<p> Many individuals rely on a navigational system every day to direct them to various destinations, and with the prevalence and danger of distracted driving accidents, it is imperative that we find an effective way to display navigational information to drivers with minimal visual distraction. The lane change test (LCT) was used to measure driving performance, as participants followed lane change cues presented on Road-Signs, a Head-Up Display (HUD), and a Head-Down Display (HDD). A peripheral detection task (PDT) was also implemented on half of the test tracks, with inward moving stimuli from either side of the road, to measure the participants&rsquo; ability to detect ecologically-valid stimuli while interacting with the assorted display locations. Driving performance, measured by the mean deviations from a normative path (MDev), was the worst with the HDD and similar with the Road-Signs and HUD. Analyses were completed to investigate a potential effect of age on the ability to interact with the display locations. Younger participants (20-24 years) performed the best with the HUD; while Older participants (26-31 years) performed the best with the Road-Signs. These differences are potentially attributed to the evolution of GPS technologies over the last decade. No significant differences were found in peripheral detection response time or accuracy between the display types or the age groups. As road signs cannot offer specific navigational instructions for all drivers in real-time, HUDs may be a good alternative to the in-vehicle HDD present in modern vehicles, but any in-vehicle interface implementation should be customizable and optional.</p><p>

<p> Research with human participants involves a complex combination of procedural elements in order to establish internal, external and measurement validity. Examining the accuracy of research equipment and methods that elicit similar behaviors as the general public is difficult. This research used driving as a model to address elements in the procedures that participants experience to elicit realistic behaviors. </p><p> An instrumented vehicle (IV) and driving simulator (SIM) measured experimental behaviors for average approach speed (in the 20m before the legal stop line); lateral distance from curb at 20m; lateral distance from curb at legal stop line (0m) and the stopping location (distance before or after 0m); and, compared with measured general driving public behaviors at stop-controlled intersections. The linear mixed effect analyses combined two experiments. In both, surveys were administered to gather driver&rsquo;s trait anxiety, driving anxiety and social desirability scores. Experiment One drivers (36% female) were grouped as Novice (5, 16-17 year olds who just obtained driving license), Young (4, 16-17 year olds who obtained license over a year ago) and Adult (5, 30-55 year olds licensed near age 16). Experiment Two drivers (47 SIM, 44 IV; 35% female) were College age (18-21 year olds licensed near age 16) and exposed to 1 of 16 different combinations (one of those treatments matched Experiment One&rsquo;s procedure) of procedural changes for: researcher attire (casual or formal), researcher proximity (control room, front or rear passenger seat), mode of instruction delivery (spoken, read or video) and hypothesis statement (none or explicit). At the end of Experiment Two, participants&rsquo; understanding of the experiment was coded into three debriefing variables. </p><p> Absolute behavioral validity of the IV to public behavior was achieved in one treatment (formal, front seat, spoken and no hypothesis) and including the debriefing variables in the model; no SIM combination achieved this. Trait anxiety scores appeared to explain behaviors in the IV or SIM and improved result interpretation as interactions with other independent variables. For improved research methods, it is recommended that coded debriefing variables, specific procedural elements, and trait anxiety scores be included and used to explain interactions or differences in participant behaviors. </p>

Thesis (doctoral)--University of Reading, 1999. / BLDSC reference no.: DX208656.

<p> The field of petrochemical refining could prevent incidents and improve processes through the application of measures of Situation Awareness (SA). Currently there are multiple measures of SA, with the Situation Awareness Global Assessment Technique (SAGAT) and the Situation Present Assessment Method (SPAM) being the most promising based on a number of theoretical and objective assessments. As researchers seek to apply measures of SA to the field of petrochemical refining, they will need more information on the applicability of these measures. To this end, this research sought to examine specific objective qualities of SAGAT and SPAM when used to assess petrochemical plant operator SA in a medium fidelity simulator. Hydrocracking plant operators participated in a simulation of a loss of hydrogen to their simulated plant, where SA was assessed in addition to a set of performance variables, and workload. Results of this investigation showed SAGAT Accuracies to be predictive of certain performance variables. Although SPAM and SAGAT were not sensitive to differences in task workload, neither measure was significantly intrusive on primary task performance suggesting that these metrics can be used in future experiments in petrochemical refining.</p>

Three experiments are presented that investigated the effects of distracting information on the processing of stimuli for younger and older adults. The first two experiments were controlled laboratory experiments, in which the flanker paradigm was used to investigate whether older and younger adults were affected differently by response compatible or incompatible information. Typically performance measures indicate better performance in terms of reaction times if distracting information is response compatible and reduced performance if distracting information is incompatible with a response to be executed. As an additional variable, the stimulus-to-response mapping was manipulated to investigate whether younger but not older adults were able to reduce the influence of interfering information. The stimulus-to-response mapping was either consistent or varied, and it was assumed that varied but not consistent mapping allowed subjects to reduce the interfering effects of response-incompatible information. The data in the first experiment indicated no differences between younger and older adults. However, the data in the second experiment showed that younger but not older adults were able to reduce the processing of irrelevant information. A reduction of interference in the varied mapping condition could be observed only for younger but not for older adults. Subsequently, the results of these experiments were modeled by means of a connectionist network. The test of the network using linear regression indicated a good fit between the model and the empirical data, separated by each age group, indicating the appropriateness of the theoretical assumptions of the model. The third experiment investigated the effect of compatibility using realistic stimuli, i.e., traffic signals and signs, in order to determine how compatibility governs performance in a more applied setting. No specific age-related performance deficits were observed, however, both age groups benefited from compatible information. This allowed us to derive recommendations for the design of traffic signals and signs.

The study examined whether an instruction-based strategy (studying the instructions before attempting the task) or a task-based strategy (attempting the task and referencing instructions) was more effective for procedural performance and learning. Four groups of participants learned to perform macram tasks and assembly tasks, and received detailed instructions at different times in the process of attempting the tasks. Performance was assessed at training and a week later by recording task completion time, correctness, and subjective cognitive load. The strategy for using instructions affected initial performance on the macram tasks, where instruction-based strategy was superior, but not later retention or transfer. This pattern of results was not found for the assembly tasks indicating that characteristics of the tasks influenced the effectiveness of the strategy for using instructions.

As automation becomes increasing ubiquitous, it is important to know how differences in introducing automated systems will affect human-automation interactions. There are two main ways of introducing expected reliability of an automated system to users: explicitly telling operators what to expect or giving operators experience using the system. This study systematically investigated the effect of expectation format initially and over time on: 1) perceptions of reliability and system usage, and 2) human responses to automation (e.g., compliance, reliance, and overall dependence). Initially, there was an effect of expected level for explicit statement groups, whereas there was no effect of expected level for initial exposure groups. Over time, explicit statement groups had more stable perceptions of system reliability than the initial exposure groups. In general, perceived reliability did not converge to actual system reliability (75%) by the end of the study. Additionally, perceived reliability had a weak, but positive relationship with actual system use, whereas perceptions of system use (e.g., perceived dependence) had a strong, but negative relationship with actual system use. Outside of initial effects seen with perceived reliability, there were few initial differences between expectation formats. Almost all groups tended to initially comply more than rely, with the exception of the initial exposure – lower-than group. Over time, level of expectation for initial exposure groups influenced reliance. There were no differences between expectation groups on compliance and dependence over time. In general, dependence and compliance increased or stayed the same as time using the system increased. This pattern was also seen with reliance, with the exception of the initial exposure - higher-than group decreasing reliance over time. Results from this study have implications for both theory and practice. The research findings both support and augment the existing conceptual model of automation. A better understanding of the differential effects of expectation format and introduced level of expectations can lead to introductions of automated systems that are best suited to the system’s goals, ultimately improving system performance.

Cognitive aging research has demonstrated reliable declines in memory ability with age, and, in response, several memory enhancement programs have been developed to address these concerns. Most research indicates that these programs are beneficial. However, research into the predictors of memory enhancement outcomes is limited. In brief, age, cognitive status, and memory ability have been shown to be influential. Only a few studies have investigated other potentially important psychosocial influences such as personality, metacognition, and coping styles. The goal of this study was to identify potentially important demographic, cognitive, and psychosocial influences on memory enhancement intervention outcomes. Thirty-nine older adults completed a multifaceted memory enhancement program that included psycho-education, memory compensatory strategy instruction, and discussion aimed at addressing metacognitive concerns and ageist stereotypes. Eighteen participants served as delayed-treatment controls. Predictor variables included demographic, cognitive (3MS, HVLT, Buschke Cued Recall Protocol), personality characteristics (NEO-PI-R), coping styles (Brief Cope), and metacognitive measures (MCI, MIA). Dependent measures including subjective (MMQ) and objective (Face/Name Recall, Grocery List Recall, Story Detail Recognition, Strategy Application) memory measures were obtained pre- and post-intervention. The current memory enhancement program was effective in improving both subjective and objective memory functioning immediately following program completion. Results revealed individual variation in outcomes ranging from 30 to 60 percent of participants showing improvement depending on the measure assessed. Improvements in subjective memory functioning were maintained at three-month follow-up. Investigation of predictors of individual differences in outcome indicated that memory performance scores were the most consistent predictor of objective memory functioning improvement, although metacognitive factors were also influential. Immediate improvement in subjective memory functioning was associated with both metacognitive ratings and memory performance scores whereas only metacognitive ratings were associated with lasting subjective improvement. In general, metacognitive constructs of memory efficacy, controllability, and locus of control appeared to be associated with positive intervention outcomes. An unexpected finding of higher levels of memory-related anxiety being associated with positive outcomes was noted. Personality characteristics (e.g., openness, neuroticism) were predictive of immediate increases in memory strategies usage. Implications for cognitive rehabilitation and social cognitive theory and clinical application are discussed.

The relations between mismatched parent-adolescent autonomy beliefs, and psychological adjustment and parenting self-efficacy were investigated among 89 immigrant Chinese Canadian families with early adolescents. Hierarchical regression analyses assessed whether interactions between parents’ autonomy beliefs and adolescents’ autonomy beliefs predicted psychological adjustment and parenting self-efficacy. Parent-adolescent conflict intensity was evaluated as a mediator of these relations. Parental warmth was evaluated as a moderator of the relations between autonomy beliefs and adolescent psychological adjustment. When adolescents held early expectations for autonomy, mothers who held later expectations for autonomy reported lower parenting self-efficacy. When fathers perceived high decision making independence, adolescents who perceived low decision making independence reported fewer depressive symptoms. Conflict intensity did not mediate these relations. Although parental warmth did not moderate in the predicted manner, fathers' warmth moderated the relation between fathers’ expectations for autonomy and adolescent self-esteem. Implications for healthy adolescent autonomy among immigrant Chinese Canadian families are discussed.

Objective: The Six Elements Task (SET; Shallice and Burgess, 1991; Burgess et al., 1996) measures examinees’ ability to plan and organize their behaviour, form strategies for novel problem solving, and self-monitor. The task has adequate specificity (Wilson et al., 1996), but questionable sensitivity to mild impairments in executive function (Jelicic, et al., 2001). The SET is vulnerable to practice effects. There is a limited range in possible scores, and ceiling effects are observed. This dissertation sought to evaluate the validity and clinical utility of a modification of the SET by increasing the difficulty of the test, and expanding the range of possible scores in order to make it more suitable for serial assessments. Participants and Methods: The sample included 26 individuals with mixed acquired brain injury, and 26 healthy matched controls (20 – 65 years). Participants completed a battery of neuropsychological tests on two occasions eight weeks apart. To control for confounding variables in executive function test performance, measures of memory, working memory, intelligence, substance abuse, pain, mood and personality were included. Self and informant reports of executive dysfunction were also completed. The two groups’ performances on the various measures were compared, and the external validity of the 12ET was examined. In addition, normative data and information for reliable change calculations were tabulated. Results: The ABI group exhibited very mild executive function deficits on established measures. The matched control group attempted more tasks on the 12ET, but the difference was non significant. Neither group tended to break the rule of the task. The 12ET showed convergent validity with significant correlations with measures of cognitive flexibility (Trailmaking B and Ruff Figural Fluency), and a measure of planning (Tower of London). The 12ET and published measures were also significantly correlated with intelligence in the brain-injured group. The 12ET did not show divergent validity with a test of visual scanning speed (Trailmaking A). No demographic variables were found to be significant predictors of 12ET performance at Time 2 over and above performance at Time 1, and both participant groups obtained the same benefit from practice. The 12ET did not suffer from ceiling effects on the second administration, and the test-retest reliability of the 12ET variables ranged from low (r = .22 for Rule Breaks in the brain-injured group) to high (r = .78 for Number of Tasks Attempted in the control group). Conclusions: Despite their (often severe) brain injuries, this sample of brain injured participants did not demonstrate executive impairments on many published tests and their scores were not significantly different from the control group’s scores. Therefore, it was not possible to determine if the 12ET was a more sensitive measure of mild executive deficits than the SET. However, the increase in range did reduce the tendency for participants to perform at ceiling levels. The 12ET showed a number of significant correlations with other executive measures, particularly for the brain-injured group, though these correlations may have been moderated by general intelligence. Two variables of the 12ET, deviation from the optimal amount of time per task and Number of Tasks Completed, showed promise as measures of reliable change in this sample over an 8-week interval.