Introduction

The aim of this study is to evaluate some cognitive functions after a cycle (period) of two weeks, under confinement conditions, in a Mars analog environment.

The optimization of mental performance and faults minimization may save lives and reduce costs of space missions. Due to isolation, even in groups, and chronic exposure in a hazardous environment, astronauts may have difficulty keeping the same performance needed for mission success. Much research has been conducted to improve knowledge among physiological and psychological factors that may change human mental performance during space activities.

Cognitive performance is a very important factor for mission success. It is related to obtaining, organizing and using information from the sensori related to the environment, past experiences and mental activities. As examples of cognitive activities we may include: memory, thought, and language. With the computerized mental performance test AGARD - "The Manikin Test"— this research project is intended to measure the main aspects of mental performance: attention, spatial rotation and reaction time. It will take place during a confinement environment simulation, in a Mars Society reasearch station in the Utah desert, U.S.A,, known as the Mars Desert Research Station (MDRS).

In Aerospace Medicine, it is an important task to simulate human physiological and psychological responses in a confinement environment. Several methods to simulate confinment cycles in space, in the International Space Station (ISS) or in future lunar or Martian stations have been tested in past decades by space agencies all over the world. To date, there has been no standard method for this field of investigation.

A better knowledge as how some mental activities are performed on subacute or prolonged exposure to an isolation environment during the crew interaction and its simulation will certainly contribute to improving the safety of space missions.

Objectives

1. Evaluate mental performance (reaction time, spatial orientation, attention) by use of a computerized test at the end of 15 days of confinement in a simulation of a habitat of a Mars planet surface station.
2. Contribute to a better understanding of mental activities during subacute or prolonged isolation exposition, as in orbital flights, ISS periods, future lunars or Martian stations cycles, with the safety improvement as scope
3. Evaluate the need for unique psychological training designs for certain cognitive functions of space mission crews (astronauts).
4. Improve specific abilities to conduct mental performance tests during Mars analog environment simulations at other sites, such as the Flasline Mars Arctic Research Station in the Canadian Arctic.

Methods
Equipment to be used:

• Computer
• Computerized Mental Performance Test -"The Manikin Test"

The test to measure the voluntary mental performance is a computerized psychological test of "AGARD - Devised Standardised Tests for Environmental Stressor Battery", which was already used on several studies to evaluate mental performance at altitude.

The "Manikin Test" measures spatial orientation, attention, time of reaction in milliseconds, and it takes about four minutes to be completed. A computer, a display device and a keyboard will be used.

The software consists of a human puppet image which can be moved back and forth, up or down, in any combination. Positive and negative signs randomly appear in one of the puppet hands and below him. The test consists of identifying in which of the puppet´s hands, right or left, is the same sign as shown below the puppet.

Protocol

The experiment comprises three different phases:

1. Selection Phase
2. Training Phase
3. Testing Phase
   3.1. Onset of Confinement Cycle
   3.2. Final of Confinemnt Cycle

1. Selection Phase
   All personnel of MDRS Crew 35, "Pisces Team", will be invited to take part as subjects of this research project.
   
   This crew will be composed by healthy volunteers, all male, with no race restriction, aged between 18 and 50 years old. After reading the explanation project brochure, its risks and benefits, and having clarified any of their doubts, the selected crew volunteers will submit to anamnesis (?) and a physical examination. Anyone may give up volunteering at any time, with no prejudice.
   
   Exclusion Medical Criteria:
   • Use of any medication under test within last 30 days
   • Blood donation or significant blood loss within 30 days of the study
   • Significant gastrointesntinal condition, asthma or epilepsy
   • Etilism or drugs abuse
   • Psychiatric disorders
   
   
2. Training Phase
   The training sessions are supposed to last about one hour and will be undertaken until the volunteers have learned the computerized psychological test.
   
   The learning criteria include:
   1. Time of reaction of 1.2 seconds or less
   2. Correct answer percentage of 90% or higher
   The time gap between training sessions and the first test shall not exceed two days and shall not occur on the last training day.
   
   
3. Testing Phase
   Before test phase onset, the volunteer is required to answer a questionnaire, based on the KSS sleeping scale. It will be a double-blind study.
   
   3.1. Confinement Cycle Onset
   The computerized test shall be taken after training sessions, which shall not exceed two days and not in the same day of last training session.
   
   3.2. Final of Confinement Cycle
   The computerized test shall be taken on the day before the last day of confinement, about 10 days after of first test, which was taken at the beginning of the confinement period.

Statistic Analytics

1. Training phase
   The results of tests taken during the training phase will be the mean and the standard deviation of volunteers’ reaction times and percentage of right or wrong answers by test.
2. Testing phase
   The results of tests conducted under the testing phase will be analyzed by t-test, in which the means of the tests will be compared, and also with tests taked out of the confinement cycle (control). The significance level will be p < 0.05. Data will be analyzed using Excel.

Study Risks

There are no risks.

Benefits

1. Evaluate alterations on mental performance, including reaction time and spatial rotation, needful for accomplishment of any space mission, on the variation of confinement cycle simulating Mars surface habitat.
2. Contribute to space science by increasing the understanding of mental performance on orbital flights, ISS lengths of time, interplanetary journeys and future lunar or Martian habitats.
3. To design new psychological training programs to improve astronauts mental performance in collective isolation conditions and change of environment as in length of time on ISS or on a voyage to Mars.

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