Matching Items (11)
Description
Although it has recently been demonstrated that source monitoring (SM) processes may mediate the relationship between working memory (WM) and false memories, little research has investigated whether the quality of monitoring processes can account for this reduction. In the current study, participants performed multiple false memory, WM, and SM tasks. Consistent with previous research, SM abilities mediated the relationship between WM and false memories (regardless of whether or not participants were warned of the illusions at encoding). High SM individuals were better able to recall contextual information from study to correctly reject lures, whereas low SM individuals were more likely to rely on the quality of retrieved details to reject lures. These results suggest that individuals low and high in SM abilities rely on qualitatively different monitoring processes to reduce errors, and that individual differences in diagnostic monitoring strategies may account for previous relationships found between WM and false memories.
ContributorsCoulson, Allison Rose (Author) / Brewer, Gene (Thesis director) / Ellis, Derek (Committee member) / Department of Psychology (Contributor) / School of Public Affairs (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Problem solving is a crucial skill needed to accomplish everyday tasks and overcome potential obstacles. One way to measure individual differences in problem solving ability is through performance differences on multiply-constrained problem solving tasks. Multiple cognitive processes are involved in multiply-constrained problem solving. An individual uses prospective metacognitive monitoring judgments to gauge future allocation of resources before engaging in the necessary semantic search. Problem solvers also vary in their semantic search strategies, and use either an active analytical strategy or a passive insight strategy to arrive at asolution. Prospective metacognitive monitoring judgments and solution strategies are two aspects of the problem solving process that occur at specific points in the process while motivation influences problem solving throughout the process. The goal of this study is to examine prospective metacognitive judgments, problem solving accuracy, solution strategy, and motivation in multiply-constrained problem solving. Motivation was manipulated using a performance based monetary incentive. Participants self reported prospective Feeling-of-Knowing judgments after brief exposure to the problem, and solution strategy ratings after each problem. No significant differences were found to support the effect of motivation on problem solving accuracy, prospective metacognitive judgments, relative accuracy, or solution strategies. Significant differences were found between groups when comparing the number of problems skipped, indicating that participants were sensitive to the incentive structure. The findings suggest that motivation may not be an overarching mediator in multiply-constrained problem solving or problem solving may require a specific type of incentive structure to increase accuracy. However, little is known in the research literature about the type of incentive structure needed to consistently increase individual motivation.
ContributorsCohen, Aaron Sayre (Author) / Brewer, Gene (Thesis director) / Ellis, Derek (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Research has demonstrated observers have a generic bias for top saliency in object identification, such that random shapes appear more similar to ones that share the same tops versus same bottoms (Chambers et al., 1999). These findings are consistent with the idea that in nature, the tops of most important objects and living things tend to be the most informative locations with respect to intentionality and functionality, leading observers to favor attending to top. Yet, such a bias also may imply a generic downward vantage bias, suggesting that unlike natural objects, the more informative aspects of scenes tend to lie below their horizon midpoints. In two experiments, saliency bias was investigated for objects and scenes with both information-balanced and naturalistic stimuli. Experiment 1 replicates and extends the study of the top-saliency effect for information-balanced objects. Here 91 participants made 80 similarity judgments between an information-balanced object and two comparison objects that contain either the same top or the same bottom. Participants also made 80 similarity judgments of information-balanced scenes in which the coordinates of the vertices of the random shapes were replaced with little objects to create a scene. Experiment 2 extends Chambers et al. (1999) by examining top-saliency bias in naturalistic object perception when 91 participants made similarity judgments between a photographed test object and two comparison objects which contain either the same top or the same bottom. Experiment 2 also tests the idea of a downward vantage bias by predicting that naturalistic scenes will be judged more similar when the portions that lie below the horizon are identical versus when the portions above are the same. Results of the two experiments confirm that observers tend to assume a downward vantage when viewing pictures of objects and objects within scenes, which supports that saliency varies as a function of the informative aspect of the visually attended component.
ContributorsLangley, Matthew (Author) / Mcbeath, Michael K (Thesis advisor) / Brewer, Gene A (Committee member) / Lucca, Kelsey (Committee member) / Arizona State University (Publisher)
Created2021
Description
Sustained attention, the ability to concentrate on a stimulus or task over a prolonged period, is essential for goal pursuit and fulfillment. Sustained attention failures can have catastrophic consequences, underscoring the importance of understanding the mechanisms that underlie variability in sustained attention, and developing interventions targeting these mechanisms to reduce such failures. A growing body of research implicates the brainstem locus coeruleus (LC) as a core modulator of attention and arousal. Activation of LC afferents, such as the trigeminal nerve, may indirectly modulate the LC. The altered LC activity could theoretically be tracked via well-established psychological and physiological indicators of attention and arousal, such as performance, self-reports of attention state, and pupillary activity during attention tasks. The present study tests the hypothesis that continuous transcranial direct current stimulation (tDCS) over the trigeminal nerve of the face improves attentional state, attentional performance, and pupillary reactivity via indirect modulation of the LC. Participants received 2 mA of anodal or cathodal stimulation or sham stimulation over the dorsolateral prefrontal cortex while completing the Psychomotor Vigilance Task. Participants occasionally reported on their attentional state. Pupillary activity was recorded continuously throughout the task. To compare patterns of attention task performance, frequency of task-unrelated thoughts, and pupillary activity across time by stimulation condition, linear mixed-effects models were implemented.
The results replicate the complex interplay between attentional state, attentional performance, and pupillary activity reported in the literature. Specifically, a ubiquitous pattern of performance deterioration was observed, which coincided with an increase in task-unrelated thoughts and reduced pretrial and task-evoked pupil responses. However, tDCS over the face did not produce significant effects compared to the sham condition in attention task performance, proportion of task-unrelated thoughts, and pupillary activity that would indicate LC modulation. This study addresses the causal relations between LC activity, attentional state, attentional performance, and pupillary reactivity that are still poorly understood in human subjects. The findings reported here support the dominant theory of the role of the LC in attentional processes but fail to support hypotheses suggesting that tDCS of the trigeminal nerve influences activity of the LC and indicators of LC activity.
ContributorsTorres, Alexis Stephanie (Author) / Brewer, Gene A (Thesis advisor) / Robison, Matthew K (Committee member) / McClure, Samuel M (Committee member) / Helms Tillery, Stephen (Committee member) / Arizona State University (Publisher)
Created2022
Description
An important facet of daily memory function is prospective memory, which is one’s ability to complete established intentions in the appropriate temporal and spatial context. Many factors contribute to impairments in prospective memory, such as limited cognitive resources or aging. A factor that has been subject to recent investigation is how cannabis use may have an impact on the mechanisms that contribute to prospective memory. Cannabis use has been on the rise across the world, and in the United States more states are pushing to legalize its recreational use, if they haven’t already. As this substance becomes more easily accessible, akin to alcohol use, the necessity to investigate its potential consequences on cognition is needed now more than ever. Prospective memory is an appropriate measure of cannabis-induced deficits due to the wide literature looking at neural correlates of the component mechanisms that contribute to successful prospective memory, attentional and memory processes. The current study employed two experiments to measure this argued claim. Experiment 1 replicated well-defined effects from the prospective memory literature by measuring task accuracy (memory), response times (attention), and pupillary dynamics (attention). Informed by the research looking at the brain regions suspected of experiencing the most functional impairment, Experiment 2 aimed to extend these findings with a sample of participants following acute cannabis administration, however, results indicated cannabis group performance was similar in accuracy and showed faster mean latencies to that of the control group.
ContributorsCelaya, Xavier Lorenzo (Author) / Brewer, Gene A (Thesis advisor) / Meier, Madeline H (Committee member) / Lewis, Candace R (Committee member) / Arizona State University (Publisher)
Created2023
Description
The emotional enhancement of memory (EEM) has consistently suggested that memory performance is enhanced for positively and negatively valenced stimuli. Heightened arousal and activation of the noradrenergic system facilitates encoding and the formation of memory traces. However, this EEM can become maladaptive when coupled with the heightened noradrenergic activity associated with posttraumatic stress disorder (PTSD). This heightened noradrenergic response can result in chronic intrusive memories of past traumatic events. This study aims to explore overall recall, retrieval dynamics, output editing, and intrusions as a function of emotional content and prior history with traumatic experiences. Undergraduate students (N=249) from Arizona State University completed a battery surveys measuring PTSD symptomatology and other related constructs including anxiety, depression, and trauma. Participants then completed a memory task, an externalized free recall task for multiple study-blocks utilizing word list stimuli. During recall, participants were instructed to report every word that came to mind regardless of whether it was present or not in the most recent study-block, then make a judgment about recent-list membership. Main effects of valence were found for recall accuracy, intrusion generation, and successful editing. This suggests that the emotional enhancement of memory does in fact play a role in intrusion generation and the ability to edit out false recollections. Only depression levels resulted in a significant interaction effect with valence, specifically when measuring intrusion generation. This suggests that trauma level does not play a significant role in emotional intrusion memory.
ContributorsDziendziel, Hailey K (Author) / Brewer, Gene A (Thesis advisor) / Azuma, Tamiko (Committee member) / Lewis, Candace (Committee member) / Arizona State University (Publisher)
Created2023
Description
Humans are biased toward teleological explanations of natural phenomena. The promiscuous teleology account posits that this proclivity is rooted in the detection of supernatural agency behind the design of the natural world. This idea is supported by numerous positive correlations of religious belief and agreement with teleological explanations of natural phenomena, but it is challenged by findings that non-believers often agree with them as well, suggesting the need for an adjudicating experiment. The current experiment tested whether considering similar teleological explanations of nature causes explicitly theistic and atheistic people to think about God, which would suggest that the teleological bias has roots in agency detection. Participants (N = 608) were randomly assigned to consider teleological explanations of either human-caused phenomena or natural phenomena, with the main prediction that considering the natural item set would make theists relatively faster to categorize God as real but make atheists relatively slower to categorize God as imaginary. The data did support this hypothesis, suggesting that people across the theistic belief spectrum automatically think of God when thinking about nature’s purpose, and thus the teleological bias might be rooted in the detection of supernatural agency. Implications for theories of teleology, study limitations, and potential future directions are discussed.
ContributorsScott, Matthew (Author) / Cohen, Adam B (Thesis advisor) / Kenrick, Douglas T (Committee member) / Brewer, Gene A (Committee member) / Becker, David Vaughn (Committee member) / Arizona State University (Publisher)
Created2021
Description
Capacity limits of the human nervous system require important or rewarding information to be prioritized and encoded over less important or rewarding information. The present dissertation aims to identify structural and functional neural correlates of reward-motivated memory encoding. Chapter 1 reviews studies of reward-motivated memory encoding and their neural correlates, as well as the structure and function of dopaminergic midbrain circuits. Chapter 2 presents a study that utilizes electroencephalography (EEG) to determine which of two hypothesized processes underly the influence of reward value on episodic memory. One hypothesis is that value engages prefrontal executive control processes, so that valuable stimuli engage an elaborative rehearsal strategy that benefits memory. A second hypothesis is that value acts through the reward-related midbrain dopamine system to modulate synaptic plasticity in hippocampal and cortical efferents, thereby benefiting memory encoding. The results revealed that EEG signals thought to index dopamine-driven attention allocation were modulated by reward value and were positively correlated with individual differences in behavioral measures of memory prioritization. Chapter 3 employs diffusion-weighted magnetic resonance imaging (MRI) to dissociate heterogenous functional circuits of the midbrain reward system. The results comport with primate histology and show that midbrain circuits are differentially predictive of impulsivity and of attention-deficit hyperactivity disorder (ADHD). Chapter 4 presents a study that also employs diffusion-weighted MRI. The findings replicate Chapter 3 in dissociating heterogenous functional circuits of the midbrain reward system. Additionally, the structural integrity of midbrain-hippocampus circuits was quantified. Structural integrity of these circuits was positively correlated to behavioral measures of memory prioritization. These findings suggest that structural and functional measures of the dopaminergic reward system may underlie reward-motivated memory encoding in humans.
ContributorsElliott, Blake Louis (Author) / Brewer, Gene A (Thesis advisor) / McClure, Samuel M (Committee member) / Sanabria, Federico (Committee member) / Bae, Gi-Yeul (Committee member) / Arizona State University (Publisher)
Created2021
Description
Source monitoring refers to the ability to discriminate the origins of memories. The source monitoring framework is a theoretical model that describes the various characteristics of memories and judgement processes necessary for this discrimination process. Little research has analyzed the extent to which predictable encoding contexts influence source monitoring processes. In this study, we found that predictability at encoding aids later source recognition, but only when the test-relevant source dimension was predictable at encoding. The encoding format was either predictable (sequential spatial location) or non-predictable (random spatial location) and the test format was either color or location. In Experiment 1, the encoding format was either predictable or non-predictable spatial locations and participants were tested on the location. In this experiment, predictability did aid when the encoding format matched the test format. The average conditionalized source identification measure was statistically higher for those who saw images appear in a predictable pattern at encoding. In Experiment 2, when participants were tested on an orthogonal source dimension, the average conditionalized source identification measure was not statistically significant for those who saw the images appear in either encoding format. In this experiment, the predictability did not have an effect when the encoding format did not match the test format. In Experiment 3, there was a significant interaction of predictability by source dimension showing an improvement to memory for the predictable source condition and a decrement to memory for the unpredictable source dimension. In this experiment, predictability aided when encoding format matched the test format, but not when the encoding and test format did not match.
ContributorsDickson, Katrina Rebecca (Author) / Brewer, Gene (Thesis director) / Benitez, Viridiana (Committee member) / Ellis, Derek (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / College of Health Solutions (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Human potential is characterized by our ability to think flexibly and develop novel solutions to problems. In cognitive neuroscience, problem solving is studied using various tasks. For example, IQ can be tested using the RAVEN, which measures abstract reasoning. Analytical problem solving can be tested using algebra, and insight can be tested using a nine-dot test. Our class of problem-solving tasks blends analytical and insight processes. This can be done by measuring multiply-constrained problem solving (MCPS). MCPS occurs when an individual problem has several solutions, but when grouped with simultaneous problems only one correct solution presents itself. The most common test for MCPS is known at the CRAT, or compound remote associate task. For example, when given the three target words “water, skate, and cream” there are many compound associates that can be assigned each of the target words individually (i.e. salt-water, roller-skate, whipped-cream), but only one that works with all three (ice-water, ice-skate, ice-cream).
This thesis is a tutorial for a MATLAB user-interface, known as EEGLAB. Cognitive and neural correlates of analytical and insight processes were evaluated and analyzed in the CRAT using EEG. It was hypothesized that different EEG signals will be measured for analytical versus insight problem solving, primarily observed in the gamma wave production. The data was interpreted using EEGLAB, which allows psychological processes to be quantified based on physiological response. I have written a tutorial showing how to process the EEG signal through filtering, extracting epochs, artifact detection, independent component analysis, and the production of a time – frequency plot. This project has combined my interest in psychology with my knowledge of engineering and expand my knowledge of bioinstrumentation.
This thesis is a tutorial for a MATLAB user-interface, known as EEGLAB. Cognitive and neural correlates of analytical and insight processes were evaluated and analyzed in the CRAT using EEG. It was hypothesized that different EEG signals will be measured for analytical versus insight problem solving, primarily observed in the gamma wave production. The data was interpreted using EEGLAB, which allows psychological processes to be quantified based on physiological response. I have written a tutorial showing how to process the EEG signal through filtering, extracting epochs, artifact detection, independent component analysis, and the production of a time – frequency plot. This project has combined my interest in psychology with my knowledge of engineering and expand my knowledge of bioinstrumentation.
ContributorsCobban, Morgan Elizabeth (Author) / Brewer, Gene (Thesis director) / Ellis, Derek (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05