Testing of a new instrument for language analysis.


During  D-MARS 01 mission, members are working in cooperation with the Italian organization MARS PLANET  to a new experiment called PSI (Performance and Stress in Isolation) whose scope is to quantify the correlation between language and stress level.

The experiment is lead by the Mars Planet members Irene Lia Schlacht, Alessandro Alcibiade, Francesco Finazzi and for the D-MARS team by Dr. Reut Sorek-Abramovich and Nadav Khusnir. 


The PSI study elaborate as a first objective the pattern correlation between stress condition and written text which will enhance early detection and management of the stress level in the people exposed to stressful context on Earth and in Space.

The result could be applied to the early detection and countermeasure of stress increasing safety and performance in extremely dangerous context such as isolation in future deep space missions.



A large variety of studies in the scientific literature, which have their roots in the 60’s, suggest a correlation between changes in the words spectrum used in every day vocabulary, and the stress levels in the test subjects.

Stress level is a key metric that can affect the performance and the safety of humans working in complex and dangerous environments. Considering the need of early detection of stress in those contexts, people are subjected to long investigations, questionnaire, and intrusive tests like blood analysis.

The PSI aims to extrinsically and unobtrusively detect the stress level via means of analysis of the subject’s written communications.


Primary objective of the PSI Study:

Determine the correlation between stress level and several key characteristics of the test subject’s written work. This is aimed to reliably quantify and predict the current stress levels and their trends. In order to validate those empirical models, two selected psychological and physiological stress-related parameters such as short questionnaires and cardiovascular parameters, will be used as the reference baseline.


Secondary Objective of the PSI Study:

Produce a simple, sound and user-friendly tool that can be used extrinsically to assess the test subjects stress levels and trends.


·        The experiment will be performed on subjects exposed to stressful context              (i.e. isolation during space mission simulations).

·        Several sessions during the isolation period are envisioned.

·        Each session consists of three tasks to be performed with the PSI software.

·        Each session is limited to a 30 min maximum duration.



The PSI experiment results will be used to create an algorithm capable of predicting stress levels based on the written communications. The study will improve the safety of future mission enhancing the possibility of early detection of stress in crew members and allow it to be monitored and managed a timely fashion. PSI will improve the safety for missions in extreme environments both on Earth and in Space.