Sleep deprivation and sustained attention performance: integrating mathematical and cognitive modeling

A long history of research has revealed many neurophysiological changes and concomitant behavioral impacts of sleep deprivation, sleep restriction, and circadian rhythms. Little research, however, has been conducted in the area of computational cognitive modeling to understand the information processing mechanisms through which neurobehavioral factors operate to produce degradations in human performance. Our approach to understanding this relationship is to link predictions of overall cognitive functioning, or alertness, from existing biomathematical models to information processing parameters in a cognitive architecture, leveraging the strengths from each to develop a more comprehensive explanation. The integration of these methodologies is used to account for changes in human performance on a sustained attention task across 88 h of total sleep deprivation. The integrated model captures changes due to time awake and circadian rhythms, and it also provides an account for underlying changes in the cognitive processes that give rise to those effects. The results show the potential for developing mechanistic accounts of how fatigue impacts cognition, and they illustrate the increased explanatory power that is possible by combining theoretical insights from multiple methodologies.     

The Palestinian/Israeli Conflict: A Geopolitical Identity Disorder

In this paper, the author considers that the large-group dynamics in certain war-torn, hot spots throughout the world are symptoms of a “geopolitical identity disorder.” He extrapolates from the model of the severely traumatized psyche in dissociative identity disorder in which there is so much intolerable emotion, destructive aggression and conflict that different selves with different identities develop which are unable to recognize how interdependent and related they actually are. In the most extreme cases, one dissociated self tries to kill off “the other” in order to gain exclusive control of the body and make it comply with his or her wishes and vision. In actuality, however, such an attempt is a dissociated suicide plan with lethal implications. This model is applied to the Palestinian/Israeli situation where there is a deadly battle over the land. A clinical vignette is offered to illustrate these ideas and offer possibilities for help.     

Learning from Tolstoy: Forgetfulness and Recognition in Literary Edification

Philosophers have often applied a distinctively epistemic framework to the question of how moral knowledge can be derived from fictional literature, by considering how true propositions, or their argumentative support, can be the cognitive fruits of reading works of fiction. I offer an alternative approach. I focus not on whether readers fail to assent to the truth of a proposition or fail to provide it rational support. Instead, I focus on how readers fail to accord a truth (which they already accept) adequate importance in their web of beliefs about living a good human life. This is a form of ignorance, but in the form of neglect, or failure to pay proper regard – which is one sense of the term ‘forgetfulness’. I argue that works of fictional literature may, at times, stimulate audience members to overcome their own particular forms of forgetfulness in this respect. And I use Tolstoy’s The Death of Ivan Ilyich as a case in point.

Crisis Management: Looking Back to Look Forward

Alexander George made a seminal contribution to theories of preventive diplomacy, crisis management, deterrence, and coercive diplomacy. Although he made his contribution in the highly structured environment of the Cold War, his analysis of the close connections between positive and negative inducements, the importance of interests in shaping outcomes, and the dangers of threat-based strategies as substitutes for policy speaks to the central challenges of contemporary global politics.     

Experimental pragmatics: a Gricean turn in the study of language

Discerning the meaning of an utterance requires not only mastering grammar and knowing the meanings of words but also understanding the communicative (i.e., pragmatic) features of language. Although it has been an ever present aspect of linguistic analyses and discussions, it is only over the last ten years or so that cognitive scientists have been investigating--in a concerted fashion--the pragmatic features of language experimentally. We begin by highlighting Paul Grice's contributions to ordinary language philosophy and show how it has led to this active area of experimental investigation. We then focus on two exemplary phenomena--'scalar inference' and 'reference resolution'--before considering other topics that fit into the paradigm known as 'experimental pragmatics'.     

Defining the boundary of childhood amnesia

When adults are asked to recall their earliest autobiographical memories most can recall nothing about their infancy and early childhood, a phenomenon commonly referred to as childhood amnesia. There is general consensus regarding the existence of childhood amnesia, but there remains considerable debate over its boundary. Most researchers have argued that the boundary of childhood amnesia occurs between the ages of 3 and 4 years, but in 1993 Usher and Neisser published a highly influential paper, which has subsequently been used to argue that the boundary may be as low as 2 years. In the present experiment we examined how changes in scoring criteria influence our estimates of the age of adults' earliest memories. We conclude that some coding criteria are more valid than others and that the best estimates of childhood amnesia will include measures of free recall in addition to the specific questions that have dominated prior research in this area.     

Rorschach Comprehensive System data for a sample of 52 older adult nonpatients from the United States

This study is composed of 52 older adults, ages 60 to 80, all from the United States. In addition to being administered the Rorschach (Rorschach, 1942), all participants also were administered the Wechsler Adult Intelligence Scale-Revised (WAIS-R; Weschler, 1981), the Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989), the Neuro Cognitive Status Examination (NCSE; Kiernan, Mueller, Langston, & Van Dyke, 1987), and the Trail Making Test Part B (Reitan, 1958; Reitan & Wolfson, 1993). Examiners included the principal author as well as three other trained examiners. Inclusion criteria are described. Interrater reliability statistics at the response level are presented along with scores for the Rorschach Comprehensive System (CS; Exner, 1995).