Model and Study of Threatening Tasks and Fatigue

Abstract : This was a follow-on project to "Designing, building, and testing behavioral moderators with the ACT-R cognitive architecture". This project (a) prepared a protocol for studying how cognition is affected by a stressor (task appraisal) and a mitigator (caffeine), including software for gathering data on working memory, processing speed, and visual signal detection, and a protocol for serial (repeated) subtraction (SS). (b) We ran 45 Ss using SS and 45 with a simple ATC-like task as the stressor. (c) We have analyzed the data on how performance and physiology are affected by stress. We found that stress influenced performance (probably through working memory changes) and new details of physiology stress. (d) We created cognitive models in ACT-R. (e) We compared the SS model's performance by hand and by using a GA running on a supercomputer. We found that ACT-R is a model of individuals, not groups, multiple parameter sets provided excellent fits even to individuals, and GAs are an excellent way to choose architectural parameters. (f) Opportunistically, we finished a learning model, a book on learning, and a keystroke logger for studies.