Matching Items (8)
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- All Subjects: Memory
- All Subjects: decision-making
- Creators: Azuma, Tamiko
Description
It is commonly known that the left hemisphere of the brain is more efficient in the processing of verbal information, compared to the right hemisphere. One proposal suggests that hemispheric asymmetries in verbal processing are due in part to the efficient use of top-down mechanisms by the left hemisphere. Most evidence for this comes from hemispheric semantic priming, though fewer studies have investigated verbal memory in the cerebral hemispheres. The goal of the current investigations is to examine how top-down mechanisms influence hemispheric asymmetries in verbal memory, and determine the specific nature of hypothesized top-down mechanisms. Five experiments were conducted to explore the influence of top-down mechanisms on hemispheric asymmetries in verbal memory. Experiments 1 and 2 used item-method directed forgetting to examine maintenance and inhibition mechanisms. In Experiment 1, participants were cued to remember or forget certain words, and cues were presented simultaneously or after the presentation of target words. In Experiment 2, participants were cued again to remember or forget words, but each word was repeated once or four times. Experiments 3 and 4 examined the influence of cognitive load on hemispheric asymmetries in true and false memory. In Experiment 3, cognitive load was imposed during memory encoding, while in Experiment 4, cognitive load was imposed during memory retrieval. Finally, Experiment 5 investigated the association between controlled processing in hemispheric semantic priming, and top-down mechanisms used for hemispheric verbal memory. Across all experiments, divided visual field presentation was used to probe verbal memory in the cerebral hemispheres. Results from all experiments revealed several important findings. First, top-down mechanisms used by the LH primarily used to facilitate verbal processing, but also operate in a domain general manner in the face of increasing processing demands. Second, evidence indicates that the RH uses top-down mechanisms minimally, and processes verbal information in a more bottom-up manner. These data help clarify the nature of top-down mechanisms used in hemispheric memory and language processing, and build upon current theories that attempt to explain hemispheric asymmetries in language processing.
ContributorsTat, Michael J (Author) / Azuma, Tamiko (Thesis advisor) / Goldinger, Stephen D (Committee member) / Liss, Julie M (Committee member) / Arizona State University (Publisher)
Created2013
Description
Previous research from Rajsic et al. (2015, 2017) suggests that a visual form of confirmation bias arises during visual search for simple stimuli, under certain conditions, wherein people are biased to seek stimuli matching an initial cue color even when this strategy is not optimal. Furthermore, recent research from our lab suggests that varying the prevalence of cue-colored targets does not attenuate the visual confirmation bias, although people still fail to detect rare targets regardless of whether they match the initial cue (Walenchok et al. under review). The present investigation examines the boundary conditions of the visual confirmation bias under conditions of equal, low, and high cued-target frequency. Across experiments, I found that: (1) People are strongly susceptible to the low-prevalence effect, often failing to detect rare targets regardless of whether they match the cue (Wolfe et al., 2005). (2) However, they are still biased to seek cue-colored stimuli, even when such targets are rare. (3) Regardless of target prevalence, people employ strategies when search is made sufficiently burdensome with distributed items and large search sets. These results further support previous findings that the low-prevalence effect arises from a failure to perceive rare items (Hout et al., 2015), while visual confirmation bias is a bias of attentional guidance (Rajsic et al., 2015, 2017).
ContributorsWalenchok, Stephen Charles (Author) / Goldinger, Stephen D (Thesis advisor) / Azuma, Tamiko (Committee member) / Homa, Donald (Committee member) / Hout, Michael C (Committee member) / McClure, Samuel M. (Committee member) / Arizona State University (Publisher)
Created2018
Description
Cognitive deficits often accompany language impairments post-stroke. Past research has focused on working memory in aphasia, but attention is largely underexplored. Therefore, this dissertation will first quantify attention deficits post-stroke before investigating whether preserved cognitive abilities, including attention, can improve auditory sentence comprehension post-stroke. In Experiment 1a, three components of attention (alerting, orienting, executive control) were measured in persons with aphasia and matched-controls using visual and auditory versions of the well-studied Attention Network Test. Experiment 1b then explored the neural resources supporting each component of attention in the visual and auditory modalities in chronic stroke participants. The results from Experiment 1a indicate that alerting, orienting, and executive control are uniquely affected by presentation modality. The lesion-symptom mapping results from Experiment 1b associated the left angular gyrus with visual executive control, the left supramarginal gyrus with auditory alerting, and Broca’s area (pars opercularis) with auditory orienting attention post-stroke. Overall, these findings indicate that perceptual modality may impact the lateralization of some aspects of attention, thus auditory attention may be more susceptible to impairment after a left hemisphere stroke.
Prosody, rhythm and pitch changes associated with spoken language may improve spoken language comprehension in persons with aphasia by recruiting intact cognitive abilities (e.g., attention and working memory) and their associated non-lesioned brain regions post-stroke. Therefore, Experiment 2 explored the relationship between cognition, two unique prosody manipulations, lesion location, and auditory sentence comprehension in persons with chronic stroke and matched-controls. The combined results from Experiment 2a and 2b indicate that stroke participants with better auditory orienting attention and a specific left fronto-parietal network intact had greater comprehension of sentences spoken with sentence prosody. For list prosody, participants with deficits in auditory executive control and/or short-term memory and the left angular gyrus and globus pallidus relatively intact, demonstrated better comprehension of sentences spoken with list prosody. Overall, the results from Experiment 2 indicate that following a left hemisphere stroke, individuals need good auditory attention and an intact left fronto-parietal network to benefit from typical sentence prosody, yet when cognitive deficits are present and this fronto-parietal network is damaged, list prosody may be more beneficial.
Prosody, rhythm and pitch changes associated with spoken language may improve spoken language comprehension in persons with aphasia by recruiting intact cognitive abilities (e.g., attention and working memory) and their associated non-lesioned brain regions post-stroke. Therefore, Experiment 2 explored the relationship between cognition, two unique prosody manipulations, lesion location, and auditory sentence comprehension in persons with chronic stroke and matched-controls. The combined results from Experiment 2a and 2b indicate that stroke participants with better auditory orienting attention and a specific left fronto-parietal network intact had greater comprehension of sentences spoken with sentence prosody. For list prosody, participants with deficits in auditory executive control and/or short-term memory and the left angular gyrus and globus pallidus relatively intact, demonstrated better comprehension of sentences spoken with list prosody. Overall, the results from Experiment 2 indicate that following a left hemisphere stroke, individuals need good auditory attention and an intact left fronto-parietal network to benefit from typical sentence prosody, yet when cognitive deficits are present and this fronto-parietal network is damaged, list prosody may be more beneficial.
ContributorsLaCroix, Arianna (Author) / Rogalsky, Corianne (Thesis advisor) / Azuma, Tamiko (Committee member) / Braden, B. Blair (Committee member) / Liss, Julie (Committee member) / Arizona State University (Publisher)
Created2019
Description
An increasing number of veterans are transitioning from military service to college. Critical to academic success is the process of decision-making, which previous research has found to be influenced by a variety of factors including anxiety and working memory (WM). Many service-related conditions often influence anxiety and WM, and given the high prevalence of these conditions among veterans, the present study aimed to analyze the effects of working memory and anxiety on decision-making behavior in U.S. Military Veterans. Participants completed a large test battery including tasks assessing WM skills (Symmetry Span Task), anxiety (Beck Anxiety Inventory), and decision-making (Iowa Gambling Task). The study results indicated that WM and anxiety both play roles in decision-making performance in young military veterans. High anxiety is related to increased avoidance of adverse outcomes in decision-making for U.S. Military Veterans, while lower working memory span is associated with greater risk-taking behavior. This study provides both functional and clinical implications into areas of possible intervention that need to be assessed in military veterans, as well as modifications to these assessments that need to be made in order to appropriately measure decision-making behavior. Future work will be done in order to more effectively analyze the adverse impacts of service-related conditions and the ways in which intervention can be implemented in order to minimize these effects.
ContributorsTully, Mckayla Lynne (Author) / Azuma, Tamiko (Thesis director) / Gallagher, Karen (Committee member) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Department of Speech and Hearing Science (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
By providing vignettes with manipulated scientific evidence, this research examined if including more or less scientific detail affected decision-making in regards to the death penalty. Participants were randomly assigned one of the two manipulations (less science and more science) after reading a short scenario introducing the mock capital trial and their role as jury members. Survey respondents were told that a jury had previously found the defendant guilty and they would now deliberate the appropriate punishment. Before being exposed to the manipulation, respondents answered questions pertaining to their prior belief in the death penalty, as well as their level of support of procedural justice and science. These questions provided a baseline to compare to their sentencing decision. Participants were then asked what sentence they would impose \u2014 life in prison or death \u2014 and how the fMRI evidence presented by an expert witness for the defense affected their decision. Both quantitative and qualitative measures were used to identify how the level of scientific detail affected their decision. Our intended predictor variable (level of scientific detail) did not affect juror decision-making. In fact, the qualitative results revealed a variety of interpretations of the scientific evidence used both in favor of death and in favor of life. When looking at what did predict juror decision-making, gender, prior belief in the death penalty, and political ideology all were significant predictors. As in previous literature, the fMRI evidence in our study had mixed results with regards to implementation of the death penalty. This held true in both of our manipulations, showing that despite the level of detail in evidence intended for mitigation, jurors with preconceived notions may still disregard the evidence, and some jurors may even view it is aggravating and thus increase the likelihood of a death sentence for a defendant with such brain abnormalities.
ContributorsBerry, Megan Cheyenne (Author) / Fradella, Hank (Thesis director) / Pardini, Dustin (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
It has been suggested that directed forgetting (DF) in the item-method paradigm results from selective rehearsal of R items and passive decay of F items. However, recent evidence suggested that the passive decay explanation is insufficient. The current experiments examined two theories of DF that assume an active forgetting process: (1) attentional inhibition and (2) tagging and selective search (TSS). Across three experiments, the central tenets of these theories were evaluated. Experiment 1 included encoding manipulations in an attempt to distinguish between these competing theories, but the results were inconclusive. Experiments 2 and 3 examined the theories separately. The results from Experiment 2 supported a representation suppression account of attentional inhibition, while the evidence from Experiment 3 suggested that TSS was not a viable mechanism for DF. Overall, the results provide additional evidence that forgetting is due to an active process, and suggest this process may act to suppress the representations of F items.
ContributorsHansen, Whitney Anne (Author) / Goldinger, Stephen D. (Thesis advisor) / Azuma, Tamiko (Committee member) / Brewer, Gene (Committee member) / Homa, Donald (Committee member) / Arizona State University (Publisher)
Created2011
Description
The present study examined the effects that mild traumatic brain injury (mTBI) has on an individual’s episodic memory by looking at participants’ abilities to recall stories both immediately after being verbally told and after a delay. Thirty-seven participants were sorted into a control group (N=27) and a mTBI group (N=10) and then given the Wechsler Memory Scale’s two subtests, Logical Memory I and Logical Memory II. Logical Memory I consists of two verbally given stories in which the participant immediately retells the story to the assessor with as much detail and original vocabulary as they can remember. Logical Memory II has the participants, without prior knowledge, retell the same two stories after a thirty-minute delay. Once recorded, researchers transcribed and scored the participants’ story recalls, gathering data on what errors, correct ideas, and vocabulary the participants made and remembered. The data was then analyzed through an Analysis of Variance (ANOVA), looking at the interaction of Story (of the two stories that the participants were told), Group (whether mTBI or control) , and Delay (whether it was the immediate or delayed recall). Trends in the data show that participants with a history of mTBI do more poorly than the control group proving that memory is affected by acquired brain injury and that further studies to examine how and why this is the case are needed.
ContributorsAndrews, Chaley (Author) / Azuma, Tamiko (Thesis director) / Ratiu, Ileana (Committee member) / Barrett, The Honors College (Contributor) / College of Health Solutions (Contributor) / Sanford School of Social and Family Dynamics (Contributor)
Created2023-05
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