An important application of cognitive architectures is to provide human performance models that capture psychological mechanisms in a form that can be “programmed” to predict task performance of human–machine system designs. Although many aspects of human performance have been successfully modeled in this approach, accounting for multitalker speech task performance is a novel problem. This article presents a model for performance in a two-talker task that incorporates concepts from psychoacoustics, in particular, masking effects and stream formation.

The field of cognitive modeling has progressed beyond modeling cognition in the context of simple laboratory tasks and begun to attack the problem of modeling it in more complex, realistic environments, such as those studied by researchers in the field of human factors. The problems that the cognitive modeling community is tackling focus on modeling certain problems of communication and control that arise when integrating with the external environment factors such as implicit and explicit knowledge, emotion, cognition, and the cognitive (...) system. These problems must be solved in order to produce integrated cognitive models of moderately complex tasks. Architectures of cognition in these tasks focus on the control of a central system, which includes control of the central processor itself, initiation of functional processes, such as visual search and memory retrieval, and harvesting the results of these functional processes. Because the control of the central system is conceptually different from the internal control required by individual functional processes, a complete architecture of cognition must incorporate two types of theories of control: Type 1 theories of the structure, functionality, and operation of the controller, and type 2 theories of the internal control of functional processes, including how and what they communicate to the controller. This book presents the current state of the art for both types of theories, as well as contrasts among current approaches to human-performance models. It will be an important resource for professional and student researchers in cognitive science, cognitive-engineering, and human-factors.Contributors: Kevin A. Gluck, Jerry T. Ball, Michael A. Krusmark, Richard W. Pew, Chris R. Sims, Vladislav D. Veksler, John R. Anderson, Ron Sun, Nicholas L. Cassimatis, Randy J. Brou, Andrew D. Egerton, Stephanie M. Doane, Christopher W. Myers, Hansjorg Neth, Jeremy M Wolfe, Marc Pomplun, Ronald A. Rensink, Hansjorg Neth, Chris R. Sims, Peter M. Todd, Lael J. Schooler, Wai-Tat Fu, Michael C. Mozer, Sachiko Kinoshita, Michael Shettel, Alex Kirlik, Vladislav D. Veksler, Michael J. Schoelles, Jerome R. Busemeyer, Eric Dimperio, Ryan K. Jessup, Jonathan Gratch, Stacy Marsella, Glenn Gunzelmann, Kevin A. Gluck, Scott Price, Hans P. A. Van Dongen, David F. Dinges, Frank E. Ritter, Andrew L. Reifers, Laura Cousino Klein, Michael J. Schoelles, Eva Hudlicka, Hansjorg Neth, Christopher W. Myers, Dana Ballard, Nathan Sprague, Laurence T. Maloney, Julia Trommershauser, Michael S. Landy, A. Hornof, Michael J. Schoelles, David Kieras, Dario D. Salvucci, Niels Taatgen, Erik M. Altmann, Richard A. Carlson, Andrew Howes, Richard L. Lewis, Alonso Vera, Richard P. Cooper, and Michael D. Byrne. (shrink)

Visual Search without Selective Attention calls into question the necessity of a covert selective attention mechanism by implementing a formal model that includes basic visual mechanisms, saccades, and simple task strategies. Across three search tasks, the model accounts for response times as well as the proportion of errors observed in human participants, including effects of item crowding in the visual stimulus.

Neural substrates of fatigue in traumatic brain injury are not well understood despite the considerable burden of fatigue on return to productivity. Fatigue is associated with diminishing performance under conditions of high cognitive demand, sense of effort, or need for motivation, all of which are associated with cognitive control brain network integrity. We hypothesize that the pathophysiology of TBI results in damage to diffuse cognitive control networks, disrupting coordination of moment-to-moment monitoring, prediction, and regulation of behavior. We investigate the cingulo-opercular (...) and frontoparietal networks, which are engaged to sustain attention for task and maintain performance. A total of 61 individuals with mild TBI and 42 orthopedic control subjects participated in functional MRI during performance of a constant effort task requiring altering the amount of effort utilized to manually squeeze a pneumostatic bulb across six 30-s trials. Network-based statistics assessed within-network organization and fluctuation with task manipulations by group. Results demonstrate small group differences in network organization, but considerable group differences in the evolution of task-related modulation of connectivity. The mild TBI group demonstrated elevated CO connectivity throughout the task with little variation in effort level or time on task, while CO connectivity diminished over time in controls. Several interregional CO connections were predictive of fatigue in the TBI group. In contrast, FP connectivity fluctuated with task manipulations and predicted fatigue in the controls, but connectivity fluctuations were delayed in the mild traumatic brain injury group and did not relate to fatigue. Thus, the mTBI group’s hyper-connectivity of the CO irrespective of task demands, along with hypo-connectivity and delayed peak connectivity of the FP, may allow for attainment of task goals, but also contributes to fatigue. Findings are discussed in relation to performance monitoring of prediction error that relies on internal cues from sensorimotor feedback during task performance. Delay or inability to detect and respond to prediction errors in TBI, particularly evident in bilateral insula-temporal CO connectivity, corresponds to day-to-day fatigue and fatigue during task performance. (shrink)

Our sense of self includes awareness of our thoughts and movements, and our control over them. This feeling can be altered or lost in neuropsychiatric disorders as well as in phenomena such as “automatic writing” whereby writing is attributed to an external source. Here, we employed suggestion in highly hypnotically suggestible participants to model various experiences of automatic writing during a sentence completion task. Results showed that the induction of hypnosis, without additional suggestion, was associated with a small but significant (...) reduction of control, ownership, and awareness for writing. Targeted suggestions produced a double dissociation between thought and movement components of writing, for both feelings of control and ownership, and additionally, reduced awareness of writing. Overall, suggestion produced selective alterations in the control, ownership, and awareness of thought and motor components of writing, thus enabling key aspects of automatic writing, observed across different clinical and cultural settings, to be modelled. (shrink)

D E Cooper; Is Language Learned?1, Journal of Philosophy of Education, Volume 9, Issue 1, 30 May 2006, Pages 93–104, https://doi.org/10.1111/j.1467-9752.1975.tb.

Infinite time Turing machines with only one tape are in many respects fully as powerful as their multi-tape cousins. In particular, the two models of machine give rise to the same class of decidable sets, the same degree structure and, at least for partial functions f : ℝ → ℕ, the same class of computable functions. Nevertheless, there are infinite time computable functions f : ℝ → ℝ that are not one-tape computable, and so the two models of infinitary computation (...) are not equivalent. Surprisingly, the class of one-tape computable functions is not closed under composition; but closing it under composition yields the full class of all infinite time computable functions. Finally, every ordinal that is clockable by an infinite time Turing machine is clockable by a one-tape machine, except certain isolated ordinals that end gaps in the clockable ordinals. (shrink)

Is God's foreknowledge compatible with human freedom? One of the most attractive attempts to reconcile the two is the Ockhamistic view, which subscribes not only to human freedom and divine omniscience, but retains our most fundamental intuitions concerning God and time: that the past is immutable, that God exists and acts in time, and that there is no backward causation. In order to achieve all that, Ockhamists distinguish ‘hard facts’ about the past which cannot possibly be altered from ‘soft facts’ (...) about the past which are alterable, and argue that God's prior beliefs about human actions are soft facts about the past. (shrink)

Causal theories of content, a popular family of approaches to defining the content of mental states, commonly run afoul of two related and serious problems that prevent them from providing an adequate theory of mental content—the misrepresentation problem and the disjunction problem. In this paper, I present a causal theory of content, built on information theoretic tools, that solves these problems and provides a viable model of mental content. This is the greatest surprise reduction theory of content, which identifies the (...) content of a signal as the event the surprisal of which is most reduced by that signal. Conceptually, this amounts to the claim that the content of a signal is the event the probability of which has increased by the largest proportion, or the event that the signal makes the most less surprising to us. I develop the greatest surprise reduction theory of content in four stages. First, I introduce the general project of causal theories of content, and the challenges presented to this project by the misrepresentation and disjunction problems. Next, I review two recent and prominent causal theories of content and demonstrate the serious challenges faced by these approaches, both clarifying the need for a solution to the misrepresentation and disjunction problems and providing a conceptual background for the greatest surprise reduction theory. Then, I develop the greatest surprise reduction theory of content, demonstrate its ability to resolve the misrepresentation and disjunction problems, and explore some additional applications it may have. Finally, I conclude with a discussion of a particularly difficult challenge that remains to be addressed—the partition problem—and sketch a path to a potential solution. (shrink)

Background: Despite the expansion of ethics consultation services, questions remain about the aims of clinical ethics consultation, its methods and the expertise of those who provide such services.Objective: To describe physicians’ expectations regarding the training and skills necessary for ethics consultants to contribute effectively to the care of patients in intensive care unit .Design: Mailed survey.Participants: Physicians responsible for the care of at least 10 patients in ICU over a 6-month period at a 921-bed private teaching hospital with an established (...) ethics consultation service. 69 of 92 eligible physicians responded.Measurements: Importance of specialised knowledge and skills for ethics consultants contributing to the care of patients in ICU; need for advanced disciplinary training; expectations regarding formal-training programmes for ethics consultants.Results: Expertise in ethics was described most often as important for ethics consultants taking part in the care of patients in ICU, compared with expertise in law , religious traditions , medicine and conflict-mediation techniques . When asked about the formal training consultants should possess, however, physicians involved in the care of patients in ICU most often identified advanced medical training as important.Conclusions: Although many physicians caring for patients in ICU believe ethics consultants must possess non-medical expertise in ethics and law if they are to contribute effectively to patient care, these physicians place a very high value on medical training as well, suggesting a “medicine plus one” view of the training of an ideal ethics consultant. As ethics consultation services expand, clear expectations regarding the training of ethics consultants should be established. (shrink)

Antimicrobial resistance is a critical public health challenge, and the contribution of the widespread use of antimicrobials in food animals to bacterial drug resistance and human infection demands greater policymaker attention. Global consumption of antimicrobials in food animal production by 2030 is projected to rise by two-thirds due to increases in both food animal production and demand for animal products. In the United States, the volume of antibiotics sold for use in food-producing animals is at least three times greater than (...) that sold for human use. A One Health approach that emphasizes the connections among the health of humans, animals, and the environment is needed to address antibiotic resistance in an integrated manner. This approach holds the promise of collaboration across multiple disciplines, including doctors, veterinarians, food safety professionals, and environmental health experts. (shrink)

First published in 2002. Routledge is an imprint of Taylor & Francis, an informa company.

D E Cooper; Is Language Learned?1, Journal of Philosophy of Education, Volume 9, Issue 1, 30 May 2006, Pages 93–104, https://doi.org/10.1111/j.1467-9752.1975.tb.