The present study examined the impact of posttraumatic stress symptoms (PTSS) on adults’ ability to discriminate between various facial expressions of emotions. Additionally, the study examined whether individuals reporting PTSS exhibited an attentional bias toward threat-related facial expressions of emotions. The research design was a 2 (expression intensity) x 3 (emotional pairing) x 2 (PTSS group) mixed-model factorial design. Participants for the study were 89 undergraduates recruited from psychology courses at Western Kentucky University. Participants completed the Traumatic Stress Schedule to assess for prior exposure to traumatic events. A median split was used to divide the sample into two groups (i.e., low and high PTSS). Additionally, participants also completed a demographics questionnaire, the Impact of Events Scale-Revised, the Center for Epidemiological Studies Depression Scale, and the Depression Anxiety Stress Scales to assess for possible covariates. Then, participants completed the discrimination of facial expressions task and the dot probe position task. Results indicate that individuals experiencing high levels of PTSS have difficulty discriminating between threatening and non-threatening facial expressions of emotions; additionally, these individuals’ difficulty is exacerbated by comorbid levels of anxiety symptoms. Furthermore, results suggests these individuals focus attention on threatening facial expressions while avoiding expressions that may activate memories associated with the prior trauma. These findings have significant clinical implications, as clinicians could focus treatment on correcting these difficulties which should help promote more beneficial social interactions for these individuals experiencing high levels of PTSS. Additionally, these behavioral measures could be used to assess the effectiveness of treatment. Effective treatment should help alleviate these difficulties, which could be measured by improved performance on the discrimination of facial expressions task and the dot probe position task from baseline to post-treatment.

Numerous studies have looked at cognitive processing, more specifically attention, and its important role in various dynamic and static movements. Research on attentional demands in sport is an expanding area with studies now being done on athletes revealing the role of cognitive factors in the execution of motor movements in sports. Objective: the purpose of this study was to determine the attentional demands of a delivery in curling using a classic probe technique with a verbal response time and by measuring numerous performance variables. Subjects: ten healthy skilled curling players and nine healthy novice curling players undertook an auditory probe reaction time concurrently with a delivery in curling. Method: Sixty shots were executed with ten shots for each of the three phases of the shot, in all 30 take outs and 30 draws were done by each participant. The first phase when the player comes out of the “hack”, the second phase of the throw was when the player slid across the “t-line”. The third phase is when the player arrives near the line of Hog and releases the stone. Results: results revealed that reaction times were longer at phase 1 of the delivery for all subjects. The attentional demands for the draw and take out were highest at the phase one of the delivery, furthermore, compared to the draw, a significant rise of RT was seen in phase 3 of the take out shot. Significant differences were also found between the two experimental groups, with the most notable ones being that expert had a better shot success and a slower delivery time than the novice group. Conclusion: These results will lead to a better understanding of the attentional demands of two key shots in the sport of Curling and help curling coaches and teachers, as well as the players of the sport to know more about the attentional demands of the execution movement of the sport. This study also opens a new and interesting perspective on the importance of attention while performing motor tasks that are more complex and demanding.

Since antiquity, philosophers, theologians, and scientists have been interested in human memory; however, researchers today are still working to understand the capabilities, boundaries, and architecture. While the storage capabilities of long-term memory are seemingly unlimited (Bahrick, 1984), working memory, or the ability to maintain and manipulate information held in memory, seems to have stringent capacity limits (e.g., Cowan, 2001). Individual differences, however, do exist and these differences can often predict performance on a wide variety of tasks (cf. Engle, 2001). Recently, researchers have promoted the enticing possibility that simple behavioral training can expand the limits of working memory which indeed may also lead to improvements on other cognitive processes as well (cf. Morrison&Chein, 2011). The current study investigated this possibility. Recommendations from the skill training literature (cf. Schneider, 1985) were incorporated to create optimized verbal and spatial working memory training tasks. Significant performance improvements were evident across eight days of cognitive training using verbal and spatial adaptive n-back procedures. Training-related improvements were also evident for some untrained measures of visual short-term memory, attentional control, and working memory. These training effects, however, were not universal. Other measures of visual short-term memory and attentional control, as well as measures of fluid intelligence were unaffected by training.

Several decades of physiology, imaging and psychophysics research on attention has generated an enormous amount of data describing myriad forms of attentional effects. A similar breadth of theoretical models have been proposed that attempt to explain these effects in varying amounts of detail. However, there remains a need for neurally detailed mechanistic models of attention that connect more directly with various kinds of experimental data -- behavioural, psychophysical, neurophysiological, and neuroanatomical -- and that provide experimentally testable predictions. Research has been conducted that aims to identify neurally consistent principles that underlie selective attentional processing in cortex. The research specifically focuses on describing the functional mechanisms of attentional routing in a large-scale hierarchical model, and demonstrating the biological plausibility of the model by presenting a spiking neuron implementation that can account for a variety of attentional effects. The thesis begins by discussing several significant physiological effects of attention, and prominent brain areas involved in selective attention, which provide strong constraints for developing a model of attentional processing in cortex. Several prominent models of attention are then discussed, from which a set of common limitations in existing models is assembled that need to be addressed by the proposed model. One central limitation is that, for many existing models, it remains to be demonstrated that their computations can be plausibly performed in spiking neurons. Further, few models address attentional effects for more than a single neuron or single cortical area. And finally, few are able to account for different forms of attentional modulation in a single detailed model. These and other limitations are addressed by the Attentional Routing Circuit (ARC) proposed in this thesis. The presentation of the ARC begins with the proposal of a high-level mathematical model for selective routing in the visual hierarchy. The mathematical model is used to demonstrate that the suggested mechanisms allow for scale- and position-invariant representations of attended stimuli to be formed, and provides a functional context for interpreting detailed physiological effects. To evaluate the model's biological plausibility, the Neural Engineering Framework (NEF) is used to implement the ARC as a detailed spiking neuron model. Simulation results are then presented which demonstrate that selective routing can be performed efficiently in spiking neurons in a way that is consistent with the mathematical model. The neural circuitry for computing and applying attentional control signals in the ARC is then mapped on to neural populations in specific cortical laminae using known anatomical interlaminar and interareal connections to support the plausibility of its cortical implementation. The model is then tested for its ability to account for several forms of attentional modulation that have been reported in neurophysiological experiments. Three experiments of attention in macaque are simulated using the ARC, and for each of these experiments, the model is shown to be quantitatively consistent with measured data. Specifically, a study by Womelsdorf et al. (2008) demonstrates that spatial shifts of attention result in a shifting and shrinking of receptive fields depending on the target's position. An experiment by Treue and Martinez-Trujllo (1999) reports that attentional shifts between receptive field stimuli produce a multiplicative scaling of responses, but do not affect the neural tuning sensitivity. Finally, a study by Lee and Maunsell (2010) demonstrates that attentional shifts result in a multiplicative scaling of neural contrast-response functions that is consistent with a response-gain effect. The model accounts for each of these experimentally observed attentional effects using a single mechanism for selectively processing attended stimuli. In conclusion, it is suggested that the ARC is distinguished from previous models by providing a unifying interpretation of attentional effects at the level of single cells, neural populations, cortical areas, and over the bulk of the visual hierarchy. As well, there are several advantages of the ARC over previous models, including: (1) scalability to larger implementations without affecting the model's principles; (2) a significant increase in biological plausibility; (3) the ability to account for experimental results at multiple levels of analysis; (4) a detailed description of the model's anatomical substrate; (5) the ability to perform selective routing while preserving biological detail; and (6) generating a variety of experimentally testable predictions.

In this study the mechanisms that control attention in natural scenes was examined. It was explored whether familiarity with the environment makes participants more sensitive to changes or novel events in the scene. Previous investigation of this issue has been based on viewing 2D pictures/images of simple objects or of natural scenes, a situation which does not accurately reflect the challenges of natural vision. In order to examine this issue, as well as the differences between 2D and 3D environments, two experiments were designed in which the general task demands could be manipulated. The results revealed that familiarity with the environment significantly increased the time spent fixating regions in the scene where a change had occurred. The results support the hypothesis that we learn the structure of natural scenes over time, and that attention is attracted by deviations from the stored scene representation. Such a mechanism would allow attention to objects or events that were not explicitly on the current cognitive agenda.

Alcohol research has shown that alcohol-related stimuli can disrupt behavioral control and attract more attention in alcohol drinkers. Stimuli typically used in tasks assessing these mechanisms are likely representative of an individual's history. Responses to visual stimuli that no longer closely resemble an individual's history may help shed light on whether these behaviors are due to classical conditioning or processes such as semantic priming. Hypotheses were tested using typical visual stimuli and modified, abstract versions in these tasks. 41 participants were exposed to these stimuli types while using a visual dot probe task. The difference in degree of attentional bias between real and modified stimuli was determined using gaze time. Individuals participated in two versions of the attentional bias-behavioral activation (ABBA) task. Proportion of inhibitory failure differences between versions was examined for the effects of stimuli modification on behavioral control. Results demonstrated that the sample did not exhibit an attentional bias to alcohol. Visual probe results yielded no differences between real and modified stimuli on attentional bias. ABBA performance indicated no differences as a result of image abstraction or stimuli type. Reasons for these findings and comparisons to similar research inquiries using the tasks the current thesis utilized were explored.

One unresolved issue in early word learning research is the relationship between word learning, categorization, and attention. Two distinct cognitive processes, attentional preferences related to categorical processing and inter-modal matching are involved in this relationship. Keeping the effects of these processes separate and controlled can be a difficult task. Not doing so can potentially confound the interpretation of research in this area. In a series of four preferential looking studies, the effects of referential assignment and novelty seeking in infancy were teased apart. In Study 1, 13-month olds preferred to look toward a monitor on which the stimuli changed category on every trial, and away from a monitor on which the stimuli were drawn from a single category. This preference developed in conditions in which infants listened to labels, non-language sound, or participated in silence. In Study 2, 18-month-olds developed the same preference when listening to non-language sounds or when participating in silence, but developed no preference when listening to labels. Results of studies 3 and 4 suggest that the lack of preference by 18-month-olds in the label condition result from competing behaviors of novelty seeking and referential assignment. / text

Despite the large volume of research on tobacco withdrawal, the vast majority of studies have focused on the onset and remission of symptoms over the course of several days and weeks, with the earliest assessment periods occurring the day after cessation. To date, there has been no systematic study of the very early time course of the tobacco withdrawal syndrome, despite its obvious relevance to the maintenance of both smoking and postcessation abstinence. The published literature contains a range of estimates about the early appearance of withdrawal symptoms, but without reference to empirical data. The main objective of the current study was to conduct a comprehensive, multimodal assessment of the early time course of the symptoms associated with smoking withdrawal among cigarette smokers. Participants were 50 smokers randomly assigned to either abstain or smoke at their own pace during four hours in the laboratory. Dependent measures included a physiological measure (resting heart rate); sustained attention (the Rapid Visual Information Processing task; RVIP); selective attention to smoking stimuli (an emotional Stroop task); and self-report (the Wisconsin Smoking Withdrawal Scales; WSWS). After baseline assessment, participants were assigned to the two conditions and the dependent measures were collected every 30 minutes. Generalized Estimating Equations (GEEs) revealed that abstinent participants displayed greater withdrawal than continuing smokers on all measures with the exception of the Stroop task. Statistically significant differences in withdrawal were found within 60 minutes on heart rate, within 30 minutes on the RVIP, and between 30 minutes and 180 minutes postcessation on the various subscales of the WSWS. These findings provide the first evidence of the early time course of tobacco withdrawal symptoms, although further research is needed to distinguish withdrawal effects from drug offset effects. Implications for the understandi ng the maintenance of daily smoking and for the treatment of tobacco dependence are discussed.

The aim of this study was to come to a better understanding of possible neuropsychological mechanisms underlying psychosocial well-being and therefore to determine whether a relationship between neuropsychological executive functions and psychosocial well-being does indeed exist. Research was conducted in the domains of neuropsychology and positive psychology. This thesis consists of three articles, namely I ) Neuropsychological executive functions and psychosocial well-being: A review, 2) Attentional switching and psychosocial! well-being, and 3) The relationship between generativity as neuropsychological process and psychosocial well-being. The first article argued the possibility of a relationship between neuropsychological and psychosocial aspects, with reference to a pluralistic ecosystems perspective, neuropsychological and other positive psychological theories, such as Miller's neuropsychodynamic model and Frederickson's broaden-and-build theory, as well as existing empirical studies. Numerous neuropsychological studies have indicated that the prefrontal cortex is involved in executive functions, with its main function to regulate both cognitive and affective functioning. Analyses of existing empirical studies indicated an established relationship between prefrontal lobe / executive / regulatory dysfunction and psychopathology, but also that the relationship between normal or optimal prefrontal executive functions and psychosocial well-being is still unclear. The first article concluded that evidence correlating neuropsychological functioning with human flourishing, or indicating possible neuropsychological mechanisms involved in psychosocial well-being, is sparse, presenting a serious lacuna in scientific knowledge. The following two articles focused on contributing to filling this lacuna. "Attentional switching and psychosocial well-being" and "The relationship between generativity, as neuropsychological process and psychosocial well-being" focused on attentional switching and generativity, as part of neuropsychological executive functions, as potential mechanisms associated with psychosocial well-being. These studies aimed to determine whether the capacity to switch attention, as measured by the Color Trails Test (CTT) and Wisconsin Card Sorting Test (WCST), and the capacity to generate novelty, as measured by the Controlled Verbal Fluency Task (CVFT) (Benton, 1967) and Uses of Objects Test (UOT) (Getzels & Jackson, 1962), are related to the degree of psychosocial well-being experienced. As part of the interdisciplinary POWIRS (Profiles of Obese Women with Insulin Resistance Syndrome) project, black African women (article 2 n=66; article 3 n=72) completed the above mentioned neuropsychological measures, as well as indices of psychosocial wellbeing, in a cross-sectional design. The psychosocial measures included the Affectometer (AFM) 2 (Kammann & Flett, 1983); Constructive Thinking Inventory (CTI) abbreviated version (Epstein & Meier, 1989); Sense of Coherence Scale (SOC- 29) (Antonovsky, 1987, 1993); The Fortitude Questionnaire (FORQ) (Pretorius, 1998); JAREL Spiritual Well-being Scale (SWS-H) (Hungelman et al., 1989); Psychological Well-being Scales (SPW-B) (Ryff & Singer, 1998); and the Cognitive Appraisal Questionnaire (CAQ) (Botha & Wissing, 2003). The main findings of these studies were hat the ease of attentional switching and generativity correlates statistically (p<0.5) and practically significantly with higher levels of psychosocial well-being. From a micro-deterministic perspective it can be concluded that frontal lobe executive functions may play a role in the regulation higher-order adjusting psychosocial functions related to quality of life. From a micro-deterministic perspective it can be concluded that psychosocial well-being, while being influenced by executive functions, may also influence the continuous development of neuropsychological executive functions. / Thesis (Ph.D. (Psychology))--North-West University, Potchefstroom Campus, 2005.

Selective attention may be an effective strategy for regulating emotions. The current study measured selective attention to emotional pictures in healthy adults using a novel computerized task. Participants saw pictorial cues on the right or left of the screen, followed by target words on the same or opposite side. Participants were divided into two groups. The suppress group had to avoid looking at pictures (cues), whereas the attend group had to look at them. Both groups categorized targets as indoor or outdoor words. Subsequent cue/target recognition tests were administered. Performance on both tasks was assessed by picture valence, revealing reduced inhibitory control to negative picture and difficulties reorienting to negatively cued locations. These findings contribute to our understanding of affective-attentional interactions in healthy adults. Moreover, the apparent inability to avoid looking at negative items may highlight a need to explore other emotion regulation techniques.