Table of Contents

From Dave's Pen

Article From Crucible

(a magazine of the Science Teachers Association of Ontario)

Dr. Dave Williams - Canadian Astronaut and Honourary STAO President

It gives me great pleasure to write to you as the new Honourary President of the Science Teachers Association of Ontario. Capturing the interest and imagination of our youth by providing them with exciting educational opportunities in science and technology is a critical goal that will ensure the success of Canadian scientific endeavors as we enter the next century. It is not inconceivable that somewhere in Canada, there is a secondary school student who will grow up to represent Canada on the first International Human Mission to Mars. It is our challenge to give these students the skills that they will need to reach these incredible heights!

I consider myself very fortunate to have been chosen to represent Canada as one of the Mission Specialists at Johnson Space Center. Next April, I will be flying aboard the Space Shuttle Columbia, with six of my colleagues, on a sixteen-day life science mission. The mission is being called Neurolab, and is one of a series of NASA research missions dedicated to the study of life sciences.

The pursuit of answers to questions about how the body functions in space is like a search for pieces to a grand puzzle. Many pieces are easily identified and slip readily into place. Others remain elusive. Occasionally, the placement of a single, long-sought piece brings together whole segments, creating surprise with a first look at the beginnings of the big picture. Just as the body of knowledge about space life sciences expands, so does the puzzle. The result is an ongoing invitation to continue the search. With the addition of each new piece of the puzzle, the requirements for our future residence aboard the International Space Station are clarified and our understanding of life on Earth is enriched.

Our mission is a very exciting quest, seeking to explore the two remaining frontiers of this century, outer space and inner space-the function of the human nervous system. The neurosciences focus on the function of the central and peripheral nervous system, the most complex and least understood part of the human body. Made up of the brain, spinal cord, peripheral nerves and sensory organs, this system faces major challenges during a space flight. It is involved in the regulation of blood pressure, coordinates movements and regulates sleep; areas that are all affected on a Space Shuttle mission.

Neurolab began when the U.S. Congress declared the 1990s the Decade of the Brain. NASA proposed the Neurolab mission to support this mandate. In 1991, NASA held a series of seven meetings to identify critical questions in the areas of neuroscience affected by gravity. With those areas identified, meetings were initiated with international space agencies, the National Institutes of Health, the National Science Foundation, and the Department of Defense to establish criteria for selecting proposals. The resulting announcement of opportunity drew 172 proposals from scientists around the world. After peer review by the National Institutes of Health and NASA, 33 proposals were selected, two of which were from Canadian scientists. Twenty-six of the studies will fly on the mission, including both of the Canadian experiments; and the other six will fly on others.

During the mission, our payload crew will conduct the experiments in the Spacelab module. This module was built by the European Space Agency (ESA) to sit in the payload bay of the shuttle and is connected to the mid-deck by a long tunnel. Spacelab provides a laboratory with living conditions similar to those on Earth, but with one key difference: microgravity. As the orbiter moves around the planet at a speed of 28,100 kilometers per hour (17,500 miles per hour), it and its contents are in a state of free fall which results in near weightlessness.

On the flight, the Neurolab crew will serve as both subjects and operators to complete the experiments. The crew will carry out the experiments using a wide array of biomedical instrumentation, including some instruments and devices developed especially for the mission. The crew will not be the only living things on board the shuttle. Neurolab will also carry rats, mice, two types of fish, snails and crickets.

Science Overview

Since Neurolab focuses on basic research questions in neuroscience, the mission will provide a unique contribution to the study and treatment of neurological diseases and disorders. While the foremost goal of Neurolab is to expand our understanding of how the nervous system develops and functions in space, the research will also increase our knowledge of how this system develops and functions on Earth, making the information of use to the medical community.

With all of the data collected over the years on how astronauts adapt to microgravity, researchers are beginning to understand the basics of space physiology. Each piece added to the space life sciences puzzle, however, presents more questions to be answered. For example, although all of our basic movements (walking, catching, etc.) were learned in the presence of gravity, it is curious that we can learn to function so quickly in the absence of gravity. How do the gravity-sensitive parts of the body like the inner ear, cardiovascular system and muscles learn to cope without gravity? Why are sleep and biological rhythms changed in space? Must gravity be present at the point in life when basic skills such as walking are usually learned?

These questions will be answered on our mission by taking measurements from the crew and research animals before, during and after the flight. The Neurolab experiments have been grouped into teams with eight different sections, one for each of the teams. Four teams (with a combined total of 11 experiments) will use crew members as subjects, and four teams (with 15 experiments) will study research animals. The teams studying human subjects are the Autonomic Nervous System, Sensory Motor and Performance, Vestibular and Sleep teams. The animal experimentation teams include Neuronal Plasticity, Mammalian Development, Aquatic and Neurobiology.

Neurolab has a significant place in NASA's long-range plans. Long duration space flights will become common as the International Space Station is built and occupied. This makes necessary an understanding of how the human body functions in microgravity. Neurolab is expected to contribute key answers clarifying the requirements for our future residency on the International Space Station and for aiding research on Earth.

Our mission also provides some of the greatest educational outreach opportunities of any of the previous shuttle flights. It is my hope to bring to you, in future editions of the Crucible, descriptions of a number of experiments that represent the science of Neurolab and are amenable for use with secondary school students. You can look forward to finding out what astronauts have in common with giraffes and what we can learn from tree snakes about the design of space suits. Stay tuned for further mission information in the near future! Dave Williams, Spring 1998

Astronaut Lung Function Experiment

This experiment is part of the sleep team and is designed to evaluate how respiration changes in space. In particular, the experiment is designed to evaluate the neuronal control of ventilation in response to high levels of carbon dioxide, as well as low levels of oxygen.

Normally, both of these stimuli will cause an increase in respiratory rate. It is interesting that patients with chronic bronchitis, who have high levels of carbon dioxide in their blood because their lungs no longer exchange gas as efficiently as normal, are stimulated to breathe by low levels of oxygen (not by CO2 as you and I are). If you give them oxygen to breathe, it can actually decrease their respiratory rate! (medical trivia not related to space flight). Dave is particularly proud of his Respiratory Impedance Plethysmography (RIP) suit-the black suit that he is wearing in the photo. This allows the investigators to determine the movement of his chest and abdomen while breathing. There are a number of other sensors that Dave has to wear on his left hand to record the blood oxygen and pressure levels.

There is also a shot of Dave working in the general purpose work station, essentially a glove box to allow the astronauts to perform the animal experiments in a contained environment. The kinelite, or catching, experiment is designed to look at how catching (representative of a stored complex motor response) changes in microgravity.

The electrodes on Dave's right arm allow recording of the muscle activity before and during the activity. Dave is also wearing a number of reflectors on his right arm, leg and head so that the position of his body can be analyzed as well.