Decreased Information Replacement of Working Memory After Sleep Deprivation: Evidence From an Event-Related Potential Study

Working memory (WM) components are altered after total sleep deprivation (TSD), both with respect to information replacement and result judgment. However, the electrophysiological mechanisms of WM alterations following sleep restriction remain largely unknown. To identify such mechanisms, event-related potentials were recorded during the n-back WM task, before and after 36 h sleep deprivation. Thirty-one young volunteers participated in this study and performed a two-back WM task with simultaneous electroencephalography (EEG) recording before and after TSD and after 8 h time in bed for recovery (TIBR). Repeated measures analysis of variance revealed that, compared to resting wakefulness, sleep deprivation induced a decrease in the P200 amplitude and induced longer reaction times. ERP-component scalp topographies results indicated that such decrease primarily occurred in the frontal cortex. The N200 and P300 amplitudes also decreased after TSD. Our results suggest that decreased information replacement of WM occurs after 36 h of TSD and that 8 h TIBR after a long period of TSD leads to partial restoration of WM functions. The present findings represent the EEG profile of WM during mental fatigue

Teaching tactics as armies integrate. A comparative case study of United States Marine Corps schools and the Norwegian Military Academy

Master of Arts in War StudiesThe tactical level is academically not well developed and there is a paucity of literature on the former. Yet it has become more important in the recent years mainly due to shrinking defence budgets and the increasing number of multinational joint operations. This incites nations to integrate more closely and armies find themselves cooperating at ever lower unit levels. Such integration necessitates a similar understanding of tactics to remain effective. Officers first formally encounter tactics during their training at military academies. This thesis examines how junior officers are educated in tactics at the Norwegian Military Academy and two comparable United States Marine Corps schools. Based on established military theory, indicators for effective tactical education are formulated and applied to the teaching in these schools. The thesis uncovers that the schools’ theoretical approach to tactical education is essentially identical, but its practical implementation differs

The power of the cognitive unconscious: the case of implicit learning

The present paper highlights the power of unconscious processes within the framework of implicit learning, a research area that has attracted extensive attention in the past decades. More specifically, it discusses theoretical issues concerning this multifaceted type of learning that occurs without conscious awareness and presents various applications in different learning settings and research domains, and in varied populations. Another main focus of this review is on recent advances in our understanding of the factors that affect implicit learning, including motives, attention, affective states, and general knowledge. The paper ends with conclusions and general principles drawn from research on a phenomenon with extended applications both in the lab and in everyday life and underlines the necessity for further research that will refine our methods of distinguishing conscious and unconscious processes and provide answers to unresolved issues and contradictory findings.

Information Behaviors and Cognitive Modes Used for Cyber Situation Assessment

The purpose of this dissertation research was to examine the information behaviors and cognitive modes used by expert cyber defenders when completing cyber situation assessment tasks (SA-tasks) of different complexities. Theoretical propositions from Library and Information Science (LIS) task-complexity research and the Cognitive Continuum Theory (CCT) informed the theoretical framework. LIS task-complexity research predicts that increased task complexity results in numerous changes in information-source and information-type use. The CCT predicts that increased task complexity results in a shift from analytical to intuitive cognition. A multiple-case studies design was selected as the research approach. The Critical Decision Method served as the basis for semi-structured, retrospective interviews conducted with 21 expert cyber defenders from small defense companies. The data analysis techniques included directed content analysis, pattern matching, and statistical analysis (the Freeman-Halton extension of Fisher's Exact test). The main findings of this study are as cyber SA-task complexity increased, the expert cyber defenders sought more technical information, used more external sources, including external experts, and based their information behaviors on intuitive cognition. These findings support several of the theoretical predictions from LIS task-complexity research and the CCT. The findings are important because they show that the expert cyber defenders base their information behaviors on years of experience in the cyber defense domain and on years of experience in designing their own companies' security postures. Each company has its own security posture as well as its own level of acceptance of risk. Therefore, cyber situation assessment tools need a design that can be tailored for each company. Additionally, methods are needed to elicit the intuitive processes used by expert cyber defenders in order to train novice cyber defenders as well as other expert cyber professionals taking over the experts' localized cyber defense roles.Ph.D., Computer Science -- Drexel University, 201