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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Binary rocs and their implications for the measurement of memory

Dube, Chad M 01 January 2011 (has links)
Bröder and Schütz (2009) have argued that the curvature typically observed in recognition memory receiver-operating characteristics (ROCs) is a by-product of the ratings task often used to obtain them. According to those authors, ROCs collected by experimentally manipulating response bias are linear and consistent with the assumptions of threshold and multinomial processing tree (MPT) models. Two experiments are reported which are broadly consistent with previous work by Dube and Rotello (under review) in showing that ROCs are curved and consistent with signal detection theory (SDT) regardless of the procedure used to obtain them. These results have implications for how accuracy is measured in tasks requiring binary responses. It is suggested that the use of statistics consistent with the assumptions of threshold models (e.g. percent correct, hits minus false alarms) should be avoided, as they are likely to produce statistical errors in several areas of the literature where ROCs have been found to be curved (Rotello, Masson, & Verde, 2008; Dube, Rotello, & Heit, 2010; 2011). SDT-based measures and ROC analysis are recommended to complement or replace analyses based on threshold statistics.
212

Attention to television in preschoolers who exhibit ADHD symptoms: An ERP investigation

Demers, Lindsay B 01 January 2011 (has links)
Children with ADHD suffer from low and high order attention deficits. Work by E.P. Lorch and colleagues shows that these attention deficits affect televised narrative comprehension. The purpose of this research was to determine the extent to which the televised narrative comprehension deficits are the result of an inability to inhibit processing of irrelevant information. To achieve this, data were collected from 16 healthy adults and 37 preschool age children who varied in their ADHD symptoms. Participants were instructed to attend to one of two simultaneously presented audio tracks from children’s television shows. For all participants the video that matched the target audio track was presented on a screen in front of them. Throughout viewing, white noise probes were played from the same locations as the attended and unattended audio tracks. Each participant sat through two different televised narratives. Narrative comprehensibility was manipulated within-subject such that each participant saw one comprehensible narrative and one incomprehensible narrative. Throughout both, EEG was recorded and subsequently time-locked to the presentation of the auditory probes from the attended and unattended locations. After each narrative, participants were asked to recall aspects of the story that were either central or peripheral to the causal chain of events. The morphology of the participants’ auditory evoked potentials followed the expected pattern (a positivenegative- positive complex for adults and a broad positivity for children during the 300ms after stimulus onset). All participants showed greater processing of the probes from the attended location during the incomprehensible narrative than during the comprehensible narrative, which suggests that participants were processing more information from the attended location when the sequence of events in the narrative was unpredictable. Only children with relatively higher levels of ADHD symptoms showed processing of the probes during the comprehensible narrative. This pattern of results suggests that children with ADHD symptoms were as capable as the typically developing children and adults at the spatially selective attention task, but that they had difficulty engaging in selective attention within the target channel. Contrary to our hypotheses, the amount and type of information recollected did not differ by ADHD status.
213

SAC attack: Assessing the role of recollection in the mirror effect

Pazzaglia, Angela M 01 January 2012 (has links)
Low-frequency (LF) words have higher hit rates (HRs) and lower false alarm rates (FARs) than high-frequency (HF) words in recognition memory, a phenomenon termed the mirror effect by Glanzer and Adams (1985). The primary mechanism for producing the mirror effect varies substantially across models of recognition memory, with some models localizing the effects during encoding and others during retrieval. The current experiments contrast two retrieval-stage models, the Source of Activation Confusion (SAC; Reder, Nhouyvanisvong, Schunn, Ayers, Angstadt, & Hiraki, 2000) model and the unequal variance signal detection theory (UVSDT) criterion shift model (e.g., DeCarlo, 2002). The SAC model proposes that two distinct processes underlie the HR and FAR effects, with a familiarity process driving the FAR effect and a recollective process driving the HR effect. The UVSDT criterion shift model assumes that subjects use different criteria when making recognition judgments for HF and LF words, with this single process driving both the HR and FAR effects. Experiment 1 incorporated divided attention and speeded responding manipulations designed to remove the contribution of recollection in the SAC model, thereby eliminating the LF HR advantage. Experiment 2 manipulated the salience of the frequency classes, as the UVSDT criterion shift model requires that subjects are aware of the distinct frequency classes in order to shift their criteria. Across both experiments, model simulations and direct fits of the SAC model demonstrated systematic errors in prediction. While the UVSDT model struggled in fits to Experiment 1 data, the model provided acceptable fits to Experiment 2 data and accurately predicted the general pattern of effects in all cases. Furthermore, state-trace analyses provided compelling evidence in favor of single-process rather than dual-process models of recognition memory, casting serious doubt on the validity of the dual-process SAC model. Finally, the current experiments highlight the importance of obtaining model-based estimates of sensitivity and bias across frequency classes, as the standard practice of conducting direct comparisons of HRs and FARs for HF and LF words confounds bias and sensitivity differences.
214

A reconstructive theory of serial-order memory

Reichle, Erik Daniel 01 January 1997 (has links)
Theories of serial-order memory either include specialized mechanisms to represent order or claim that sequences of events are represented in memory by structures that are constructed during encoding. Unfortunately, both approaches have many shortcomings, and neither can explain how the order of arbitrary event sequences (i.e., sequences that are not intentionally learned; e.g., trips to the grocery store) are remembered. This paper presents an alternative approach to serial-order memory, one in which order is not directly represented in memory but is instead reconstructed during retrieval. This reconstructive theory is presented in two parts. The first demonstrates how the components of episodic memory (as implemented in the Search of Associative Memory model of Raaijmakers & Shiffrin's, 1981b) that are necessary to encode, represent, and retrieve information about events in memory are sufficient to account for key aspects of serial-order memory. Several emergent properties of the reconstructive model allow it to explain phenomena that have been problematic for other theories of serial-order memory (e.g., recency effects). The second part of this paper focuses on how contextual information is used to reconstruct memory for order. Four experiments that examine the role of context in serial-order memory are presented. Experiment 1 evaluated three assumptions of the Raaijmakers and Shiffrin (1981b) model; the results support the model and indicate that people (1) attend to and remember the contexts in which items are presented, (2) represent contextual changes in memory, and (3) are better at remembering the contexts of items near the beginnings of sequences and following changes in context. Experiment 2 extends these results by showing that people use contextual information to make judgments about the relative order of two items. Experiment 3 replicates this result using a slightly different paradigm. Finally, Experiment 4 attempted to find out whether or not people use the most general contextual information available to make order judgments. The results of Experiment 4 are less conclusive than those of Experiments 1-3; several sources of this discrepancy are discussed.
215

Antecedents and distractors in the anaphor resolution process: The influence of relative strength of association in memory

Mason, Robert Allen 01 January 1998 (has links)
In three experiments, subjects read passages containing one or two candidates for an anaphoric reference that differed in their distance from the reference and their strength of association to the categorical anaphor. Eye movements were recorded in Experiment 1. When a distractor was present, readers spent longer on the anaphoric noun when the antecedent was high-typical; however, they spent longer on the words following the anaphoric noun when the antecedent was low-typical. This effect, accompanied by an increase in regressions to the disambiguating adjective for the target region when the antecedent was low-typical and a distractor was present, indicate that, in this condition, the distractor was identified before the antecedent. Recognition probes in Experiment 2 showed that near, high-typical distractors were more available than far, low-typical antecedents; however, a facilitation effect for the antecedents suggest that the anaphor was successfully resolved. Delayed long-term memory probes were used in Experiment 3 to investigate the result of the resolution process. The results from the three experiments are discussed in terms of a general framework for anaphor resolution.
216

Eye movements during recognition of a rotated scene

Nakatani, Chie 01 January 2001 (has links)
Eye movements during a scene rotation task were measured in two experiments. Two desktop scenes (each consisting of three office objects on a square desktop) were presented consecutively. Participants judged the identity of the two scenes. On same trials, the two scenes were either identical or one was a rotated version of the other. On different trials, the scene frame was as on the same trials, but either the locations or the orientations of some of the objects were changed. Eye movement measures were obtained as real-time indices of information processing. During the task, the eyes dwell on an object region longer when a scene was rotated further (i.e. gaze duration increased) only after the first 900ms of scanning. This result accords to a model in which (a) initial encoding takes place before an alignment process is initiated and (b) alignment is piecemeal and takes place on a gaze-by-gaze basis. As in previous scene rotation experiments, the slope of a mental rotation function differed between conditions. Response latencies increased more strongly with rotation angle in the orientation-change condition than in the location-change condition. This difference was mainly observed for gaze duration. On the other hand, response times in the Y (vertical)-axis rotation conditions were longer than those in the X (horizontal)- and Z (line-of-sight)-axis rotation conditions. This difference corresponds to an increase in the number (rather than the duration) of gazes in the Y-axis rotation conditions. Furthermore, when objects switched their locations, the changed object was fixated earlier than an unchanged object. In accordance with this result, it was assumed that the detection of the location-change is handled not only by foveal vision, but also by parafoveal vision. In Experiment: 2, the desktop was removed from the scene in half of the conditions. In these conditions location-changed objects no longer were fixated earlier than unchanged objects. Another consequence of removing the desktop was that the eyes need to visit objects more often. This means that desktop frame facilitates the piecemeal alignment process. The results were discussed in terms of viewpoint-dependent models of object recognition.
217

Investigating Semantic Competition Between Global Knowledge and Local Context in Real-Time Sentence Processing

Unknown Date (has links)
Extensive evidence shows that listeners use global knowledge to generate predictions of upcoming sentences themes; however, there is less investigation on how local context that semantically conflicts with long-standing global knowledge is integrated and applied in real-time sentence comprehension. Three studies used the visual world paradigm to study this question. Experiment 1 replicated previous findings that listeners typically rely on global knowledge to anticipate sentence themes. Experiment 2 suggests that adult listeners rapidly increase the weight of combinatorial evidence from local context and decrease the weight of global knowledge to anticipate the appropriate sentence theme. Experiment 3 shows that 5-8 year-old children do not overcome semantic conflict in time to generate predictions of the sentence theme. These results indicate that in the presence of semantic conflict, adult comprehenders rapidly learned to favor local context over global knowledge, but this ability appears to emerge after a child turns 8 years-old. / A Thesis submitted to the Department of Psychology in partial fulfillment of the Master of Science. / Fall Semester 2016. / November 14, 2016. / Includes bibliographical references. / Michael Kaschak, Professor Co-Directing Thesis; Arielle Borovsky, Professor Co-Directing Thesis; Colleen Kelley, Committee Member.
218

Examination of the Mechanisms Driving Long-Range Prime-to-Target Structural Priming

Unknown Date (has links)
Bock and Griffin (2000) presented two experiments demonstrating that structural priming (i.e., increased likelihood of producing a given syntactic form if you have just produced that form in another utterance) can be long-lasting. In their experiments, participants alternated between reading sentences aloud (where they read prime sentences aloud) and describing pictures (where the target pictures gave participants the opportunity to produce the same syntactic structure as was used for the prime sentence). The likelihood of describing the target picture with the same structure as the prime sentence was shown to be equally strong when the prime and target were presented in immediate succession (Lag 0) and when they were separated by up to 10 intervening filler sentences (Lag 10). This result has been taken as evidence for the claim that structural priming is the result of implicit learning within the language production system. The current project is aimed at taking a closer look at the factors that affect the persistence of structural priming across numerous filler items. Overall, our data provided mixed support for Bock and Griffin's (2000) claims. Although we found a robust priming effect at adjacent prime-target trials, our prime-target pairs that were separated by intervening trials were not significant. These findings suggest follow-up studies to clarify the effects of structural priming in a long term setting. / A Thesis submitted to the Department of Psychology in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester 2018. / November 8, 2018. / language production, psycholinguistics, structural priming / Includes bibliographical references. / Michael P. Kaschak, Professor Directing Thesis; Walter R. Boot, Committee Member; Andrea Meltzer, Committee Member.
219

Examining Sex Differences and the Effects of Videogame Experience on Development of Manual Control Skill in a Novel Action Videogame

Unknown Date (has links)
Many classical studies examining sex differences in visuospatial abilities have shown a male advantage in measures of skills like mental rotation and spatial navigation. However, a number of investigations of strategy selection differences between men and women have begun to question the notion that individual differences in general skills may be the primary explanation for the observed sex differences in performance. Another line of individual-differences-focused research has examined the effects of videogame experience on development of visuospatial skills, and several studies have found that individuals with an extensive history of action videogame play demonstrate superior performance on tasks demanding dynamic spatial cognition. Some researchers have proposed the likely explanatory mechanism for this phenomenon is that action videogame play encourages growth of generalizable enhancements to attentional control or cognitive flexibility. Extending from these findings, the effects of sex differences and videogame experience have recently come together in a series of studies positing that action videogame training can reduce observed sex differences in visuospatial skills. One of the major limitations of the existing videogame training literature is that very little behavioral data is typically collected during the training tasks, so it is unclear what patterns of behavior these participants are executing while performing the tasks. Thus, many of the conclusions regarding the role of individual differences in explaining participant performance are made without considering how participant strategy selection may also be contributing to performance. Additionally, individuals with extensive action videogame experience may become highly familiarized with a particular control interface, which could vary considerably from game to game, and the design of the control interface may have a nontrivial influence on learning a novel visuospatially-demanding task. The present study examined sex differences, the effect of prior action videogame experience, and the influence of varying control interfaces on participants' development of control performance across ten games of a novel action videogame, Space Fortress. Latent curve analyses revealed significant sex differences in control skill performance, indicating non-gamer men displayed better performance overall than non-gamer women. A significant gaming experience by interface interaction indicated that men with extensive action videogame experience outperformed men with very little gaming experience, but this performance advantage was limited to playing with the keyboard interface. Investigation of player behavior revealed that a participants' ship control behaviors were associated with observed sex and gaming experience differences. Additionally, it was found that playing the game with a keyboard-and-mouse interface was generally associated with better performance than playing with a joystick-and-mouse interface. Finally, analysis of variance testing was performed to compare levels of understanding of the game's control mechanics across sex and gaming experience categories, revealing that men and gamers displayed greater knowledge of Space Fortress ship control procedures than women and non-gamers, respectively. Results are discussed in the context of existing sex differences and videogame training literature. The present investigation extends previous research by presenting evidence that strategy selection differences may play a crucial role in explaining the origins of sex differences and calls into question current models of complex skill learning that argue extensive action videogame experience may be associated with enhanced cognitive processes. / A Thesis submitted to the department of Psychology in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester 2018. / August 22, 2018. / Includes bibliographical references. / K. Anders Ericsson, Professor Directing Thesis; Walter R. Boot, University Representative; Colleen M. Ganley, Committee Member.
220

Investigating the Effects of Multiple Advanced Driver Assistance Systems on Older Drivers' Simulated Driving Performance and System Acceptance

Unknown Date (has links)
The number of crash-related fatalities in the United States climbed to over 35 thousand from 2014 to 2015, representing a 7.2% increase, and ending a 50-year trend of decline in this rate (NHTSA, 2016). The ability to drive safely represents an important activity of daily life that is closely tied to maintaining independence in old age (Persson, 1993), and with more older drivers logging more vehicle miles travelled than in previous cohorts, supporting safe driving in this age group is paramount. Advanced driver assistance systems (ADAS) are rapidly being introduced into new vehicles with each successive model year, and their incorporation into the driving task stands to bring many safety and convenience benefits to drivers of all ages. Despite the hope that the addition of more ADAS into the driving task leads to an additive safety benefit, previous research conducted in samples comprised largely of younger to middle-aged adult suggests otherwise. Also, safety benefits may not be realized if these vehicle technologies are not adopted, or if the incorporation of multiple systems leads to reductions in driving performance due to mode confusion, overreliance, or increased distraction. This dissertation provided a sample of older drivers (N = 101) experience with either a longitudinal warning system (Forward Collision Warning; FCW), a lateral warning system (Lane Departure Warning; LDW), or both systems over the course of a simulated drive to gauge effects on driving performance, as well as attitudes toward the system. Headway distance was not found to differ across groups, but drivers that received lateral warnings were found to show less deviation from lane center than drivers who did not receive lateral warnings. Attitudes toward these systems were found to be mostly positive prior to the simulated drive, and experience with the assigned system did not significantly alter these perceptions post-drive. / A Dissertation submitted to the Department of Psychology in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2017. / December 13, 2017. / Aging, Forward Collision Warning, Human Factors, Lane Departure Warning, Transportation / Includes bibliographical references. / Neil Charness, Professor Directing Dissertation; Mark Horner, University Representative; Walter Boot, Committee Member; K. Anders Ericsson, Committee Member; James McNulty, Committee Member.

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