Attentional Blink and Top-Down Directives in Alzheimer's Disease and Aging
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It is not well understood why patients with Alzheimer's disease (AD) have difficulty attending to relevant information in their environment. Deficits in top-down processing (such as difficulty using prior instruction or category identification to direct attention) or limitations in coping with rapid temporal demands maybe possible explanations for this impairment. This study was design to address attention deficits using the attentional blink paradigm that can dissociate top-down directives from rapid temporal demands. The attentional blink occurs when two stimuli (S1 and S2) are presented in rapid succession and the accurate identification of the second stimulus (S2) is reduced if it is presented very shortly after the first (S1). The accuracy of S2 was compared in patients with AD, age-matched healthy controls and younger healthy controls. We hypothesized that aging would affect the ability to keep pace with rapid presentations, but patients with AD would have additional deficits in top-down directives. Results showed that younger and older controls could utilize top-down instructions to improve their accuracy, but older controls could only improve their performance with sufficient time between stimuli presentation. This confirmed our hypothesis of age-related slowing. Accuracy in the AD group was lower overall than either healthy groups but importantly, performance was the same whether or not a priori instructions were provided. This supports our hypothesis that patients with AD are not able to utilize top-down directives. Results are discussed in the context of theories related to limited attentional resources and inhibition.
Eat At Mom's: Critiquing and Rebuilding The Breastfeeding Paradigm
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For the past three decades breastfeeding has been globally promoted as the ideal method of infant feeding with policy makers defining breastfeeding and shaping the current breastfeeding paradigm with their recommendations that often leave out the voices of nursing women. We believe that the voices of mothers and their infants can be a valuable source of information to balance this discrepancy and offer suggestions to changing the current model of breastfeeding education to better match their specific needs. One hundred and twenty-seven first time mothers (FTM) committed to breastfeeding were recruited from popular online communities that focus on pregnancy and parenting for a multi-method study on breastfeeding views. Participants completed a series of quantitative measures consisting of the Iowa Infant Feeding Assessment Scale, Ways of Knowing Inventory, and Maternal Breastfeeding Evaluation Scale that focused on maternal infant feeding preference, learning styles, and maternal breastfeeding satisfaction. In addition, a variety of open-ended questions regarding prenatal breastfeeding beliefs and postpartum realities were used to identify changes that occurred as women negotiated from pregnancy to the early and late postpartum periods. Repeated measures ANOVA indicated significant differences in the silence and subjective dimensions of the Ways of Knowing Inventory indicating that as time passed, women were less likely to feel as though they had no voice in matters concerning breastfeeding their infants, F (2, 142) = 3.21, p < .05 and more apt to realize the value of their intuitive powers and believe that the truth could reside from within as opposed to relying on outside authorities, F (2, 142) = 4.98, p < .01. Critical discourse analysis revealed power struggles between FTMs and hospital personnel whose actions often undermined maternal efforts. Infant responses to feeding method were found to play a pivotal role in breastfeeding outcome suggesting a bilateral decision making process. Mothers also preferred individualized care as opposed to generalized instructions. The adequacy of the current breastfeeding paradigm will be discussed with suggestions on how to restructure current breastfeeding education to be more focused on the unique needs of women and their infants.
The Interpersonal Foundations of Anti-Atheist Prejudice
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Anti-atheist prejudice in the U.S. is socially accepted and rife--and not just because most Americans are religious. This research suggests that hostility toward atheists is related in part to protecting parental relationships. To the extent that they are established within parental relationships, shared reality theory implies that religious beliefs and associated attitudes will be psychologically defended to the extent that the parental relationships engaged are strong, healthy, and vital (Magee & Hardin, 2010; see also Hardin & Higgins, 1996). Three experiments examined the regulation of anti-atheist prejudice in the defense and protection of religious shared realities with parents, as implied by shared reality theory, and used parental attachment as an indicator of the strength and vitality of the parental relationship. The first two experiments explored parental attachment in the regulation of automatic anti-atheist prejudice during social interactions. In Experiment 1, automatic attitudes toward atheists were assessed with a subliminal sequential priming task in a social tuning paradigm in which the experimenter casually mentioned he was an atheist, or did not (e.g., Lowery et al., 2001). Interacting with an atheist reduced automatic anti-atheist prejudice among those with low parental attachment and, if anything, increased automatic anti-atheist prejudice among those with high parental attachment. Experiment 2 tested the causal role of parental attachment by experimentally manipulating parental attachment with an essay task and found complementary results: Interacting with an atheist reduced automatic anti-atheist prejudice among those with low manipulated parental attachment, increased automatic anti-atheist prejudice among those with high manipulated parental attachment, and did not affect automatic anti-atheist prejudice among those in a non-parental salience comparison condition. Experiment 3 manipulated the mere cognitive salience of the concept `atheist' (in the absence of relationship demands) via a subliminal prime word task. Subliminal exposure to the word atheist reduced explicit anti-atheist prejudice among those with low parental attachment and low parental religious shared reality, but not among those with high parental attachment or high parental religious shared reality. This research suggests that when religious people interact with atheists (or think about atheists) anti-atheist prejudice is activated and then regulated by parental attachment.
Fructose-Conditioned Flavor-Flavor Preferences in the Rat: Role of Dopaminergic Receptor Subtypes in the Nucleus Accumbens, Amygdala, and Medial Prefrontal Cortex
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Fructose-Conditioned Flavor-Flavor Preferences in the Rat: Role of Dopaminergic Receptor Subtypes in the Nucleus Accumbens, Amygdala, and Medial Prefrontal Cortex by Danielle C. Malkusz Systemic administration of dopamine (DA) D1 (SCH23390) and D2 (raclopride) antagonists blocked both acquisition and expression of fructose-conditioned flavor preferences (CFP). It is unclear what brain circuits are involved in mediating these effects. The present study investigated DA signaling within the nucleus accumbens shell (NAC), amygdala (AMY) and medial prefrontal cortex (mPFC) in the acquisition and expression of fructose-CFP. In Experiment 1, separate groups of rats were injected daily in the NAC or AMY with saline, SCH23390 (24 nmol) or raclopride (24 nmol) prior to training sessions with a flavor (CS+) mixed with 8% fructose and 0.2% saccharin (CS+/F) and a different flavor (CS-) mixed with only 0.2% saccharin. In two-bottle choice tests with the CS+ or CS- flavor presented in a 0.2% saccharin solution, only rats injected with raclopride in the AMY failed to acquire a CS+ preference (45-54%). In Experiment 2, new rats were identically trained, but saline, SCH23390 and raclopride were injected in the mPFC. In subsequent two-bottle choice tests, SCH23390 -and raclopride -treated rats failed to exhibit a CS+ preference (50-56%). In Experiment 3, new rats were trained with CS+/F and CS-without injections. Subsequent two-bottle choice tests were then conducted following bilateral injections of SCH23390 or raclopride in the mPFC at total doses of 12, 24 and 48 nmol. Expression of the CS+ preference failed to be affected by either antagonist, indicating that the mPFC is not involved in the maintenance of this preference. These data indicate that the acquisition of fructose-CFP is dependent on DA signaling in the mPFC and AMY.
How Childhood Obesity Predicts Academic Achievement: A Longitudinal Study
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Improvements in academic achievement have been linked to childhood obesity indices such as greater physical activity (PA) and lower Body Mass Index (BMI). Yet, little is known about the mechanisms through which childhood obesity indices predict academic achievement. The present study tested whether the influence of PA and BMI on academic achievement is mediated by several cognitive and emotional processes that have been shown in past studies to have independent effects: executive functioning, concentration, and internalizing symptoms. This study also tested the antecedent role of SES on indices of childhood obesity and academic achievement. Data from the 1991-2007 National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were used to analyze a sample of over 1000 U.S. children from ages 9 to 15. Path model parameters were estimated using Linear Mixed Models. The hypothesized meditational model was supported by childhood obesity indices predicting both reading and math achievement through cognitive processes (executive functioning and concentration) but not emotional processes (internalizing symptoms). Specifically, greater PA led to lower BMI which, in turn, predicted higher executive functioning performance, higher concentration levels, and then improved academic achievement in reading and math from ages 9 to 15. The results of this study may inform the development of school-based interventions and policy approaches to prevent childhood obesity.
The Effect of Type of Feedback on Human Timing Performance
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The purpose of the present experiment was to assess the effects of several of forms of feedback on timing performance across a range of durations (range: 5-25 s) under conditions in which participants were required to perform a concurrent task. Type of feedback was characterized in terms of precision, a term adopted to describe the quantitative relation between properties of a given feedback stimulus with properties of the timing response. Two models for describing the precision of feedback stimuli were proposed. In the present experiment, 4 different forms of feedback that varied in level of precision in relation to estimated time and stimulus duration were employed in a between-groups design. Analyses of the log-transformed data suggested that various forms of feedback differentially affected time judgments, indicating a relation between the between precision of feedback and time judgments; greater precision yielded more accurate judgments. One of the two proposed models of feedback precision was better supported by the data. According to that model, precision of feedback increases in direct relation to the number of feedback statements contained within the feedback stimulus.
Regional Brain Asymmetries During Verbal and Spatial Tasks in Depression with High or Low Trait Anxiety
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Depression is a common disorder with various clinical presentations and is frequently comorbid with anxiety disorders. The relationship of regional brain asymmetry to mood disorders has been informed by neuropsychological models in which emotion is lateralized along positive/negative and approach/withdrawal dimensions and by clinical reports of affective disturbances following localized brain damage. Studies of regional hemispheric asymmetries point to relatively less activity in left frontal and right posterior regions in depression. Anxiety has also been associated with less left frontal, but increased right posterior activity, which has been related to arousal and may, in anxious-depressed individuals, offset the posterior asymmetry normally seen in depression. These asymmetries have been indexed by EEG or inferred through the use of lateralized auditory and visual tasks (e.g., dichotic listening and chimeric face tasks). However, associations between regional EEG activity and neurocognitive function in depression or anxiety remain unclear. A number of neurocognitive deficits have been associated with depression, including poorer spatial than verbal skills, supporting right posterior deficits. The present study used matched verbal (Word Finding) and spatial (Dot Localization) tasks to compare task-related alpha asymmetries in depressed patients grouped according to level of trait anxiety. EEG was recorded from depressed patients with high anxiety (n=14) or low anxiety (n=14) and 21 age- and education-matched healthy adults during the two tasks, and alpha power was averaged within each task. Task performance was also recorded. As predicted, the two patient groups exhibited opposite patterns of regional hemispheric alpha asymmetry. Greater right than left central-parietal activation was seen in the high-anxiety depressed group during the spatial task, whereas the verbal task elicited greater left than right frontal-central activation in the low-anxiety depressed group. Additionally, low-anxiety depressed patients and controls performed better on the verbal than the spatial task, whereas there was no asymmetry of performance within the high-anxiety depressed group. These results are consistent with Heller's two-dimensional model of depression and anxiety and highlight the sensitivity of task-related alpha in discriminating among subgroups of depressed patients differing in trait anxiety.
Eye Movement Desensitization Reprocessing: The Linguistic Analysis of a Treatment of Posttraumatic Stress Disorder in a Soldier
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An attempt was made in this case study to assess the Referential Process, a set of phases that illustrate the process of how individuals place words upon conscious and unconscious non-verbal experiences, in an EMDR treatment of a veteran. The Referential Process was assessed by shifts in scores of three measures, Referential Activity (WRAD), Reflection, and Disfluency, as captured by a computerized linguistic program. The shifts among the measures were used to guide a qualitative description of the process in an effective treatment of a veteran with PTSD. This is the first study to examine levels of referential activity and the referential process in an EMDR treatment and more generally referential activity in any trauma focused treatment. Additionally, whereas most EMDR studies have focused upon one trauma incident, this study adds to the growing, but limited, literature of EMDR treatment in the military population with numerous trauma memories. With the two objectives in mind, the recorded sessions were transcribed and coded and a computerized linguistic and qualitative analysis was applied to 10 sessions of a 12 session EMDR treatment. The patient exhibited high referential activity as measured by WRAD levels, when compared to other psychotherapy samples, which indicates that he was immersed in the narrative for much of the treatment. The high WRAD levels may be attributed to the treatment task of EMDR. An examination of the high WRAD narratives suggests that the WRAD measure may require further examination in trauma populations to decipher if the speaker is immersed in or reliving the narrative. The interaction between WRAD and Reflection in the Referential Process appears important in trauma processing and may relate to the significance of distancing (versus reliving) fostered by the EMDR protocol. The qualitative analysis revealed shifts in the veteran's schema as depicted by changes in: the therapeutic relationship, his negative cognitions about himself and patient reports of relationship with others.
Concept Mediation in the Adult Language Learner
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The purpose of the present research was to investigate the time course of lexical and conceptual development in the adult language learner. A review of the literature indicates that there is still no definitive model that encapsulates all degrees of bilingualism, including the adult language learner. One model, the revised hierarchical model (RHM) proposed by Kroll and Stewart (1994) has a developmental component that attempts to explain why memory is represented differently in the less fluent (beginning) bilingual speaker. Since its inception the predictions of the RHM have been challenged. Three novel experiments were presented and their results reviewed with regards to the predictions of the RHM. Several factors (i.e., orthography, phonology) were identified as being either facilitative or inhibitory to successful language learning. In Experiment 1, using a bilingual Russian-English Stroop task, language dominance (i.e., greater usage) rather than language proficiency (i.e., knowledge) was found to be a better predictor of performance for the fluent native Russian speakers. Moreover, while lexical and conceptual development appeared to be asymmetrical for the native English speakers, the results were moderated by orthography and phonology for these novice (i.e., non-Russian) language learners. To further investigate the effects of orthography and phonology on language learning, new stimuli and a novel training paradigm were introduced in Experiments 2 and 3. In both experiments, a modified Russian-English (using Romanized transliterations instead of Cyrillic script) version of the Stroop color-word interference task was used. Native English speakers were trained with and then tested on transliterated Russian and English color words. Verbal responses in both English and Russian were required. Experiment 3 extended the findings of Experiment 2 by adding a nonverbal (i.e., key press) condition. Results from both Experiments 2 and 3 suggest that access to conceptual representations in a second language are available early on during the language learning process; moreover, the influence of orthography, phonology and the language-learning environment appear to be important determinants in language learning. Implications for models of visual word processing and bilingual memory are discussed as they relate to second language learning and the dynamic nature of bilingualism.
The Long Arm/Shadow of Moral Exclusion: Parole and Reentry for People Convicted of Violent Offenses in New York State
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Abstract The trio of studies that comprise this dissertation emerged during a critical time in New York State when parole denials, sentence length, time served, and time on parole all increased in the name of public safety. Of particular interest were several policies that restricted, or eliminated altogether, the chance of parole for people convicted of violent offenses. While public safety served as the basis for these policies, the findings of Study 1 suggest that people convicted of violent crimes actually have extremely low recidivism rates and the lowest of all crime categories. Furthermore, recidivism was more likely due to technical violations than new crimes; and, new crimes were overwhelmingly non-violent in nature. No significant difference was found for return rates before and after these polices were implemented. Therefore, the data do not support a public safety gain from these policies. Study 2, based on 34 interviews with men and women convicted of crimes of violence, reveals moral exclusion within the parole process inside prison, prison life, and the reentry process (including parole supervision after release). Further, this study suggests a model for studying, and understanding, moral exclusion/inclusion from the perspective of `the excluded,' across six categories: visibility, acceptance, liberty/justice, basic resources, financial resources, and emotional resources/support. Additionally, social science evidence of transformation, remorse, and responsibility are offered in terms of catalysts and hurdles to transformation; four ways that responsibility is `carried' by people convicted of violent crimes; how transformation, remorse, and responsibility are expressed; and finally, mechanisms that sustain all three inside and outside of prison. This study also offers three new terms to the language of moral exclusion that provide nuance to the process of exclusion: provisional belonging, moral exclusion by contamination, and vicarious inclusion. Finally, Study 3 sheds light on the decision-making process through interviews with five former parole board commissioners, offering insight into how decisions are made, the criteria considered, and how social science research can (and does) inform the entire process. Implications of the three studies, including recommendations for changes to policies and practices affecting people convicted of violent crimes, are discussed.