Matching Items (3)
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- All Subjects: compound remote associate
- All Subjects: Free Recall
- Creators: Brewer, Gene A
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
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
Individuals encounter problems daily wherein varying numbers of constraints require delimitation of memory to target goal-satisfying information. Multiply-constrained problems, such as compound remote associates, are commonly used to study this type of problem solving. Since their development, multiply-constrained problems have been theoretically and empirically related to creative thinking, analytical problem solving, insight problem solving, intelligence, and a multitude of other cognitive abilities. Critically, in order to correctly solve a multiply-constrained problem the solver must have the solution available in memory and be able to target and access to that information. Experiment 1 determined that the cue – target relationship affects the likelihood that a problem is solved. Moreover, Experiment 2 identified that the association between cues and targets predicted inter- & intra-individual differences in multiply-constrained problem solving. Lastly, Experiment 3 found monetary incentives failed to improve problem solving performance likely due to knowledge serving as a limiting factor on performance. Additionally, problem solvers were shown to be able to reliably assess the likelihood they would solve a problem. Taken together all three studies demonstrated the importance of knowledge & knowledge structures on problem solving performance.
ContributorsEllis, Derek (Author) / Brewer, Gene A (Thesis advisor) / Homa, Donald (Committee member) / Blais, Chris (Committee member) / Goldinger, Stephen (Committee member) / Arizona State University (Publisher)
Created2021