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(1 - 20 of 20)
- Title
- The suasory effect of affective and cognitive messages : a test of conflicting hypotheses
- Creator
- Cameron, Kenzie Alynn
- Date
- 1998
- Collection
- Electronic Theses & Dissertations
- Title
- The role of mental simulation in causal decision making
- Creator
- Niedermeier, Keith E.
- Date
- 1999
- Collection
- Electronic Theses & Dissertations
- Title
- Exploration in task space : similarity effects on task switching
- Creator
- Arrington, Catherine M.
- Date
- 2002
- Collection
- Electronic Theses & Dissertations
- Title
- Neuropsychological malingering and cognitive load : disrupting deception on neuropsychological measures through cognitive overload
- Creator
- Alban, Adam D.
- Date
- 2002
- Collection
- Electronic Theses & Dissertations
- Title
- The relationship between cognitive flexibility, depression, and anxiety in older adults
- Creator
- Delano-Wood, Lisa Marie
- Date
- 2002
- Collection
- Electronic Theses & Dissertations
- Title
- The effects of psychological skills training on the cognitions and performance of high school softball players
- Creator
- Elliott, Jill
- Date
- 2003
- Collection
- Electronic Theses & Dissertations
- Title
- Rightly or for ill : the ethics of remembering and forgetting
- Creator
- Reiheld, Alison Nicole Crane
- Date
- 2010
- Collection
- Electronic Theses & Dissertations
- Title
- Word problem structure and its effect on the transfer of learning to solve algebra word problems
- Creator
- Chang, Kuo-Liang
- Date
- 2010
- Collection
- Electronic Theses & Dissertations
- Description
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A problem in learning to solve mathematics word problems students have been facing is to transfer the learned problem-solving knowledge from one story context to another story context. Some studies have provided evidence showing that structure facilitates transfer of learning to solve word problems. However, it is still under development for what algebra word problem structures students can recognize and what kinds of structures are effective for what kinds of algebra word problems regarding...
Show moreA problem in learning to solve mathematics word problems students have been facing is to transfer the learned problem-solving knowledge from one story context to another story context. Some studies have provided evidence showing that structure facilitates transfer of learning to solve word problems. However, it is still under development for what algebra word problem structures students can recognize and what kinds of structures are effective for what kinds of algebra word problems regarding transfer of learning. In this dissertation, I explored the following three questions: (1) "What are the structures that students can recognize in the domain of algebra word problem?" (2) "What are the difficulties students will encounter when trying to find structures of algebra word problems?" and (3) "Are particular structures helpful in teaching for transfer of learning to solve algebra word problems?" Sixty-one college students participated in a 2-hour controlled experiment and 10-minute one-to-one interview. The results showed several word problem structures students recognized or created, and multiple levels of difficulties students encountered when trying to structure algebra word problems. The results also showed that students who received structure-based instruction had better performance in some types of transfer of learning to solve algebra word problems.
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- Title
- Sensory attenuation of action effects due to predictive forward models : when does it transfer to observed actions
- Creator
- Dewey, John A.
- Date
- 2012
- Collection
- Electronic Theses & Dissertations
- Description
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The sensory consequences of intentional actions (action effects) are often judged to be less intense compared to identical but externally generated stimuli. This phenomenon is normally explained in terms of predictive forward models within the sensorimotor system which partially inhibit predictable sensory feedback. An unsettled question is whether merely observing another agent performing a predictable action may also trigger a forward model with attendant sensory attenuation, or...
Show moreThe sensory consequences of intentional actions (action effects) are often judged to be less intense compared to identical but externally generated stimuli. This phenomenon is normally explained in terms of predictive forward models within the sensorimotor system which partially inhibit predictable sensory feedback. An unsettled question is whether merely observing another agent performing a predictable action may also trigger a forward model with attendant sensory attenuation, or alternatively, if a self-generated motor signal is necessary. I conducted three experiments to investigate this question using a visual speed discrimination task. Participants judged which of two moving stimuli was faster. The first stimulus was initiated by the participant's own key press (Self), another person's key press (Other), or the computer program (Computer), and had a fixed speed. The second stimulus was always initiated by the computer and had a variable speed. The point of subjective equality (PSE) was compared for each condition. In Experiment 1 participants performed the task at their own pace. The Self condition was judged to be slower than the Other or Computer conditions, while the latter two did not differ. To control for the possibility that self-initiated movements were more temporally predictable and/or less attended than movements by other agents, in Experiment 2 the pace was controlled by go signals, and a green light followed every human or computer action to indicate that a movement was about to begin. Compared to Experiment 1, the PSE increased in all conditions, but the Self condition was still judged to be slowest and the Computer condition the fastest, while the Other condition was in between. In Experiment 3 the predictability of the action effects was manipulated independently from the agent who produced them, in order to investigate whether expectation similarly attenuates the intensity of Self and Computer-initiated action effects. Participants used two keys to initiate moves in two directions (left or right). In the Predictable group, the direction of the move matched the direction of the key press 80% of the time. In the Unpredictable group, the directions only matched 50% of the time. Self moves were only attenuated in the Predictable group. I conclude that sensory attenuation is influenced by a combination of private and shared or publicly available information, and that the influence of public information may be particularly tuned to biological agents. Furthermore action effects must be predictable to become attenuated.
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- Title
- Attention and working memory : disrupting feature binding in visual working memory
- Creator
- Hakun, Jonathan G.
- Date
- 2013
- Collection
- Electronic Theses & Dissertations
- Description
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In the current study we investigated disruption of working memory for multi-feature visual objects through a visual change detection paradigm modified with a distraction manipulation (termed the "Binding Distraction Task"). The paradigm included three processing stages (study, maintenance, and test) with a distraction event presented during maintenance. The judgment performed on each trial involved deciding whether a single two-feature test object (a colored shape) contained the same or...
Show moreIn the current study we investigated disruption of working memory for multi-feature visual objects through a visual change detection paradigm modified with a distraction manipulation (termed the "Binding Distraction Task"). The paradigm included three processing stages (study, maintenance, and test) with a distraction event presented during maintenance. The judgment performed on each trial involved deciding whether a single two-feature test object (a colored shape) contained the same or changed combination of shape and color as one of the study objects (i.e. contained the same feature binding). The distraction event involved presenting an array of visual objects arranged spatially in a manner similar to the study array. We compared performance on trials where distraction arrays contained objects sharing feature-overlap with the current trial's study objects (matched arrays) with trials where distracter objects contained study-related features but no overlap with the current trial's study set (related arrays). As compared with trials involving empty distraction arrays and baseline performance (no distraction), the presentation of matched arrays was consistently disruptive of binding change detection performance across all of the experiments presented here. The performance cost associated with related arrays however was more variable across experiments. Through an individual differences approach, we investigated an executive gating account of the distraction effect. That is, disruption is caused by a failure to keep distracter objects from reaching visual working memory (VWM) thereby displacing study objects. Based on this account we predicted that individuals with high working memory capacity (WMC), as measured through complex span and single feature change detection task performance, should be more resistant to distraction than low WMC individuals. However, the results of our individual differences analysis failed to provide support for the executive gating hypothesis (costs were unrelated to WMC). Alternatively, we proposed that distraction costs may reflect a special case of contingent attention capture. That is, attention may be biased toward distracter objects that overlap with the features active in VWM. To explore this hypothesis further we additionally conducted an fMRI study. The results of our fMRI analysis indicated that regions of the brain that are commonly involved in the voluntary and stimulus-driven control of attention responded in a manner consistent with our contingent capture hypothesis. Regions involved in the voluntary control of attention (superior parietal and prefrontal) parametrically scaled in activation in accordance with the proposed demands associated with each distraction condition. However, as further evidence against the executive gating hypothesis, activation in all of the regions involved in voluntary control did not relate to performance costs. On the other hand, regions associated with the contingent capture of attention (specifically, the right ventrolateral prefrontal cortex, VLPFC, and temporo-parietal junction) only reliably responded to the filled distracter arrays (related and matched arrays). Further, activation within the right VLPFC was positively related to the performance cost observed in both conditions. Altogether the results of the current study support a stimulus-driven account of disruption of VWM for bound features. Specifically, we conclude that maintaining multiple bound representations in VWM creates a context in which distracter objects containing feature-overlap capture attention and result in the downstream impoverishment of stored representations.
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- Title
- The effects of expressive writing on neural markers of cognitive processing in worriers
- Creator
- Schroder, Hans (Hans S.)
- Date
- 2014
- Collection
- Electronic Theses & Dissertations
- Description
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Individuals with excessive anxiety and worry often require additional effort to complete tasks, rendering their performance inefficient. Inefficient information processing in anxiety is evident by enlarged amplitude of the error-related negativity (ERN), an event-related brain potential (ERP) elicited after errors during simple reaction time tasks. Although enlarged ERN among worriers is well documented, few studies have examined the effects of interventions aimed at reducing it. Thus, it is...
Show moreIndividuals with excessive anxiety and worry often require additional effort to complete tasks, rendering their performance inefficient. Inefficient information processing in anxiety is evident by enlarged amplitude of the error-related negativity (ERN), an event-related brain potential (ERP) elicited after errors during simple reaction time tasks. Although enlarged ERN among worriers is well documented, few studies have examined the effects of interventions aimed at reducing it. Thus, it is unknown whether the ERN could be used to gauge anxiety treatment effects on information processing. The current study aimed to address this gap by recording ERPs among worried undergraduates following an expressive writing exercise (n=18) or a control writing condition (n=16). Expressive writing entails writing about one's deepest thoughts and feelings about a particular event, which can free up cognitive resources and promote more efficient performance among anxious individuals. I predicted that by off-loading worries and freeing up resources, worried individuals in the expressive writing condition would demonstrate reduced ERN and equivalent performance compared to those in the control condition, indicative of more efficient performance. Results supported these predictions. Moreover, a related ERP reflective of conflict-related cognitive control (N2) was also reduced in the expressive writing condition. These results suggest that error- and conflict- related brain activity during simple tasks may be promising markers of treatment response among individuals with clinical anxiety.
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- Title
- The effects of primacy on rater cognition : an eye-tracking study
- Creator
- Ballard, Laura
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
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"Rater scoring has an impact on writing test reliability and validity. Thus, there has been a continued call for researchers to investigate issues related to rating (Crusan, 2015). In the current study, I answer the call for continued research on rating processes by investigating rater cognition in the context of rubric use in writing assessment. This type of research is especially important for rater training and rubric development because, despite efforts to guide raters to a common...
Show more"Rater scoring has an impact on writing test reliability and validity. Thus, there has been a continued call for researchers to investigate issues related to rating (Crusan, 2015). In the current study, I answer the call for continued research on rating processes by investigating rater cognition in the context of rubric use in writing assessment. This type of research is especially important for rater training and rubric development because, despite efforts to guide raters to a common understanding of the rubric criteria and to help raters converge on a common understanding of scoring bands, variance in rater scoring and rater behavior persists. Researchers have shown that trained raters do not always use rubric criteria in consistent ways, nor do they consistently use the same processes to score samples. This is relevant for the design of and use of scores from analytic rubrics, as raters are expected to allocate equal attention to each criterion within an analytic rubric, and non-equal attention has been shown to coincide with category reliability (Winke & Lim, 2015), and, therefore, overall test reliability. One factor which has not been investigated in assessment research is the role of information-primacy in rater cognition. Thus, in this study, I investigate the primacy effect in relation to rater-rubric interactions. Specifically, I investigate 1) whether the position of a category affects raters' assignment of importance to the category; 2) whether the position of a category affects raters' memory of a category; 3) whether raters pay more or less attention to a rubric category depending on its position in the rubric; 4) whether the position of the category affects the inter-rater reliability of a category; and 5) whether the position of a category affects the scores that raters assign to the category. I employed a mixed-methods within-subjects design, which included eye-tracking methodology. Thirty-one novice raters were randomly assigned to two groups and were trained on two rubrics in two phases. The rubrics were a standard rubric (from Polio, 2013) and a reordered rubric (identical to the standard rubric, except with categories appearing in a mirrored order to the reordered rubric). In round 1, raters trained on one of the two rubrics and rated the same 20 essays using the rubric. The second round took place five weeks after the completion of the first. In round 2, raters trained on the alternate rubric and re-rated the same 20 essays. I utilized several data-collection tools to investigate rater's cognition and behavior related to their rubric of training. I examined raters' beliefs about category importance, raters' recall of the descriptors in each rubric category, raters' focus on the rubric criteria during essay rating, and raters' scoring consistency and severity for each rubric category. Results show that as novice raters train on a new rubric and assign scores using the individual categories on the rubric, the raters' behavior pertaining to the outer-most positions (e.g., left-most and right-most) was most susceptible to ordering effects. That is, the findings show that the category position affected the raters' beliefs about what criteria are the most and least important when scoring an essay, how many descriptors raters were able to recall from a category, how much attention raters paid to a category on the rubric while rating, and how severely raters scored a given category. Additionally, the findings provided evidence that there was an interplay between the category type and category positions, resulting in either more pronounced primacy effects or leveling effects for individual rubric categories. Based on these findings, I discuss rater training, rubric design, and test-construct considerations for rubric designers and test developers."--Pages ii-iii.
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- Title
- The bridge : linking mood induction, self-report, and psychophysiology to vocabulary learning on a paired-associates learning task
- Creator
- Fox, Jessica Kate
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
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"Researchers in the field of second language acquisition continue to establish links between cognition and emotion (Dewaele, 2013; MacIntyre, 2002; MacIntyre & Gardner, 1989, 1991b, 1994; Segalowitz & Trofimovich, 2011). The purpose of the present study is to investigate to what extent physiological and self-report measures predict vocabulary language learning. This present study is inspired by hot cognition, cognitive processing influenced by emotions (Brand, 1987; Pekrun, 2006; Wolfe, 2006)...
Show more"Researchers in the field of second language acquisition continue to establish links between cognition and emotion (Dewaele, 2013; MacIntyre, 2002; MacIntyre & Gardner, 1989, 1991b, 1994; Segalowitz & Trofimovich, 2011). The purpose of the present study is to investigate to what extent physiological and self-report measures predict vocabulary language learning. This present study is inspired by hot cognition, cognitive processing influenced by emotions (Brand, 1987; Pekrun, 2006; Wolfe, 2006). Two groups of thirty-five adult language learners were placed in a negative experimental group or a neutral comparison group and exposed to a series of mood-inducing video-only film clips (Carvalho, Leite, Galdo-Álvarez, & Gonçalves, 2012) after which they learned the forms and meanings of 24 Indonesian concrete nouns. Participant physiological response measures (heart rate, heart rate variability, and skin conductance levels) were collected during baseline and film-viewing periods; additional data collected included periodic emotional self-reports, performance on immediate vocabulary-learning posttests, and a battery of anxiety questionnaires. Findings revealed that changes in heart rate and skin conductance levels influenced performance on the paired-associates vocabulary-learning task. Additionally, the skin conductance measure predicted vocabulary learning when the effects of mood induction and all other known individual differences were controlled for."--Page ii.
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- Title
- Automaticity as a hidden cost of expertise : situational and individual-difference factors underpinning errors of automaticity
- Creator
- Burgoyne, Alexander P.
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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A traditional view of automaticity holds that the ability to perform well-practiced skills without attention is adaptive because it frees mental resources to process other information. Without denying the benefits of automaticity, I show how it can also lead to error in domains of expertise such as driving, medical diagnosis, problem solving, and reading. I begin by discussing automaticity within the context of two theoretical frameworks, classical theories of skill acquisition and dual...
Show moreA traditional view of automaticity holds that the ability to perform well-practiced skills without attention is adaptive because it frees mental resources to process other information. Without denying the benefits of automaticity, I show how it can also lead to error in domains of expertise such as driving, medical diagnosis, problem solving, and reading. I begin by discussing automaticity within the context of two theoretical frameworks, classical theories of skill acquisition and dual process theory. I then examine situational and individual-difference factors that make errors of automaticity more likely to occur. Next, using proofreading as a testbed, I demonstrate how knowledge, expectations, and other top-down constraints influence reading behaviors and comprehension. I then present two experiments to investigate the self-generation effect in proofreading: the hypothesis that it is more difficult to detect mistakes in one's own writing than in the writing of others. The reasoning behind this hypothesis is that overfamiliarity with self-generated text increases the probability that errors are overlooked or seen but undetected. Finally, I discuss implications of the research and argue that understanding the benefits and consequences of automaticity is critical to improve decision-making outcomes across a wide range of applied contexts.
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- Title
- RHYTHM PERCEPTION AND NEURAL ACTIVATION DIFFERENCES BETWEEN ADULTS WHO DO AND DO NOT STUTTER
- Creator
- Wieland, Elizabeth Ann
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Stuttering is a communicative disorder that involves disruptions to fluent speech, which are characterized by frequent repetition or prolongation of syllables or words, and/or by frequent hesitations or pauses. Prior research has identified a number of hallmarks and deficits associated with stuttering, including generalized timing deficits, and reduced functional connectivity in the rhythm network previously identified to be involved in the perception of musical meter. Building on assumptions...
Show moreStuttering is a communicative disorder that involves disruptions to fluent speech, which are characterized by frequent repetition or prolongation of syllables or words, and/or by frequent hesitations or pauses. Prior research has identified a number of hallmarks and deficits associated with stuttering, including generalized timing deficits, and reduced functional connectivity in the rhythm network previously identified to be involved in the perception of musical meter. Building on assumptions of (1) shared neurocognitive resources exist for metrical structure-building for perception and production of auditory patterns in both music and language, and (2) functional similarity exists in processes involved in predictive action-preparation from metrical structure in auditory information, it was predicted that a core deficit in stuttering involves deficiencies in integrating candidate metrical structures with sensory evidence that would support them. To test this prediction, an experiment was designed using a same/different rhythm discrimination task. Critically, half the stimuli provided greater support for the induction of a beat/meter (“simple rhythms”), whereas the other half were matched in interval types but provided less signal-based statistical support for the induction of a beat/meter (“complex rhythms”). Participants were 36 adults who do and do not stutter, and the rhythm discrimination task was done while undergoing functional magnetic resonance imaging. For the behavioral results, statistical analyses using analysis of variance/covariance did not show any significant effects or interactions; however, a linear mixed effects model which accounted for multiple sources of variance revealed poorer performance on complex rhythm discrimination by adults who stutter compared with those that do not stutter. For the neural results, activation in the core rhythm network during the rhythm discrimination task was observed for both groups (bilateral insula, bilateral STG, bilateral SMA, and bilateral premotor area) for both simple and complex rhythms. However, adults who stutter additionally showed activation in the bilateral putamen and bilateral IFG, suggesting that one or both of these areas may perform a compensatory function in rhythm perception and predictive action-preparation. These results can be interpreted with respect to predictive coding processes in the brain supporting perception, action, and cognition, as well as recent conceptual extensions to auditory processing of music, language, and speech, which propose that linguistic perception and production are “two sides of the same coin.” Specifically, it is proposed that listeners attempt to build top-down metrical representations for structured auditory sequences, and during language processing, these top-down metrical representations must be merged with representations of other structures in language to give rise to a coherent overall linguistic representation. It is proposed that a core deficit in stuttering involves deficient processes for integration of top-down metrical/prosodic structure and/or bottom-up sensory indices of dynamic sensorimotor states, toward construction of a coherent overall linguistic representation. Evidence for this proposal comes from findings that: (1) distal context rate and rhythm cues in speech influence metrical/prosodic structures heard across identical acoustic material, thereby influencing goodness-of-fit evaluations of alternative top-down candidate representations of lexico-syntax; (2) a hallmark of stuttering is anomalous white matter connectivity and reduced functional organization of rhythm networks in the brain. This study is the first to investigate non-speech rhythm perception in adults who stutter, and the findings suggest new hypotheses regarding how dynamic connections among brain structures (e.g., basal ganglia, STG) instantiate computations toward the imputation of timing and meter from acoustically variable auditory signals.
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- Title
- Syntactic analysis and the acquisition of vietnamese pluralizers
- Creator
- Le, Ni-La
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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This dissertation focuses on the interaction between definiteness and number in Vietnamese noun phrases, as reflected through the behavior and interpretation of the two pluralizers cac and nh1EEFng. First, I propose a unified structure for Vietnamese noun phrases in which cac/nh1EEFng are quantifier-like and occupy a Quantity head. Their distributional properties are accounted for by competition between heads (cac/nh1EEFng compete with Nums and most Qs on the Quantity head which is higher...
Show moreThis dissertation focuses on the interaction between definiteness and number in Vietnamese noun phrases, as reflected through the behavior and interpretation of the two pluralizers cac and nh1EEFng. First, I propose a unified structure for Vietnamese noun phrases in which cac/nh1EEFng are quantifier-like and occupy a Quantity head. Their distributional properties are accounted for by competition between heads (cac/nh1EEFng compete with Nums and most Qs on the Quantity head which is higher than the CL head) and by their c-selection (nh1EEFng requires restriction on the noun phrase because it semantically signals a partitive relation and thus selects for a CP, while cac, like Nums and other Qs, takes a ClP as complement). Meanwhile, their interpretations are accounted for by the properties of the complements they take and the feature content of each head. Second, I report the results from three experiments on the comprehension of singular and plural definite noun phrases by Vietnamese children ages 3 to 7, as well as adults. Contra results from English and Spanish, Vietnamese children in Experiment 1 and 2 make few definiteness errors, instead struggling with number, casting doubt on a universal difficulty with definiteness. In particular, during an act-out task, children acquiring languages with definite determiners and grammatical number (English, Spanish) sacrifice definiteness in favor of number, while those acquiring languages like Vietnamese prioritize definiteness, resulting in number errors. However, Experiment 3 uses a picture selection task showing that Vietnamese-speaking children do have number knowledge, specifically knowledge of the plurality of cac/nh1EEFng, and that they prioritize number over definiteness in this specific design. I argue that crosslinguistic differences in the acquisition of number and definiteness arise from how children integrate information from number and definiteness, which is task-dependent and language-specific.
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- Title
- The Timing of Misinformation Matters : Sleep both increases memory distortion and protects against it
- Creator
- Day, Alison J.
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Prior work investigating the effect of sleep on false memory using the Deese-Roediger-McDermott paradigm has yielded equivocal results. Here, we sought to clarify the effect of sleep on false memory using the misinformation paradigm. Participants watched a film of a mock robbery, were given post-event misinformation about the film, and completed a recognition test after a 12-hour retention interval that consisted of waking activity or sleep. We manipulated when participants received...
Show morePrior work investigating the effect of sleep on false memory using the Deese-Roediger-McDermott paradigm has yielded equivocal results. Here, we sought to clarify the effect of sleep on false memory using the misinformation paradigm. Participants watched a film of a mock robbery, were given post-event misinformation about the film, and completed a recognition test after a 12-hour retention interval that consisted of waking activity or sleep. We manipulated when participants received misinformation; half received misinformation after watching the film and before the retention interval and half received misinformation after the retention interval, before the test. Thus, for participants who slept, half received misinformation prior to sleep and half received it after a sleep period. Most interesting, we found an interaction between sleep condition and timing of misinformation. In the sleep group, participants who received misinformation before the retention interval showed higher false memory than those who received misinformation after the retention interval. Timing of misinformation did not affect false memory in the wake condition. These results suggest that consolidation processes can have opposite effects on false memory. If conflicting information is presented after sleep, consolidation protects memory from distortion possibly by mitigating interference effects. However, the same consolidation processes may increase distortion if conflicting information is presented prior to sleep possibly by integrating related memories that are available at the time of sleep (i.e. the true event and the conflicting information). This work has implications for theories of memory and applied implications for the criminal justice system.
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- Title
- EXPLORING THE EFFECT OF RELATIVE TIMING OF TARGET AND BACKGROUND WORDS ON SPEECH UNDERSTANDING WITH AND WITHOUT A BACKGROUND RHYTHMIC CONTEXT
- Creator
- Smith, Toni Marie
- Date
- 2021
- Collection
- Electronic Theses & Dissertations
- Description
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Using the Coordinate Response Measure (CRM) paradigm, recognition of target speech in the presence of competing speech has been shown to depend upon both the rhythmic context of target and background speech and fundamental frequency differences between the target and background speakers (McAuley et al., 2021). In the present study, two experiments examined the effects of the relative timing of target and background key words and the presence or absence of a background rhythmic context on...
Show moreUsing the Coordinate Response Measure (CRM) paradigm, recognition of target speech in the presence of competing speech has been shown to depend upon both the rhythmic context of target and background speech and fundamental frequency differences between the target and background speakers (McAuley et al., 2021). In the present study, two experiments examined the effects of the relative timing of target and background key words and the presence or absence of a background rhythmic context on target key word recognition using the same male talker for both target and background sentences. Experiment 1 varied the onset asynchrony between target and background key words when background rhythmic context was removed (i.e., the background consisted only of the competing key words) and Experiment 2 manipulated the rhythm of background speech leading up to key words, but left the key words intact with an onset asynchrony of ±50ms. Experiment 1 revealed an asymmetric U-shaped performance curve where (1) target recognition improved with increasing deviation of background key words from the expected onset timing of target keywords, and (2) target key words were better recognized when they began prior to the onset of background key words, compared to when they began after. With the reintroduction of the background context in Experiment 2, performance was reduced to chance both when the background rhythm was intact and when it was altered to be rhythmically irregular, suggesting that listeners were unable to distinguish target and background sentences and could not develop expectations for target key word timing
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- Title
- DECODING NEURAL MECHANISMS OF SURROUND SUPPRESSION IN FEATURE-BASED ATTENTION
- Creator
- Fang, Wanghaoming
- Date
- 2021
- Collection
- Electronic Theses & Dissertations
- Description
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Feature-based attention (FBA) selectively enhances processing of an attended feature at the expense of unattended or task-irrelevant features. Recent studies showed that FBA modulates the perceptual space with both a monotonic profile (i.e., feature-similarity gain) and a non-monotonic profile (i.e., surround suppression). A significant question arises regarding the neural mechanism of the non-monotonic surround suppression effect. Previous studies have suggested that two candidate neuronal...
Show moreFeature-based attention (FBA) selectively enhances processing of an attended feature at the expense of unattended or task-irrelevant features. Recent studies showed that FBA modulates the perceptual space with both a monotonic profile (i.e., feature-similarity gain) and a non-monotonic profile (i.e., surround suppression). A significant question arises regarding the neural mechanism of the non-monotonic surround suppression effect. Previous studies have suggested that two candidate neuronal mechanisms could underlie these attentional modulations: a shift of neuronal tuning preference toward the attended feature, or a multiplicative gain modulation that scales the overall responses without changing their tuning property. Yet the empirical evidence for these mechanisms is still lacking. In the current work, we explored how these neuronal mechanism manifest at the level of fMRI BOLD measurement using a simulation approach. Specifically, we employed an encoding/decoding approach by first simulating voxel responses from neuronal population assuming either mechanism and then applying a regression-based inverted encoding model (IEM) and a Bayesian method to decode population representations. We found that both methods captured the signature patterns associated with these different neuronal mechanisms. In our second aim, we systematically varied the correlation structure of voxel noise to further compare these different multivariate methods in a stimulus classification task. Our results showed a clear advantage of the Bayesian method over IEM, suggesting that the Bayesian method was superior for deciphering neural representation given the prevalent noise correlation and variable tuning width in the brain. In sum, our current simulation work may provide a proof of concept for future empirical studies investigating cortical mechanism of FBA using non-invasive methods, as well as guidance for choosing suitable methods in these investigations.
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- Title
- Competition in natural language meaning : The case of adjective constructions in Mandarin Chinese and beyond
- Creator
- Cong, Yan
- Date
- 2021
- Collection
- Electronic Theses & Dissertations
- Description
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Utterances compete with each other. Rational speakers choose an utterance that is true, informative, and relevant, and listeners reason about that choice. As a consequence, pragmatic listeners make inferences about other possible utterances (so-called alternatives). In the well-studied case of Scalar Implicature (henceforth SI), pragmatic enrichment yields the inference that more informative alternatives are false, or at least that the speaker doesn’t believe them. A central question in the...
Show moreUtterances compete with each other. Rational speakers choose an utterance that is true, informative, and relevant, and listeners reason about that choice. As a consequence, pragmatic listeners make inferences about other possible utterances (so-called alternatives). In the well-studied case of Scalar Implicature (henceforth SI), pragmatic enrichment yields the inference that more informative alternatives are false, or at least that the speaker doesn’t believe them. A central question in the SI literature is what counts as an alternative of a given utterance, due to what is known as the symmetry problem: without constraints on alternatives, every potential alternative ? has a symmetric partner (roughly, not ?), whose existence preempts any SI about ?. Consequently, theories of formal alternatives have been proposed (Katzir, 2007). However, relatively few studies concern Non-Scalar Implicature (henceforth NSI) (Rett, 2015). This dissertation argues that the interpretation of adjectival constructions in Mandarin Chinese involves non-scalar competition, that a kind of symmetry problem arises even for NSIs, and that standard (e.g., Katzirian) theories of formal alternatives do not solve the problem. I propose to associate gradient costs with structural alternatives to break symmetry.
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