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Using Real-Time Lexical Indicators to Detect Performance Decrements in Spaceflight Teams: A Methodology to Dynamically Monitor Cognitive, Emotional, and Social Mechanisms that Influence Performance (NCC958NBPF0340)
Principal Investigator
Research Area:
Behavior and performance
Species Studied
Scientific Name: Homo sapiens Species: Human

Future exploratory long-duration missions will incorporate a crew of six on a mission length of approximately 2.5 years. Challenges include the requirement for the crew to function autonomously, under significant communication delays, and with the potential for increased crew and interpersonal friction or tension. Because the health and well-being of crewmembers directly affects mission success, it is important to track cognitive and emotional changes that may indicate a deficit. One problem with many existing assessment methods is that most require direct observation of behavior or performance or self-assessment by a pen and paper-type instrument. The requirement to assess individual and team functioning at a distance suggests the potential efficacy of a methodology to assess cognitive and emotional state in real-time from ongoing or spontaneous verbal output. The basic premise of this work is that spontaneous verbal output provides a natural and valid indicator of basic cognitive processes. Natural word use is not prone to the typical limitations of self-report measurements. That is, natural language use is less subject to social desirability bias, and can be derived in real-time without interfering with the cognitive processes being measured, and without interrupting crew performance. Moreover, natural word use is reliable and consistent across time and context, and can be meaningfully measured in individuals and teams.

STRESSnet is a lexical analysis tool designed to provide a non-obtrusive means of detecting stress and related deficits in long-duration space flight through the assessment of spontaneous verbal output in real-time crew communications. The research builds on existing work on text and sentiment analysis; however, STRESSnet is unique in that (1) it is specifically designed to assess stress and related cognitive/emotional states, (2) it draws on existing astronaut communications and mission logs to develop a lexicon that includes terms unique to this environment, and (3) development of STRESSnet with the specific goal of application as a tool to assess user state and provide automatic schedule recommendations for crew work/leisure activities to counter identified deficits. STRESSnet provides an unobtrusive means to evaluate ongoing task communications within the crew and between the crew and mission control in order to assess cognitive/emotional states such as workload, negative affect, stress, anxiety, and depression. Individualization of this tool to each crewmember can be achieved in the pre-training period. This tool was tested in the Human Exploration Research Analog (HERA).

This study had the following specific aims:
1. Develop a methodology to assess cognitive and emotional state at a distance though analysis of spontaneous verbal output in real-time communications.
2. Test the feasibility of a real-time assessment tool, STRESSnet, to detect cognitive performance deficits, stress, fatigue, anxiety, and depression in the space flight operational setting.

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Dietz A, Driskell JE, Sierra MJ, Weaver SJ, Driskell T, and Salas E. “Teamwork under stress." in The Wiley Blackwell Handbook of the Psychology of Team Working and Collaborative Organization Processes. Ed. Salas E., Rico R, and Passmore J. March 17, 2017. [DOI]

Driskell JE, King J, and Driskell T. "Conducting applied experimental research." in Laboratory experiments in the social sciences, 2nd ed. Ed. Webster M and Sell J. San Diego: Elsevier, 2014. p. 451-472. [DOI]

Driskell T, Driskell JE, and Salas E. "Mitigating stress effects on team cohesion." in Team cohesion: Advances in psychological theory, methods, and practice. Ed. Salas E, Vessey WB, Estrada AX, Bingley UK., Emerald Group Publishing Limited, 2015. p. 247-270. [DOI]

Driskell T, Driskell JE, Burke CS, and Salas E. "Team roles: A review and integration." Small Group Research. 2017. Aug 1; 48(4):482-511. [DOI]

Driskell T, Salas E, and Driskell JE. "Teams in extreme environments: Alterations in team development and teamwork." Human Resource Management Review. 2018. December; 28(4):434-49. [DOI]

Marlow SL, Lacerenza CN, and Salas E. "Communication in virtual teams: A conceptual framework and research agenda." Human Resource Management Review. 2017. December; 27(4):575-89. [DOI]

Driskell JE, Salas E, and Driskell T. "Foundations of teamwork and collaboration." American Psychologist. 2018 May-June; 73(4):334-48. [DOI]

Salas E, Vessey WB, Landon LB, editors. "Team dynamics over time." Ed. E. Salas, W.B. Vessey, L.B. Landon. Bingley, UK: Emerald Publishing, 2017. 352 p. [DOI]

Salas E, Rico R, Passmore J, editors. "The Wiley-Blackwell Handbook of the Psychology of Team Working and Collaborative Processes." Ed. E. Salas, R. Rico, J. Passmore. Malden, MA: Wiley-Blackwell, 2017. 640 p. [DOI]

Salas E, Reyes DL, and Woods AL. "The assessment of team performance: Observations and needs." in "Innovative assessment of collaboration." Ed. A.A. Von Davier, M. Zhu, P.C. Kyllonen. New York: Springer Verlag, 2017. p. 21-36. [DOI]

Dinh JV, Salas E. "Factors that influence teamwork." in "The Wiley Blackwell Handbook of the Psychology of Team Working and Collaborative Processes." Ed. E. Salas, R. Rico, J. Passmore. Malden, MA: Wiley-Blackwell, 2017. p. 15-42. [DOI]

Dietz A, Driskell JE, Sierra MJ, Weaver SJ, Driskell T, Salas E. "Teamwork under stress." in "The Wiley Blackwell Handbook of the Psychology of Team Working and Collaborative Processes." Ed. E. Salas, R. Rico, J. Passmore. Malden, MA: Wiley-Blackwell, 2017. p. 297-316. [DOI]

Driskell JE, Salas E. "Sustaining individual motivation in high-demand team environments." in "Individual Motivation within Groups: Social Loafing and Motivation Gains in Work, Academic, and Sports Teams." Ed. S. Karau. San Diego: Academic Press, 2018. ISBN: 978-0128498675.

Driskell T, Driskell JE, Salas E. "Lexicon as a predictor of team dynamics." in "Team Dynamics over Time. (Research on Managing Groups and Teams, Volume 18)." Ed. E. Salas, B. Vessey, L. Landon. Bingley, UK: Emerald Group Publishing, 2017. p. 231-257.

Task performance analysis
Stress, psychological

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Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
HERA Campaign 1 02/27/2014 09/11/2014 Four 7-day missions
HERA Campaign 2 01/30/2015 08/27/2015 Four 14-day missions
HERA Campaign 3 01/26/2016 10/19/2016 Four 30-day missions
NEEMO 18 07/21/2014 07/29/2014 9 days

Human Research Program (HRP) Human Research Roadmap (HRR) Information
Crew health and performance is critical to successful human exploration beyond low Earth orbit. The Human Research Program (HRP) investigates and mitigates the highest risks to human health and performance, providing essential countermeasures and technologies for human space exploration. Risks include physiological and performance effects from hazards such as radiation, altered gravity, and hostile environments, as well as unique challenges in medical support, human factors, and behavioral health support. The HRP utilizes an Integrated Research Plan (IRP) to identify the approach and research activities planned to address these risks, which are assigned to specific Elements within the program. The Human Research Roadmap is the web-based tool for communicating the IRP content.

The Human Research Roadmap is located at:

+ Click here for information of how this experiment is contributing to the HRP's path for risk reduction.

Additional Information
Managing NASA Center
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Eric Gallagher
Institutional Support
National Space Biomedical Research Institute (NSBRI)
Alternate Experiment Name
Proposal Date
Proposal Source
2012 Crew Health NNJ12ZSA