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Saccadic eye movements are guided by attention. Indeed, some saccade trajectory effects serve as an index the attentional strength of visual objects in the map of visual space used to plan a saccade. One approach to understanding saccade planning relies on simple tasks in sparse displays (containing a single target and distractor object) to develop neurophysiologically plausible models of saccade behavior. Under tightly controlled conditions, saccade trajectories can be well predicted by representing displays of objects with simple visual features and their relative salience. But the world in which the saccade system typically operates is not sparse, and observer eye movements are guided by more than just salience. As such, another approach has been to examine saccadic behavior in complex scenes and complicated goals. Such scene context can drastically affect saccades in ways that are not well predicted by a context-free and expectation-free representation of visual salience. This dissertation starts to bridge this gap between these literatures by focusing on object surfaces. Covert shifts of attention operate on representations informed not just by stimulus salience and location-based expectations, but also by the perceptual organization of object surfaces. Covert attention can be guided by surface context, such that targets and distractors are processed differently as a function of whether they are on the same or different surface. These effects are fragile, however, and have previously only been demonstrated in relatively engaging tasks and with strong perceptions of objecthood. The present work tested the strength of the relationship between attention and saccades by testing whether surface context guides orienting eye movements. Observers made saccades to objects that could be organized with different surface structure. In four experiments (Chapters 2 and 3) I found no evidence that the saccade map encoded surface context. But in two experiments (Chapters 4 and 5) I demonstrate saccade trajectories are sensitive to surface context, independently of low or high task engagement. This demonstrates that object surface-based representations are not necessarily fragile and can affect the oculomotor map even for simple saccadic orienting for which the surface is task-irrelevant. This lends evidence to the theory that the nature of the representation of vision is one of object surfaces, and suggests that the strength of object encoding is stronger than has been previously demonstrated.

The effectiveness of attention and working memory (A/WM) training programs in improving executive functions (EFs) is heavily debated. The objective of the current study was to evaluate the efficacy of a game-based process-specific cognitive intervention program (Dino Island; DI), on improving attention, working memory (WM), and pre-literacy skills in preschoolers. A secondary objective was to evaluate the feasibility of delivering DI intervention in community settings. Dino Island is an intervention program that consists of five hierarchically structured tasks that target attention and WM. The intervention also involves the teaching of metacognitive strategies to facilitate transfer effects to daily activities. The DI intervention was delivered to preschoolers (ages four to six years) during regular school days. Ten preschoolers were randomly assigned to either an active DI intervention group, or an educational games control group, with five participants in each group. All participants completed 12 hours of intervention over an eight to ten-week period. Children’s attention, EF and school readiness was assessed pre and post intervention using cognitive measures, rating scales and interviews. Non-parametric test results found significant changes in working memory for the DI intervention group (p = .03), however, results did not show significant gains in other abilities. A case study approach was then utilized to further explore outcomes for children in the DI intervention condition. The results suggest that DI training can potentially lead to gains in WM among preschool children, providing preliminary evidence of its efficacy within this age groups. DI is also feasible to be delivered within school settings during regular school hours. / Graduate

Much of the previous work investigating the influence of cholinergic tone on cortical circuits has emphasized global states of arousal and local circuit dynamics; however the cholinergic system is well-suited to coordinate large-scale cortical interactions due to its diffuse cortically projecting arborization and diverse influence on the various cell types within the cortical microcircuit. In this thesis I examined the function of cortical cholinergic tone in supporting long-range cortical interactions, feed-forward sensory signaling, and active processing of behaviorally relevant stimuli. I utilized optogenetic stimulation and silencing of the cholinergic nucleus basalis while recording from the auditory-prefrontal cortical circuit as well as performing local drug infusions in awake mice. I demonstrate that prefrontal cortex actively responds to cortico-cortical sensory input in animals passively presented with acoustic stimuli and that muscarinic receptor binding within auditory cortex is essential for feedforward pathways from auditory cortex to transmit sensory related neural signals. Specifically, muscarinic antagonists applied to the auditory cortex disrupt sensory signaling within auditory cortex as well as bottom up signaling to prefrontal cortex. Furthermore, muscarinic antagonists attenuated the influence of cortical cholinergic release on recording channels closest to drug infusion, confirming the efficacy of muscarinic antagonism, and demonstrating that aspects of cholinergic modulation are locally generated within cortical circuits, while others are globally generated in large networks. In task performing animals, I observed that optogenetic silencing of cholinergic nucleus basalis neurons attenuates the magnitude of prefrontal cortex alpha power following correct behavioral choice and that alpha in prefrontal and auditory cortical local field potentials are actively involved in behavioral learning during extinction, suggesting that cholinergic tone is involved in maintaining and updating the value of stimuli across behavioral trials. In summary, my thesis supports a model where endogenous cholinergic signaling is an essential component of normal auditory processing during low attentive states, contributes to circuit activation through local and large network mechanisms, and supports essential cortical dynamics that contribute to active behavioral processing of stimuli.

The main purpose of this series of studies was to investigate the efficacy of attentional coping strategies in altering children's responses to a painful experience. After a review of the theoretical and empirical links between pain experience and attention, Studies 1-4 compared the efficacy of imagery-based strategies that focussed attention away from a painful experience (distraction) or towards a painful experience (sensory-focussing) on 7- to 14-year-old children??s responses to cold-pressor pain. Image calibration studies (Studies 1-2) ensured that the imagery interventions were matched for other important parameters including affect and vividness. Studies 3 and 4 found that imagery-based attentional coping strategies led to increased tolerance of cold-pressor pain relative to a no-treatment control. Study 3 found that younger children (7-9 years) had better pain outcomes when assigned to the distraction condition than the sensory-focussing condition. For older children (10-14 years) the efficacy of different attentional interventions depended on the degree to which the strategy matched the child's preferred use of distraction as a coping style, providing partial support for the congruence hypothesis. Studies 5-6 tested the novel hypothesis that provision of sensory information before a painful experience may enhance the efficacy of an attentional coping strategy such as distraction. In line with self-regulation theory, children who received preparatory sensory information as well as a distraction intervention showed longer pain tolerance, lower pain intensity ratings, and a trend towards less facial pain expressions than if they received either intervention alone. These findings are discussed in terms of key attentional theories, and theories of attentional development. Implications for theory, clinical practice and further research are also considered.

Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 166-174). Also available for download via the World Wide Web; free to University of Oregon users.

Children with Autism Spectrum Disorders (ASDs) are impaired in visually disengaging attention in both social and non-social contexts, impairments that may, in subtler form, also affect the infant siblings of children with an ASD (ASD-sibs). I investigated patterns of visual attention (gazing) in six-month-old ASD-sibs (n = 17) and the siblings of typically developing children (COMP-sibs; n =17) during the Face-to-Face/Still-Face Protocol (FFSF). Also, I examined joint attention through the Early Social Communication Scales (ESCS) when ASD-sibs and COMP-sibs were eight months of age. The relationship between gazing and later joint attention was examined. Throughout the FFSF protocol, ASD-sibs shifted their gaze to and from their parents' faces less frequently than did COMP-sibs. The mean durations of ASD-sibs? gazes away from their parents' faces were longer than those of COMP-sibs. ASD-sibs and COMP-sibs did not differ in the mean durations of gazes at their parents' faces. Also, infants? shifts in gaze were positively correlated with initiating joint attention behaviors at eight months of age. In sum, ASD-sibs showed no deficits in visual interest to their parents? faces, but greater interest than COMP-sibs in non-face stimuli. Such differences may play an important role in the development of joint attention.

A great deal of research suggests that a close relationship with a teacher in preschool plays a significant role in promoting school readiness (Mashburn & Pianta, 2006). How exactly this relationship might impact children's acquisitions of skills, however, is not well understood. Strong theoretical arguments suggest both children's motivation and attention control as likely explanatory mechanisms in this association. These two learning-related behaviors have been described for preschoolers within the framework of Approaches to Learning as Competence Motivation and Attention/Persistence (McDermott, Leigh, & Perry, 2002). To test these variables as potential mediators, data were analyzed from 115 Head Start children scheduled to enter kindergarten the following year. Teachers completed a measure of teacher-child attachment in the fall, and a measure of Approaches to Learning in the winter. Children were directly assessed on school readiness at the end of the year. Regression analyses were conducted to test two mediation models. Results indicated Attention/Persistence but not Competence Motivation as a significant mediator in the association between teacher-child relationships in preschool and school readiness. Implications for intervention with low-income preschoolers are discussed.

Previous studies showed that emotional pictures capture attention. Further, this effect was decreased by manipulating spatial attention. In contrast, studies produced mixed findings for effects of perceptual load on attention to emotional pictures. Emotional pictures can be phobic or nonphobic. Because phobia might be an evolutionary adaption, it is possible that effects of phobic pictures on attention differ from effects of nonphobic emotional pictures. The present thesis aimed at investigating attention in spider phobia. Attention to emotional pictures was operationalized as event-related potentials (ERPs) (P1, early posterior negativity [EPN,] and late positive potential [LPP]). Two research questions were formulated. First, do phobic pictures evoke larger ERPs than what can be expected from arousal and valence? Second, are effects of spatial attention and perceptual load on ERPs the same for phobic and nonphobic emotional pictures? To investigate this, phobic and nonphobic negative pictures were presented to spider phobic and nonphobic participants. To determine effects of spatial attention on ERPs, participants were instructed to divert attention to a single letter that was presented in the periphery. To determine effects of perceptual load on ERPs, participants were instructed to perform a letter discrimination task on one, two, or three letters that were presented in the periphery. Study 1 showed enhanced LPP amplitudes to phobic pictures independent of arousal and valence. Further, this effect was present in both phobic and nonphobic participants. Study 2 showed that there was no effect of perceptual load on LPP to phobic pictures. Study 3 showed that spatial attention reduced LPP amplitudes, and to a similar extent for both phobic and nonphobic pictures. Further, perceptual load did not reduce EPN or LPP amplitudes to either phobic or nonphobic pictures. To conclude, the results suggest that phobic pictures evoke larger ERP amplitudes than nonphobic pictures. Still, ERPs to phobic and nonphobic pictures are moderated similarly by spatial attention and perceptual load. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 3: Manuscript.</p>

Fear is a central aspect in mammalian evolution, prompting escape from and avoidance of threat and dangers. Therefore, it is reasonable to believe that we have a well developed system to detect dangers and quickly respond to them. It has been shown that threatening information has an advantage in information processing; it seems to promote a rapid capture of selective attention and puts demand on processing resources. It has been suggested that the elicitation of fear occurs automatically, and that it is independent of and impenetrable to cognition. The idea with the present research is that fear processing is dependent on all concurrent internal or external processing demands. One visual search study (Study II) and two secondary task studies (Study I &amp; III) have been conducted to investigate if external or internal distraction can interfere with fear processing. In order to provoke fear responses, spider or snake fearful individuals have been exposed to pictures of their feared stimulus. The aim of Study II was to investigate if the selective attention to fear stimuli could be influenced by contextual factors, such as the nature of the distracting stimuli in a visual search. Study I and III aimed to investigate manipulation of resources allocated to fear stimuli. In Study I, task demand was used as the manipulation, and in Study III an internal cognitive directive was used. The results from these studies indicate that fear is susceptible to manipulation by both external and internal means. By changing circumstances in the surrounding or in the individuals’ internal states, responses to threatening stimuli can be altered. This means that processing of threatening stimuli is influenced by other concurrent processing demands, suggesting that a fear response is not occurring as an isolated and impenetrable process. In an evolutionary perspective, a fear system that is easily triggered but has access to cognitive evaluation at all times ought to be far more flexible, thus creating a better chance for survival than a modular and impenetrable fear system.