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- Member of: Theses and Dissertations
Description
In most of the work using event-related potentials (ERPs), researchers presume the function of specific components based on the careful manipulation of experimental factors, but rarely report direct evidence supporting a relationship between the neural signal and other outcomes. Perhaps most troubling is the lack of evidence that ERPs correlate with related behavioral outcomes which should result, at least in part, from the neural processes that ERPs capture. One such example is the NoGo-N2 component, an ERP component elicited in Go/NoGo paradigms. There are two primary theories regarding the functional significance of this component in this context: that the signal represents response inhibition and that the component reflects conflict. In this paper, a trial-level method of analysis for the relationship between ERP component potentials and downstream behavioral outcomes (in this case, response accuracy) using a multi-level modeling framework is proposed to provide discriminatory evidence for one of these theories. Following a description of the research on the NoGo-N2, preliminary data supporting the conflict monitoring theory are presented, noting important limitations. Next, an EEG simulation study is presented in which NoGo-N2 data are generated with a known relationship to fabricated reaction time data, showing that, with added levels of complexity and noise within the data, the MLM approach is consistently successful at extracting the known relationships that occur in real NoGo-N2 data. Next, using independent components analysis (ICA) to extract spatiotemporal components that best represent the signal of interest, a well-powered analysis of the relationship between the NoGo-N2 and response accuracy is used to provide strong discriminatory evidence for the conflict monitoring theory of the NoGo-N2. Finally, implications for the NoGo-N2, as well as all ERP components, are discussed with a focus on how this approach can and should be used. the paper concludes with potential expansions of this approach to areas beyond identifying the function of ERP components.
ContributorsHampton, Ryan Scott (Author) / Varnum, Michael E.W. (Thesis advisor) / Shiota, Michelle N. (Committee member) / Brewer, Gene A. (Committee member) / Blais, Chris (Committee member) / Arizona State University (Publisher)
Created2019
Description
In everyday life, mental fatigue can be detrimental across many domains including driving, learning, and working. Given the importance of understanding and accounting for the deleterious effects of mental fatigue on behavior, a growing body of literature has studied the role of executive control processes in mental fatigue. In a laboratory setup, participants complete a task that places demands on executive control processes and are later given a transfer task. Generally speaking, decrements to subsequent task performance are taken as evidence that the initial executive control task created mental fatigue through the continued engagement of executive control. Several hypotheses have been developed to account for negative transfer resulting from executive control depletion including cognitive resource depletion and task-switching. In the current study, we provide a brief literature review, specify current theoretical approaches to depletion, and provide a strong empirical test of theories for negative transfer from executive control depletion (i.e., does continued performance of an executive control task negatively transfer to that exact same task).
ContributorsLau, Kin Hang (Author) / Brewer, Gene (Thesis director) / Knight, George (Committee member) / Blais, Chris (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Psychology (Contributor)
Created2014-12
Effects of Assisted Cycle Therapy on Short Term and Working Memory in Adolescents with Down Syndrome
Description
To examine the effect of an 8-week cycling intervention on short term and working memory in adolescents with Down syndrome (DS), participants were divided into Assisted Cycling Therapy (ACT), Voluntary Cycling (VC), or No Cycling (NC) groups. Forward and backward digit span assessments were administered prior to and after the intervention to evaluate short term and working memory respectively. 8 weeks of exercise via ACT showed a trend toward conventional levels of significance in the number of levels completed in the backward direction.
ContributorsSandoval-Menendez, Amber Melanie (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Blais, Chris (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
Recognition memory is examined by exposing a person to a stimulus and later prompting them with the same stimulus to examine their ability to accurately acknowledge that the stimulus was previously encountered (Kahana, 2012). In recognition memory, confidence ratings are taken during the testing phase to assess how confident the participant is that the old-new judgment that they just made is accurate (Busey et al., 2000). Confidence is a metacognitive assessment about the accuracy of perception of decision making based on the amount, speed, and clarity of thoughts that come to mind (Dunlosky and Metcalfe, 2008). The goal of the current study is to better understand how assessing recognition memory using a variety of test procedures influences memory accuracy using the signal detection theory and adding multiple confidence scales that vary in granularity. Based on the previous literature, it is hypothesized that; 1) tasks ordered sequentially will produce greater recognition accuracy (d') than the simultaneous (dual task) condition; 2) confidence scale of 3 points will produce a larger d' than the 7 point scale, and the 7 point scale will produce a larger d' than the 100 point scale; and 3) task mode (ordered vs. sequenced) will interact with confidence scale granularity to predict memory accuracy, such that sequential judgments lessen demands on working memory that come from maintaining an increasing number of decision criteria in comparison to the dual task. Results indicated all hypotheses were not upheld. The findings suggest that taxing working memory may not affect decisional accuracy on a recognition task incorporating confidence judgments.
ContributorsSullivan, Krysten Jennifer (Author) / Brewer, Gene (Thesis director) / Blais, Chris (Committee member) / Davis, Mary (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Language comprehension is an essential skill in many aspects of life, yet some children still struggle with oral comprehension. This study examined the effectiveness of an intervention to improve the listening skills and comprehension of 4 and 5-year olds. This intervention is based on principles of embodied cognition, namely that language comprehension requires a simulation (or imagination) of what the language is about. Thus, children in the intervention condition moved pictures on an iPad to simulate the stories they were hearing. Children in the control condition saw the pictures, but did not move them. To identify the effectiveness of this simulation training, we analyzed scores on a comprehension test, and changes in motor cortex activity while listening. If the intervention increases simulation, then compared to the control, a) children given the intervention should perform better on the comprehension test, and b) those children should show greater activity in their motor cortices while listening. Furthermore, the change in motor cortex activity should statistically mediate the change in comprehension. Our results showed a significant positive correlation (.79) in the EMBRACE group (but not in the control) between the change in mu suppression before and after the intervention and the change in comprehension questions before and after the intervention. This correlation suggests that children can be taught to use their motor cortices while listening, and supports our hypothesis that embodied language theories, such as simulation are useful for enhancing comprehension.
ContributorsMarji, Michelle Lee (Author) / Glenberg, Arthur (Thesis director) / Blais, Chris (Committee member) / Restrepo, Laida (Committee member) / School of Film, Dance and Theatre (Contributor) / Department of Psychology (Contributor) / Herberger Institute for Design and the Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Working memory is the cognitive system responsible for storing and maintaining information in short-term memory and retrieving cues from long-term memory. Working memory capacity (WMC) is needed for goal maintenance and to ignore task-irrelevant stimuli (Engle & Kane, 2003). Emotions are one type of task-irrelevant stimuli that could distract an individual from a task (Smallwood, Fitzgerald, Miles, & Phillips, 2009). There are studies that show there is a relation between emotions and working memory capacity. The direction of this relationship, though, is unclear (Kensinger, 2009). In this study, emotions served as a distractor and task performance was examined for differences in the effect of emotion depending on participants' working memory capacity. The participants watched a mood induction video, then were told to complete a complex-span working memory task. The mood induction was successful- participants watching the negative emotional video were in a less positive mood after watching the video than the participants that watched a neutral video. However, the results of the complex-span working memory task showed no significant difference in the results between participants in the negative versus neutral mood. These results may provide support to an alternative hypothesis: cognitive tasks can diminish the effects of emotions (Dillen, Heslenfeld, & Koole, 2009).
ContributorsAhmed, Sania (Author) / Brewer, Gene (Thesis director) / Wingert, Kimberly (Committee member) / Blais, Chris (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Working memory is the cognitive system responsible for storing and maintaining information in short-term memory and retrieving cues from long-term memory. Working memory capacity (WMC) is needed for goal maintenance and to ignore task-irrelevant stimuli (Engle & Kane, 2003). Emotions are one type of task-irrelevant stimuli that could distract an individual from a task (Smallwood, Fitzgerald, Miles, & Phillips, 2009). There are studies that show there is a relation between emotions and working memory capacity. The direction of this relationship, though, is unclear (Kensinger, 2009). In this study, emotions served as a distractor and task performance was examined for differences in the effect of emotion depending on participants' working memory capacity. The participants watched a mood induction video, then were told to complete a complex-span working memory task. The mood induction was successful- participants watching the negative emotional video were in a less positive mood after watching the video than the participants that watched a neutral video. However, the results of the complex-span working memory task showed no significant difference in the results between participants in the negative versus neutral mood. These results may provide support to an alternative hypothesis: cognitive tasks can diminish the effects of emotions (Dillen, Heslenfeld, & Koole, 2009).
ContributorsAhmed, Sania (Author) / Brewer, Gene (Thesis director) / Wingert, Kimberly (Committee member) / Blais, Chris (Committee member) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The premise of the embodied cognition hypothesis is that cognitive processes require emotion, sensory, and motor systems in the brain, rather than using arbitrary symbols divorced from sensorimotor systems. The hypothesis explains many of the mechanisms of mental simulation or imagination and how they facilitate comprehension of concepts. Some forms of embodied processing can be measured using electroencephalography (EEG), in a particular waveform known as the mu rhythm (8-13 Hz) in the sensorimotor cortex of the brain. Power in the mu band is suppressed (or de-synchronized) when an individual performs an action, as well as when the individual imagines performing the action, thus mu suppression measures embodied imagination. An important question however is whether the sensorimotor cortex involvement while reading, as measured by mu suppression, is part of the comprehension of what is read or if it is arises after comprehension has taken place. To answer this question, participants first took the Gates-MacGinitie reading comprehension test. Then, mu-suppression was measured while participants read experimental materials. The degree of mu-suppression while reading verbs correlated .45 with their score on the Gates-MacGinitie test. This correlation strongly suggests that the sensorimotor system involvement while reading action sentences is part of the comprehension process rather than being an aftereffect.
ContributorsMarino, Annette Webb (Author) / Glenberg, Arthur (Thesis director) / Presson, Clark (Committee member) / Blais, Chris (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Most theories of cognitive control assume goal-directed behavior takes the form of performance monitor-executive function-action loop. Recent theories focus on how a single performance monitoring mechanism recruits executive function - dubbed single-process accounts. Namely, the conflict-monitoring hypothesis proposes that a single performance monitoring mechanism, housed in the anterior cingulate cortex, recruits executive functions for top-down control. This top-down control manifests as trial-to-trial micro adjustments to the speed and accuracy of responses. If these effects are produced by a single performance monitoring mechanism, then the size of these sequential trial-to-trial effects should be correlated across tasks. To this end, we conducted a large-scale (N=125) individual differences experiment to examine whether two sequential effects - the Gratton effect and error-related slowing effect - are correlated across a Simon, Flanker, and Stroop task. We find weak correlations for these effects across tasks which is inconsistent with single-process accounts.
ContributorsWhitehead, Peter Stefan Sekerere (Author) / Brewer, Gene (Thesis director) / Blais, Chris (Committee member) / Rogalsky, Corianne (Committee member) / Department of Psychology (Contributor) / School of Music (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
Abstract: Behavioral evidence suggests that joint coordinated movement attunes one's own motor system to the actions of another. This attunement is called a joint body schema (JBS). According to the JBS hypothesis, the attunement arises from heightened mirror neuron sensitivity to the actions of the other person. This study uses EEG mu suppression, an index of mirror neuron system activity, to provide neurophysiological evidence for the JBS hypothesis. After a joint action task in which the experimenter used her left hand, the participant's EEG revealed greater mu suppression (compared to before the task) in her right cerebral hemisphere when watching a left hand movement. This enhanced mu suppression was found regardless of whether the participant was moving or watching the experimenter move. These results are suggestive of super mirror neurons, that is, mirror neurons which are strengthened in sensitivity to another after a joint action task and do not distinguish between whether the individual or the individual's partner is moving.
ContributorsGoodwin, Brenna Renee (Author) / Glenberg, Art (Thesis director) / Presson, Clark (Committee member) / Blais, Chris (Committee member) / School of Historical, Philosophical and Religious Studies (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12