item is negligible if the other item in memory is already manipulated. The results suggest that modulating between the ‘maintenance network'—activated by the ‘retrieval’ process—and the ‘manipulation network'—activated by the ‘manipulation’ process—incurs the greatest cost in working memory performance. In conclusion, our findings suggest that the process-switch and not the processes themselves incur a great cost in working memory. More importantly, we devised an exciting novel experimental paradigm that can be utilized to study the top-down executive control of modular working memory more readily.

Working Memory in English Speech Production : Native Speakers vs. Korean EFL Learners

이옥영 서울대학교 대학원 2020 국내박사

본 논문은 멀티태스킹을 하면서 말을 할 때 말소리가 어떻게 변화하는지 살펴봄으로써, 작업기억이 발화의 말소리 생성에 관여하는지를 모국어와 외국어로서의 영어 발화를 비교하여 연구하였다. 이는 선행 연구에서 발화시 말소리 생성이 두뇌의 작업기억 시스템을 통해 계획되고 처리된다고 설명함에도 불구하고, 직접적인 실증 근거가 없고 간접적인 자료들이 반증한다는 점에서 출발하였다. 우선, 인지적 요인들이 리듬과 억양으로 정의되는 운율의 설명되지 않는 변이와 관련이 있을 것이라는 추측이 제기되어 왔지만, 이런 인지와 발화 사이의 연관성은 여전히 추측일 뿐 실증적 자료는 아직 제시되지 않았다. 게다가, 심리언어학에서 널리 수용되는 발화 모델들에서, 소리 정보의 일시적 저장 및 능동적 조작이 작업기억을 통해 처리된다고 설명하고 있지만, 역시 직접적 실험 근거가 없고, 특히 음운-음성적 발화 단계에 대한 해당 이론의 설명이 부분적일 뿐임을 인정하였고, 장기기억에 저장된 조음 뭉치를 그대로 출력해서 사용한다는 설명을 혼합함으로써, 작업기억이 필수적인지 의문을 남겼다. 아울러, 기억 이론 관점에서의 선행연구 리뷰 역시 작업기억이 말소리 생성에는 관여하지 않을지도 모른다는 잠정적 결론에 이르렀다. 마지막으로, 만약 말소리 생성이 작업기억을 통해 이루어지는지 아닌지 결정 여부가, 실시간으로 능동적으로 계획하며 만들어 발음하는 것인지 아니면 이미 저장된 발음 루틴을 습관적이고 반사적으로 출력하는 것인지에 달려 있다면, 원어민들과 외국어 학습자들이 다른 발화 처리 과정을 거칠지도 모른다는 추측을 하게 되었다. 따라서, 본 연구는 영어 발화의 말소리 생성에 작업기억이 연관되어 있는지, 그리고 영어 모국어 화자와 외국어 학습자가 다른 패턴을 보이는 지의 두 질문을 직접적으로 실험하였다. 미국인들과 한국인들이 각각 의미와 통사형태적으로 친숙해진 영어 문장들을 언어 혹은 공간 과제를 동시에 수행하는 멀티태스킹 상황에서 소리내어 말했다. 이들은 또한 같은 영어 문장들을 오직 말만 하는 비-멀티태스킹 상황에서 대조군으로 발화했다. 실험 결과 미국인들과 한국인들은 작업기억에 부과되는 인지 부하에 따라 다른 발화 패턴을 보였다. 우선 미국인과 한국인 모두 말을 하면서 멀티태스킹을 하게 되면 말실수를 더 많이 하고 더 빨리 말했다. 미국인들은 말을 하면서 멀티태스킹한 과제가 언어 과제이든 공간 과제이든 상관없이 같은 말소리 패턴을 보였으며, 측정한 그 외 모든 운율적 특성에서 말만 할 때와 통계적으로 동일했다. 그러나 대조적으로, 한국인들은 말하면서 언어 과제를 동시에 했을 때 발음에 큰 어려움을 보였다. 언어 과제를 할 때는 말만 할 때 뿐만 아니라 공간 과제를 할 때와 비교해서도 말실수가 더 많았고 운율이 평소와 더 많이 달라졌다. 공간 과제와 말을 멀티태스킹할 때는 앞서 말한 더 많은 말실수와 더 빠른 말속도 외에 다른 어떤 말소리의 차이를 보이지 않은 반면, 언어 과제와 말을 멀티태스킹할 때는 말 실수도 훨씬 더 많이 하고, 훨씬 더 빨리 말하고, 명사나 동사와 관사 등의 단어들 길이가 더 비슷해지고, 모음을 좀 더 웅얼거리며 발음했다. 본 논문은 이 실험 결과를 다음과 같이 해석한다. 작업기억은 말소리 생성에 관여할 수도 하지 않을 수도 있다. 이는 화자가 해당 언어에 대해 가지는 언어 경험과 훈련의 양과 그에 따라 장기 기억에 저장된 정보의 양에 따라 결정된다. 이는 해당 실험에서는 이분법적으로 나타났으나 실제로는 점진적인 선형 관계일 수도 있다. 이분법적으로 설명하자면, 모국어 성인 화자는 다년간의 언어 경험과 발음 훈련을 통해 이미 단어 형태와 조음 정보가 쌍으로 엮여 장기 기억에 루틴화된 템플릿 형태로 존재함으로써, 실제 발음을 할 때는 시각적 혹은 개념적으로 주어진 단어 형태를 실시간으로 조작하여 발음을 계획하고 시행하지 않는다. 즉각적이고 자동적으로 장기기억에서 저장된 형태-조음을 직접 출력해서 반사적으로 발음하게 되기 때문에, 작업기억을 통한 정보 처리는 이루어지지 않는다. 반면, 외국어로 언어를 배우는 학습자는, 그 언어 경험이 상당히 제한적이고, 특히 많은 경우 말하기 경험에서 더욱 그러하기에, 언어 형태와 조음 정보가 단단하게 장기 기억에 묶음으로 저장되어 있지도 않고 조음기관 훈련도 반사적으로 즉각적으로 이루어질 만큼은 아닐 확률이 높다. 따라서 할 말이 이미 의미, 문법, 단어, 형태적으로 모두 준비된 상태라 하더라도, 이를 발음하는 일 조차 실시간으로 계획되고 조작된다. 작업기억이 필요한 것이다. 이를 바탕으로 본 논문은 두뇌 기억 시스템의 작업기억과 장기기억과 관련하여 모국어와 외국어 말소리 생성에 대한 모델을 제시한다. 또한, 오랫동안 실증적 자료 없이 상반되는 추측에 그친 작업기억과 발화 말소리 생성의 관계를 직접적인 실험을 통해 검증을 시도했다는 점, 언어 운율에 대한 변이 중 멀티태스킹 시 발생할 수 있는 운율 변화를 인지와 연결하여 설명한 점, 상반된 선행연구의 추측과 논의들이 실제로는 해당 언어에 대한 경험과 훈련에 바탕을 두면 일관적으로 설명될 수 있음을 제안한 점, 그리고 이것이 모국어 대 외국어 혹은 나아가 모국어 어린이와 외국어 초급 학습자 대 모국어 성인과 외국어 숙련자로 확대하여 말소리 생성의 정보 처리 모델 및 교육적 함의를 제시한다는 점 등에서, 본 논문은 의의를 갖는다. 주요어 : 작업기억, 작업기억 능력, 발화, 운율, 음운적-음성적 부호화, 검색, 모국어 대 외국어 학 번 : 2006-30916 This dissertation investigates how speech sounds may change as a function of varying working memory load during speech. While cognitive factors have long been suspected to influence speech sounds, being responsible for unexplained variability in speech prosody, the hypothesized connection between cognition and speech production has yet to be systematically theorized with empirical data. Despite the widely accepted assumption in psycholinguistics that working memory involves speech production for temporary maintenance and active manipulation of speech information, the sound planning process remains an open question. Production models not only acknowledge that they only partially account for the phonological-phonetic encoding processes, but production models also adopt direct retrieval of memorized articulatory routines from long-term memory that may allow speakers to bypass the working memory process. Moreover, a comprehensive review from a memory perspective requires direct evidence and reexamination of the psycholinguistic assumption, suggesting that there is no working memory used in speech production. Furthermore, if the key lies between active ongoing planning and automatic routined response, then native speakers and nonnative speakers of a language may reveal different production patterns. These speaker types and their production patterns have not yet been directly compared in the literature. To address this gap, this study asks whether working memory is involved in English speech production and whether the involvement differs between native (first-language, L1) and nonnative (second-language, L2) speakers of English. To explore how cognitive processing overload derails typical speech sounds, in this study I experimentally manipulated the amount and the type of cognitive load in working memory by having participants engage in multitasking while speaking. Native speakers of American English and Korean EFL learners of English produced a set of syntactically complex sentences under two working memory load conditions and two control conditions. In the load conditions, speakers engaged in an additional task that taxed either verbal or spatial working memory while speaking. In the control no-load conditions, they solved an equation before speaking. The results show different working memory influences on L1 vs. L2 speech production. Both the L1 and the L2 speech had more errors and were faster during multitasking. However, the effect of load type was different. The L1 speech remained similarly intact, regardless of whether the task was verbal or spatial. By contrast, the L2 speech was impaired only by the verbal task; speech produced during a concurrent verbal task became more erroneous, faster, less variable in word durations, and less distinctive in vowel quality. The spatial task did not impact L2 prosody. I interpret these results as suggesting that different cognitive processes underly L1 and L2 speech production. This dissertation proposes a tentative model for L1 and L2 speech production with direct reference to working memory versus long-term memory. L1 speech production is usually automatic and spontaneous via retrieval from long-term memory and not impacted by (verbal) working memory. Thanks to sufficient exposure to and practice of form-sound units, speech production directly accesses long-term memory and instantly executes the articulatory gestural routines that are already stored along with the lexical forms. As L1 speech production draws from long-term memory, working memory is not overloaded by a (verbal or spatial) working memory task, and speech becomes only more erroneous and faster due to divided attention within a set time frame. By contrast, L2 speech sounds mainly emerge on the go via phonological-phonetic encoding in (verbal) working memory. Due to limited language experience in L2, articulatory templates are often not fully developed or readily retrievable for automatic execution. As L2 speech production draws from verbal working memory, a concurrent verbal task, but not a spatial task, overloads the capacity-limited verbal working memory component. While a general effect of divided attention can be observed just as in most multitasking, a verbal task disrupts speech more significantly than a non-verbal task. The study contributes direct evidence regarding the relationship between working memory and speech production. I examine some speculated effects of cognitive load on prosodic variations and move toward resolving the controversy over the encoding and the retrieval processes by referring to language experience. Beyond the scope of this dissertation and as a guidepost for research, we need to investigate how speech production processes may develop as a function of L1 language experience and L2 proficiency. Keywords: working memory, working memory capacity, speech production, prosody, phonological-phonetic encoding, retrieval, L1 versus L2 Student Number: 2006-30916

Neural Bases of Phonological Working Memory

Scott, Terri L ProQuest Dissertations & Theses Boston University 2020 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Phonological working memory (PWM) is the mind's capacity for maintaining and manipulating representations of the sounds important for speech when they are not actively being perceived. It is believed to be a critical component supporting typical language acquisition and vocabulary development, as well as second-language learning. Despite the success of the theoretical framework traditionally used to conceptualize PWM, consensus on its instantiation in the brain remains elusive. In this thesis, I will describe a series of studies designed to interrogate the functionality of the brain regions supporting PWM. In Chapter 1, we compare activation patterns from a canonical PWM task, nonword repetition, to nonword discrimination, a matched task designed to engage core PWM functions, but for the purpose of comparing stimuli, not repeating them. We replicate the findings that PWM during nonword repetition engages speech cortices and show that these cortical regions are also reliably engaged in nonword discrimination, in individual subjects. In Chapter 2, we directly assess the extent to which conjunctive activation between language and working memory paradigms can be interpreted as shared functionality. We find that despite the ability to localize regions in which the majority of subjects show conjunction of significant activation between tasks, the pattern similarity between tasks within those regions vary. We find no pattern similarity between language and spatial working memory, and marginal similarities between language and verbal working memory. Verbal working memory and spatial working memory conjunctions localize a similar network to the multiple demand network and find highly similar patterns of activation in these regions across working memory tasks. Finally, in Chapter 3, we investigate the functional properties of brain areas supporting PWM by comparing activation between nonword repetition, language, verbal working memory, and spatial working memory tasks. We find that PWM shares support with areas involved in spoken language perception, as well as regions engaged by working memory tasks that lie outside of the core language network. Taken together, these studies give a detailed account of the neural bases of PWM, through the lens of shared functionality between this capacity, language, and other domains of working memory.

The Effects of Recasts and Working Memory on Learning English Past Tense Forms : 오류 고쳐 말하기와 작업기억이 영어 과거 동사 습득에 미치는 영향

김소원 배재대학교 대학원 2015 국내석사

A number of studies over the past 20 years have investigated the effects of recasts on second language (L2) learning, but showed inconclusive findings. The present study examined the effects of recasts on English past tense learning in relation to individual differences in working memory. Forty-two Korean university students were placed into the recast group and the control group, took a pretest and two types of working memory tests, and participated in five sessions of conversational interactions with the researcher for two-way communicative tasks. During the interactions, recasts were provided as a treatment in response to their error-containing utterances. After the sessions with the treatment, a posttest and a questionnaire were carried out. The results from a chi-square analysis showed that recasts were effective on learning past tense forms. A logistic regression analysis also revealed that recast was a significant indicator of progress in past tense learning. However, working memory did not predict the posttest results. A post-hoc analysis found that recasts had significant effects on learning irregular past tense, and learners’ prior grammatical knowledge was a significant predictor of progress in regular past tense learning. These results indicate that type of linguistic target form may influence the effectiveness of recasts and learners' differential levels of grammatical knowledge may play a role in English past tense learning.

(The) influence of working memory on visual search efficiency : visual search does not remain efficient when working memory is working

한상훈 Graduate School, Yonsei University 2003 국내석사

방해자극 사이에서 탐색자극을 찾아내는 시각탐색 과정에 작업기억이 개입하는가? 시각탐색과는 무관한 정보가 작업기억 내에 유지, 조작되는 상황에서 탐색의 효율성이 변화하는지의 여부를 알아보았다. 최근 Woodman 등 (2001)은, 시각탐색의 효율성, 즉 시각 탐색 그래프의 기울기가 시각적 자극을 작업기억에 유지하면서 시각탐색을 하건, 단독으로 시각탐색을 수행하건 일정하게 나타남을 보임으로써 작업기억과 선택적 주의가 요구되는 시각탐색과정이 밀접한 관련을 맺고 있지 않다고 주장한 바 있다. 하지만, 그들의 연구에서의 작업기억에 대한 조작은 시각적인 단기기억 저장에 국한되어 있다. Baddeley와 Hitch (1974)의 연구를 시작으로 작업기억은 단기 저장 기능뿐 아니라, 기억 정보에 대한 집행기능과도 관련되어 있음을 많은 연구에서 밝힌 바 있다. 본 연구에서는 Woodman 등이 사용한 이중과제 패러다임을 수정하여, 작업기억에서 정보를 유지하는 것뿐 아니라 계속적으로 기억 정보를 조작해야 하는 조건 하에서 시각탐색 기울기가 변화하는지 살펴보았다. 실험 1에서 작업기억 내에 계속적인 정보의 유지 및 조작이 이루어질 수 있도록 참가자는 매 시행마다 무선적으로 추출되어 제시되는 세 자리 숫자를 기억하고 계속해서 3씩 빼나가는 역행 숫자세기 과제(Backward Counting)를 수행하였으며, 그 중간에 시각탐색을 수행하였다 (이중과제). 또 다른 기억과제를 사용한 실험 2에서, 실험 참가자들은 무선적인 순서로 제시되는 알파벳 4개를 기억하고 이를 알파벳 순서로 재배열하는 과제를 수행하였고 실험 1과 마찬가지로 중간에 시각탐색을 수행하였고 실험 참가자들은 탐색자극을 찾아 빠르고 정확하게 반응해야 했다. 실험 결과, 실험 1과 2처럼 작업기억 내에서 정보를 계속해서 조작하고 있어야 하는 경우의 탐색 기울기는 단독으로 시각탐색과제를 수행할 때와 비교하여 유의미한 증가를 보였으며, 이는 작업기억 과정이 시각 탐색의 효율에 영향을 주는 것으로 해석된다. 특히, 이는 집행기능의 수행과 관련해 필요한 작업기억 용량이 시각탐색 수행에서도 요구되는 것으로 해석할 수 있다. Is executive working memory (WM) involved when searching for a visual target among distractors? In a recent study by Woodman et al (2001), the efficiencies of visual search were nearly identical for single-task (search-alone) and dual-task (memory & search) conditions. They suggested that visual search require minimal visual working memory resources, which is inconsistent with theories that propose a close link between attention and working memory. The manipulation of WM in their study, however, was confined to short-term memory stores. WM has been thought to include not only short-term memory stores but also executive processes that operate on the contents of memory (Baddeley & Hitch, 1974). The present study examined the involvement of WM in search using a dual-task paradigm in which participants performed visual search while manipulating, as well as maintaining, information held in WM. In Experiment 1, the participants were required to maintain and continuously subtract three from a three- digit number that was randomly renewed on each trial. Experiment 2 employed a different working memory task, in which participants were required to retain a sequence of letters and reorder the sequence into alphabetic order in memory. While they were performing these executive working memory tasks, the participants were asked to rapidly detect targets presented within visual search arrays. In both experiments, the search slopes in the dual-task condition were significantly steeper than those in the search-alone condition, indicating that performing the WM tasks influenced the efficiency of visual search. These results suggest that WM resources related to executive functions seem to be required in visual search.

Effects of Scaffolding Type and Working Memory on Programming Performance and Computational Thinking Skills in Elementary School Students’ Programming Learning

황이핀 전남대학교 2023 국내박사

Various studies have documented that scaffolding is sociocultural theory-driven assistance for improving learning outcomes. Cognitive and metacognitive scaffolding, however, have received scant attention in terms of their comparative effects on learners' programming development. On the other hand, learning programming involves working memory. As a partial attempt in this respect, the current study aimed to explore how cognitive and metacognitive scaffolding, alone or in combination, influence elementary school students’ programming performance and computational thinking skills while considering their working memory. For this purpose, this study employed a quasi-experimental pretest-posttest design with 173 fifth graders as participants. Four intact classes were randomly assigned to a control group and three experimental groups: cognitive scaffolding, metacognitive scaffolding, and both forms of scaffolding, namely, cognitive-and-metacognitive scaffolding. Before learning to program in Scratch, participants were required to complete a prior programming knowledge test, working memory tests, and a computational thinking test. After a seven-week programming learning activity, every participant was expected to finish a final project that served as an assessment of programming skills. Subsequently, participants were given post-tests of programming knowledge and computational thinking. Furthermore, students were classified as having low and high levels of working memory with regard to central executive working memory, phonological working memory, and visuo-spatial working memory. Data from a total of 168 students were analyzed due to some absences. Two-way MANCOVAs and ANCOVAs were implemented to investigate the two research questions. The following are the major findings of the study. First, scaffolding had a significantly superior effect on programming knowledge but not programming skills compared to non-scaffolding instruction. The cognitive-and-metacognitive scaffolding group did not show significantly better scores in programming knowledge and skills than the cognitive or metacognitive scaffolding group. Likewise, no significant difference was found between the metacognitive and cognitive scaffolding groups in programming knowledge and skills. Second, there was a significant difference between the experimental and control groups in computational thinking skills. However, students in the cognitive-and-metacognitive scaffolding group did not develop significantly greater computational thinking skills than those in the cognitive or metacognitive scaffolding group. Similarly, the metacognitive scaffolding group did not show significantly higher computational thinking skills than the cognitive scaffolding group. Third, the findings indicated that students with high capacities of working memory (central executive, phonological, and visual-spatial working memory) scored significantly higher on programming knowledge, programming skills, and computational thinking skills than low-capacity working memory students. Fourth, the interaction effects were only found between scaffolding type and central executive working memory on programming knowledge. For the students with low central executive working memory, there was a significant difference between the experimental and control groups. As for the students with high central executive working memory, the experimental groups significantly outperformed the control group. Moreover, high-capacity working memory students performed significantly better in the cognitive-and-metacognitive scaffolding group than in the cognitive or metacognitive scaffolding group. In addition, high-capacity working memory students also obtained significantly higher scores in the metacognitive scaffolding group than in the cognitive scaffolding group. This study provides implications for the design and development of scaffolding based on Vygotsky’s theory of cognitive and metacognitive mediation. In addition, more attention should be paid to individual differences in working memory during programming activities since working memory is greatly important for students’ success in programming performance and computational thinking skills. 그동안 많은 연구에서 학습성과 향상을 위한 사회문화이론의 보조 도구로의 스캐폴딩이 자주 언급되어 왔다. 그러나 학습자의 프로그래밍 성취를 위한 다양한 인지적 및 메타인지적 스캐폴딩을 비교한 연구는 부족한 실정이다. 한편, 작동기억은 프로그래밍 학습에서 중요한 역할을 하는 것으로 나타났다. 이와 관련하여 본 연구는 초등학생들의 작동기억을 고려하여 인지적 스캐폴딩과 메타인지적 스캐폴딩이 학생의 프로그래밍 성취도 및 컴퓨팅 사고력에 어떤 영향을 미치는지를 검증하였다. 연구대상은 중국 5 학년 학생 173 명이었다. 이 연구에서는 이질통제집단 사전-사후검사 설계를 활용하였다. 즉, 연구의 실험집단은 인지적 스캐폴딩, 메타인지적 스캐폴딩, 인지적 및 메타인지적 스캐폴딩 집단으로 구성되었고, 통제집단은 스캐폴딩을 제공받지 않았다. Scratch 프로그래밍 활동에 앞서 참가자들에게 사전 프로그래밍 지식, 작동기억, 컴퓨팅 사고력 등의 검사를 수행하도록 요청하였다. 7 주간의 프로그래밍 활동 후, 참가자들은 프로그래밍 기능의 평가로서 최종 프로젝트를 완성하였다. 이어 프로그래밍 지식 사후 검사, 컴퓨팅 사고력 검사를 실시하였다. 또한 학생들의 작동기억은 중앙집행 작동기억, 언어적 작동기억, 시공간적 작동기억 상에서 높은 집단과 낮은 집단으로 분류되었다. 173 명의 학생 중 최종 168 명의 학생들의 자료가 취합되었으며, 이를 분석하였다. 두 가지 연구 문제를 해결하기 위하여 이원 다변량공분산분석(MANCOVA)과 공분산분석(ANCOVA)를 실시하였다. 연구 결과는 다음과 같다. 첫째, 스캐폴딩을 제공받은 집단은 스캐폴딩을 제공받지 않은 집단보다 프로그래밍 지식이 유의하게 높은 것으로 나타났다. 그러나 실험집단과 통제집단간 프로그램 기능에는 유의한 차이가 없었다. 인지적 및 메타인지적 스캐폴딩을 동시 제공받은 집단이 인지적 스캐폴딩 집단이나 메타인지적 스캐폴딩 집단에 비해 프로그래밍 지식과 기능 상에서 유의하게 더 높은 점수를 보이지 않았다. 또한, 메타인지적 스캐폴딩 집단과 인지적 스캐폴딩 집단은 프로그래밍 지식과 기능에서도 유의한 차이가 없었다. 둘째, 컴퓨팅 사고력에는 실험집단과 통제집단 사이에 유의한 차이가 있었다. 그러나 인지적 및 메타인지적 스캐폴딩을 동시 제공받은 집단은 인지적 스캐폴딩 집단이나 메타인지적 스캐폴딩 집단보다 유의하게 높은 컴퓨팅 사고력을 보이지는 못 하였다. 또한 메타인지적 스캐폴딩 집단과 인지적 스캐폴딩 집단 사이에 컴퓨팅 사고력에는 유의한 차이가 없었다. 셋째, 작동기억이 높은 학생들은 작동기억이 낮은 학생들보다 프로그래밍 지식, 프로그래밍 기능, 컴퓨팅 사고력이 유의하게 높게 나타났다. 넷째, 프로그래밍 지식에 있어서 스캐폴딩 유형과 중앙집행 작동기억의 상호작용 효과가 있었다. 중앙집행 작동기억이 낮은 학생들의 경우 실험집단과 통제 집단 간에만 유의한 차이가 있었고, 중앙집행 작동기억이 높은 학생들의 경우도 동일한 결과를 보였다. 또한 중앙집행 작동기억이 높은 학생들은 인지적 및 메타인지적 스캐폴딩을 동시 제공받은 집단에서 인지적 스캐폴딩 집단이나 메타인지적 스캐폴딩 집단에서보다 프로그래밍 지식 점수가 유의하게 더 높았다. 또한 중앙집행 작동기억이 높은 학생들은 메타인지적 스캐폴딩 집단에서 인지적 스캐폴딩 집단에서보다 프로그래밍 지식 점수가 유의하게 더 높았다. 본 연구는 초등학생의 프로그래밍 학습을 위한 Vygotsky 의 인지적 및 메타인지적 중개이론에 입각한 스캐폴딩 설계 및 개발에 시사하는 바가 크다. 또한 작동기억은 학생들의 프로그래밍 성과와 컴퓨팅 사고력에서 중요한 요소 중 하나이므로 프로그래밍 활동 중 작동기억의 개인차에 더욱 유의할 필요가 있다.

Interactions between Visual Attention and Visual Working Memory during Visual Search : Evidence from Dual-Task Paradigm

오세환 연세대학교 2002 국내석사

시각적 주의와 시각적 작업기억은 서로 밀접한 관련을 가지는 것으로 여겨져 왔다. 그러나, 최근 Woodman, Vogel 그리고 Luck (2001)은 이중과제 패러다임을 사용하여, 주의를 필요로 하는 계열적 시각탐색 과정과 비공간적 정보를 작업기억 내에 유지하는 과정 사이에 간섭이 나타나지 않음을 보임으로써 이를 반박하였다. 실험 1에서는, 비공간적 정보 대신에 위치정보를 작업기억 내에 유지하는 공간적 작업기억 과제를 사용하여, 시각탐색 과정과 공간적 작업기억 내의 정보유지 과정 사이에 간섭이 나타나는지를 살펴보았다. 실험 결과, 부가적 공간정보를 작업기억 내에 유지하면서 시각탐색을 할 때, 시각탐색의 효율성은 낮아졌으며, 공간적인 정보의 기억 정확율 역시 감소하였다. 이러한 결과는 효율적인 시각탐색을 위해서 공간적 작업기억이 필수적임을 보여주는 것이다. 실험 2에서는, 이중과제 패러다임을 사용한 이전 연구들에서 시각탐색 과정과 비공간적인 작업기억 사이의 간섭이 나타나지 않은 이유를 알아보았다. 이전 연구들과 마찬가지로 특정한 모양의 목표자극을 찾는 전형적인 시각탐색 과제와 특정한 모양 없이 수직 축을 중심으로 좌우 대칭인 도형을 찾는 시각탐색 과제에서의 비공간적 작업기억 정보의 주의 유도 효과를 측정한 결과, 특정한 모양의 목표자극 없는 시각탐색 과제를 수행하는 동안에만 작업기억 내의 부가적 정보에 의한 주의 유도 효과가 나타났다. 이는 시각탐색에서의 목표자극처럼, 현재의 목표와 보다 깊은 관련이 있는 대상이 존재하지 않을 때에만 작업기억 내의 다른 부가적인 대상이 주의에 영향을 미칠 수 있음을 의미하는 것이다. 본 연구의 결과는 작업기억이 시각탐색에 중요한 역할을 하며, 그 역할은 시각탐색과제의 본질에 따라 다양할 수 있음을 시사한다. Many theories of attention and working memory have proposed that attention and working memory are closely related to each other. However, through using dual-task paradigm, Woodman, Vogel and Luck (2001) have demonstrated that the visual search process did not interfere with the maintenance of non-spatial information in working memory. In Experiment 1, participants performed a visual search task while maintaining spatial information in working memory in order to investigate whether spatial working memory load interferes with the visual search process. The spatial working memory load slowed the visual search process and the search process impaired the maintenance of spatial information in working memory, implying a close relationship between spatial working memory and visual search process. In Experiment 2, it was questioned why non-spatial working memory load did not interfere with visual search process in the previous studies. To investigate the possibility that the target object could override the effect of the other objects in the working memory, the guidance effect of non-spatial working memory was measured during a visual search task in which the target was defined as a vertically symmetric object without a specified shape. The significant guidance effect was found when the target was defined as a vertically symmetric object, but it was not found when the target was defined as a specific shape, implying that the object in working memory can influence visual search process in the absence of the object that is more relevant to the current goal. The current study suggests that visual working memory plays a significant role in visual search, and the role of working memory could vary depending on the nature of the visual search task.

The Neural Architecture of Working Memory: Anatomical and Functional Studies of Prefrontal Cortex

Miller, Jacob Adam University of California, Berkeley ProQuest Disser 2021 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

In the first chapter, I investigate the role of prefrontal cortex activity in working memory. Here, I am motivated by inconsistencies in the neural substrates for working memory across studies, species, and recording techniques. For instance, non-human primate electrophysiology research finds that prefrontal circuitry maintains working memory representations, while human neuroimaging suggests that working memory content is instead stored in sensory cortices. These seemingly incompatible accounts for working memory are often confounded by differences in the amount of task training and stimulus exposure across studies, suggesting that long-term learning may influence the role of prefrontal function in working memory maintenance. To answer these questions, we longitudinally trained and scanned participants on a working memory task with complex stimuli. Then, we used multivariate analyses of functional neuroimaging (fMRI) data to test how representational structures of working memory activity patterns in prefrontal cortex change across intensive learning. We show that human prefrontal cortex develops stimulus- selective working memory responses with learning, more akin to results from electrophysiology studies. This approach uses a unique training and analysis framework to establish novel evidence for long-term memory influences on working memory maintenance.In the second chapter, we investigate how working memory is constantly used to guide our moment to moment behaviors. This reliance on working memory can lead us to make mistakes, like saying aloud the wrong word in a conversation. Such "action slips" are common occurrences but especially pronounced in individuals with prefrontal lesions, who may often pour salt instead of sugar into one's coffee, or mistakenly type "pizza" in an immediate texting conversation when thinking about your upcoming lunch (Lhermitte et al. 1986). To study this interaction between working memory and ongoing behavior, I implemented a dual-task experiment in which directional words must be held in working memory while more immediate, but unrelated, motor movements are performed. We show that motor behaviors unrelated to current working memory information are still influenced by one's working memory content (Miller et al. 2020). We are currently testing these behaviors with predictions from cortico-striatal circuit models of working memory gating (e.g., O'Reilly and Frank, 2006) by using transcranial magnetic stimulation. By causally perturbing prefrontal functioning and cortico-striatal connectivity, can we alter when and how often working memory content influences our immediate actions?In the final chapter, I outline how investigating human-specific neuroanatomical structures in frontal cortex is critical for a wider investigation of human cognition. The prefrontal cortex is disproportionately expanded in the human brain even relative to other advanced primates, and some structures such as tertiary sulci, small folds in the cerebral cortex, are often human-specific. I use multi-modal neuroimaging data to investigate relationships between microstructural and functional properties in human prefrontal cortex. We show that careful identification of often overlooked individual-level anatomical features (such as tertiary sulci) serve as a bridge between the microanatomical and functional properties of prefrontal cortex (Miller et al. 2021). Identifying these structures has implications for both individual-level prefrontal functioning and broader mappings between prefrontal anatomy, functioning, and cognitive domains. We propose that such careful investigations of individual-level neuroanatomy will help to generate structural-functional relationships in areas of cortex previously thought to have little or no consistent links between individual-level structure and function (Miller et al. 2021).