Abstract. Research spanning decades has generated a long list of phenomena associated with human spatial information processing. Additionally, a number of theories have been proposed about the representation, organization and processing of spatial information by humans. This paper presents a broad account of human spatial competence, integrated with the ACT-R cognitive architecture. Using a cognitive architecture grounds the research in a validated theory of human cognition, enhancing the plausibility of the overall account. This work posits a close link of aspects of spatial information processing to vision and motor planning, and integrates theoretical perspectives that have been proposed over the history of research in this area. In addition, the account is supported by evidence from neuropsychological investigations of human spatial ability. The mechanisms provide a means of accounting for a broad range of phenomena described in the experimental literature.

This research compares the general strategy described by participants doing an orientation task to two strategies described in past research on a different kind of spatial task, perspective-taking (array rotation and viewer rotation). This evaluation indicated that participants were quite flexible and efficient in their approach to the task. The strategy described in participants ’ verbal reports made use of both of the perspective-taking strategies within individual trials. In addition, each alternative was applied in situations where previous research indicates that it holds an advantage over the other alternative. This research extends research on strategy use in spatial tasks by (1) showing how similar strategies can be applied to different kinds of spatial tasks and (2) illustrating how alternative strategies can be intermixed within a single task to produce efficient overall performance.

Humans use their spatial information processing abilities flexibly to facilitate problem solving and decision making in a variety of tasks. This article explores the question of whether a general strategy can be adapted for performing two different spatial orientation tasks by testing the predictions of a computational cognitive model. Human performance was measured on an orientation task requiring participants to identify the location of a target either on a map (find-on-map) or within an egocentric view of a space (find-in-scene). A general strategy instantiated in a computational cognitive model of the find-on-map task, based on the results from Gunzelmann and Anderson (2006), was adapted to perform both tasks and used to generate performance predictions for a new study. The qualitative fit of the model to the human data supports the view that participants were able to tailor a general strategy to the requirements of particular spatial tasks. The quantitative differences between the predictions of the model and the performance of human participants in the new experiment expose individual differences in sample populations. The model provides a means of accounting for those differences and a framework for understanding how human spatial abilities are applied to naturalistic spatial tasks that involve reasoning with maps.

The ability to process spatial information is crucial for various tasks as diverse as, navigation, planning layouts, and managing abstract concepts. Accordingly, considerable effort has been spent on understanding how spatial cognition is realized in the human mind. These endeavors have, however, so far virtually neglected one important aspect of spatial cognition, namely control. In this contribution we show that neglecting control constitutes a serious lack in understanding spatial cognition. Moreover, we propose conceptions for computational cognitive models including control for two particular spatial cognition tasks. Besides constituting first approaches to integrating control and spatial cognition these models potentially allow giving a more detailed account of the respective spatial cognition phenomena than currently available theories.

examine the duration of restart period that would be needed to recycle to the work force with optimal performance. Based on the results of this study, a second, Phase II, study was conducted between February 26 and October 31, 2010, to examine an additional experimental condition. This technical report presents the design, methods, research findings, and conclusions of the Phase II study. The most important finding was that a restart period containing two biological nights (58 hours in duration as implemented in this study), relative to a restart period with only one biological night (34 hours per the present hours of service regulations), may improve the effectiveness of the restart period for nighttime driving operations, yielding a greater potential for recovery from fatigue before recycling to the work force. This technical report may be of interest to anyone interested in fatigue and its management in commercial motor vehicle operations and other modes of transportation. This is the final report of the study. NOTICE This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The United States Government assumes no liability for

Circadian rhythms cause alertness declines at night, producing performance decrements across cognitive domains and tasks. Building on the learning mechanisms for declarative knowledge instantiated in the ACT-R cognitive architecture, this research seeks to explain the effects of circadian rhythms on performance of an orientation task performed repeatedly across two weeks by participants working either day or night shifts. The differences in performance between the two groups are best explained by varying the decay rate in declarative knowledge as a function of the time of day the task was performed. The model accounts well for task learning reflected in decreases in response times across days, as well as differences in learning between the day and night shift conditions.

Previous research has identified a variety of strategies used by novice and experienced navigators in making cardinal direction judgments (Gugerty, Brooks, & Treadaway, 2004). We developed an ACT-R cognitive model of some of these strategies that instantiated a number of concepts from research in spatial cognition, including a visual-short-term-memory buffer overlaid on a perceptual buffer, an egocentric reference frame in visual-short-term-memory, storage of categorical spatial information in visual-short-term-memory, and rotation of a mental compass in visual-short-termmemory. Response times predicted by the model fit well with the data of two groups, college students (N D 20) trained and practiced in the modeled strategies, and jet pilots (N D 4) with no strategy training. Thus, the cognitive model seems to provide an accurate description of important strategies for cardinal direction judgments. Additionally, it demonstrates how theoretical constructs in spatial cognition can be applied to a complex, realistic navigation task.

A laboratory study was conducted to examine the duration of the restart period for commercial motor vehicle drivers that would be needed to recycle to the work force with optimal performance. This report presents the design, methods, research findings, and conclusions of the study. This report may be of interest to anyone interested in fatigue and its management in commercial motor vehicle operations and other modes of transportation. This is the final report of the study. NOTICE This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or the use thereof. The contents of this Report reflect the views of the contractor, who is responsible for the accuracy of the data presented herein. The contents do not necessarily reflect the official policy of the U.S. Department of Transportation. This Report does not constitute a standard, specification, or regulation. The United States Government does not endorse products or manufacturers named herein. Trade

In this paper, we address the issue of how to identify appropriate mechanisms for cognitive control in a system that incorporates complex, spatial information processing to represent human-level competence. Our solution to this difficult issue is to use a cognitive architecture, which contains well-validated mechanisms for many aspects of human cognition, including cognitive control. This approach allows us to focus on developing theoretically motivated mechanisms for spatial competence that can be integrated into the existing architecture. The result is a more detailed and comprehensive theory, which includes a specification of how other cognitive capacities interact with spatial information processing mechanisms to generate human performance.

Gugerty, L. & Rodes, W. (in press). A cognitive model of strategies for cardinal direction judgments. Spatial Cognition and Computation. [This article has been accepted for publication & is copyrighted by Lawrence Erlbaum Associates (LEA); contact LEA for permission to use or reprint the article] A cognitive model of strategies for cardinal direction judgments