This is the third year of a directed research project. This past year, we have worked on the following seven aims:

1) Complete data analysis for the blue-enriched solid-state light melatonin suppression bench-marking study.

2) Present the melatonin study results at the NASA Investigators Workshop and complete a manuscript for publication.

3) Complete the setup, calibration, and staff training on polysomnographic equipment and performance testing batteries.

4) Secure necessary amendments to the approved IRB document for the first alertness study.

5) Recruit, screen, enroll, and begin running subjects for the first study on alertness and cognitive performance.

6) Identify follow-up studies.

7) As necessary, a) design and acquire new prototype solid-state light sources or b) develop modifications of current light sources for future studies.

During the first two years of this project, we made significant progress in 1) creating two prototype 122 x 122 cm solid-state blue light (475 nm) exposure systems for the studies, 2) validating the safety of these prototypes by an independent hazard analysis that met federal (ACGIH), international (ICNIRP), and NASA guidelines for safety of human ocular exposure, and 3) completing a bench-marking melatonin suppression study using the blue light prototype with eight healthy subjects.

In terms of the first aim for the past year, we completed data analysis of the bench-marking melatonin suppression study. The goals of the study were to characterize the biological potency of the prototype light units and guide the selection of the light intensity to be tested in the first alertness study. The data confirm that narrowband, polychromatic blue solid-state light suppresses melatonin in healthy subjects in a dose-response manner. Further, the data enabled the calculation of a target intensity for the first alertness study.

For the second aim, the melatonin suppression data was presented at the NASA Investigators' Workshop (West et al., 2008) and a first draft of a manuscript on the study has been completed. Revision of the manuscript by all co-authors is continuing. The intent is to submit a final manuscript to a peer-review journal during this coming year.

The third and fourth aims are concerned with our first study on the effects of narrowband, polychromatic blue solid-state light on alertness and cognitive performance in healthy male and female subjects. Although the collaborative team completed the design of this study in the prior year, further protocol modifications were necessary, and Jefferson’s IRB has approved 4 separate protocol revisions since then. In parallel, we established the polysomnography (PSG) and behavioral testing techniques for this project, and LRP staff completed the necessary training for using these methods. Erin Evans, a Registered PSG Technician at Brigham and Women’s Hospital, joined our team as a collaborator to assist with troubleshooting our PSG setup, data analysis, and data interpretation.

Progress on our fifth aim includes subject recruitment and participation in the alertness study. To date, over 170 individuals have applied to participate and have gone through initial steps of screening for the study. From that pool, more than 10 subjects have completed medical, psychological, and ophthalmological examinations, as well as screens for stability of sleep-wake cycles and drugs of abuse. Ten subjects have now completed the three-day inpatient alertness protocol. Preliminary analysis of plasma melatonin, subjective alertness, objective alertness, and neurobehavioral data are now in process. We plan to continue screening volunteers and entering eligible subjects into the protocol in the coming year.

In terms of our sixth and seventh aims, it is important to note that the experimental panel we currently are testing is not flight-worthy. A set of six different study designs has been developed to test the relative efficacy of smaller light emitting surfaces. The LRP staff has met to review these study designs with the intent of selecting a single design to best accomplish this objective. Although the details of the study design are not finalized, preliminary work on an IRB submission has been initiated. Preliminary discussions have addressed how to modify of the 122 x 122 cm exposure panels for the new study. Work on study design, exposure panel reconfiguration, and the associated IRB will continue into the coming year.

The ultimate goal of this project is to develop a lighting countermeasure that enhances alertness and cognitive performance. This year’s progress addresses Critical Risk areas 26 and 27 in the Bioastronautics Roadmap (research questions 26f, 26h, 27b, and 27f). These areas concern countermeasures that mitigate performance problems due to sleep loss and circadian disturbances. This work ultimately impacts Critical Risk 44 concerning the “mismatch between crew physical capabilities and task demands” (question 44f).

Aside from evidence of a breakdown in physical health, the effects of circadian disruption and sleep loss have long been known to have potentially dangerous behavioral effects. Mental fatigue, diminished alertness, loss of psychomotor coordination and decreased physical performance are all commonly found in individuals with sleep loss, sleep debt, or circadian misalignment. Many people also experience the same effects after air travel across several time zones. The impact of these deficits affects many industries, including transportation, manufacturing, communications, medicine, and homeland security. It has long been a source of concern for the military, as well. In the past, the U.S. Air Force has supported our laboratory to study the acute alerting effects of light (French et al., 1990; Brainard et al., 1996). Our current work for NIH has continued this effort (Lockley et al., 2006).

Existing therapeutic lighting interventions stand to benefit from enhancing our understanding of how different wavelengths of the spectrum affect human circadian and neurobehavioral regulation. A more efficient intervention with increased potency and/or fewer side effects could result. One such disorder currently being treated with bright white light is Seasonal Affective Disorder (SAD), also known as winter depression. It is estimated that as many as 1 in 5 Americans suffer from SAD or its milder version, subsyndromal Seasonal Affective Disorder (sSAD) (Lam and Levitt, 1999). Similar bright white light interventions also are used to treat jetlag. Side effects from exposure to bright white light for these and other therapies include: hypomania, headache, vision problems, nausea, dizziness, and anxiety. Optimizing the light spectrum for specific affective and/or circadian-related disorders could deliver the same medical impact with lower levels of light intensity and, potentially, with fewer side effects. Our group has completed Phase I testing of light therapy with blue solid-state lighting for patients with SAD (Glickman et al., 2006).

For this study, we have two identical 122 x 122 cm solid-state blue light sources, installed into identical exposure stations. Each light source consists of an array of 5,776 blue LEDs (peak 475 nm). These units provide a large, uniform light-emitting surface with intensity modulation. The light sources were designed and developed collaboratively with Apollo Health, an NSBRI Industrial Partner. David Sliney, Ph.D., has completed an independent safety analysis of the blue LED light sources based on national (ACGIH) and international (ICNIRP) criteria. After reviewing Dr. Sliney’s final report, James Maida of JSC and Charles Bowen, Ph.D., of Lockheed Martin confirmed that the units meet NASA’s safety standards and were co-authors with our team on an abstract showing the safety evaluation results (West et al., 2008).

The aims of this bench-marking melatonin suppression study were to characterize the biological potency of the prototype light units and to guide the selection of the light intensity to be tested in the first alertness study. Eight healthy men and women participated in the study, completing a total of 84 nighttime melatonin suppression experiments. Data analysis has been completed and, based on the results, a target intensity for the first alertness study was calculated. The data also showed that the blue LED light evokes a dose-response melatonin suppression in healthy subjects. A first draft of a manuscript on these results has been completed. Revisions of the manuscript by all co-authors will continue into year 4 of work.

Although the collaborative team completed the design of our first study on the effect of blue solid-state light on alertness and cognitive performance in the prior year, further protocol modifications were implemented, and Jefferson’s IRB has approved 4 separate protocol revisions since then. In parallel, we established the polysomnography and behavioral testing techniques for this project and LRP staff completed the necessary training for using these methods. To date, over 170 individuals have applied to participate and have gone through initial elements of screening for the alertness study. From that pool, more than 10 subjects have completed medical, psychological, and ophthalmological examinations, as well as screens for stability of sleep-wake cycles and drugs of abuse. Ten subjects have now completed the three-day inpatient alertness protocol. Preliminary analysis of plasma melatonin, subjective alertness, objective alertness, and neurobehavioral data are now in process. We plan to continue screening volunteers and entering eligible subjects into the protocol in the coming year.

3rd DIN-Expert Panel, June 2009. , Jun-2009

Circadian Disruption and Cancer, Abstract Book, June 2009. , Jun-2009

This is the second year of a new, directed research project. This past year, we have worked on the following seven aims:

1) Have independent safety analysis completed on the new solid-state lighting prototype and involve lighting engineers from Johnson Space Center (JSC) and Lockheed Martin in reviewing and approving the safety analysis and proposing any further assessments to ensure that the prototype meets NASA’s standards and applications.

2) Acquire a second solid state blue light exposure system from Apollo Light Systems, Inc., an NSBRI industrial partner. Install and characterize the second system prior to its implementation in the melatonin bench-marking studies.

3) Complete human subject recruitment and nighttime experiments for the melatonin suppression bench-marking study with blue solid-state light. Complete assay of melatonin samples and begin data analysis for this study.

4) Complete the design of the inaugural study on the effect of blue solid-state light on alertness and cognitive performance in healthy subjects.

5) Write and secure Institutional Review Board (IRB) approval of the first alertness study design.

6) Set up and calibrate polysomnographic equipment. Train staff in use of polysomnographic equipment and performance testing batteries for assessing alertness and cognitive performance in the study volunteers.

7) Recruit and screen subjects. Begin running the first experiment on alertness and cognitive performance.

As a basis for accomplishing the first aim, David Sliney, Ph.D. of Aberdeen Proving Ground provided a draft independent safety analysis based on criteria from the American College of Government and Industrial Hygiene (ACGIH) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP) during the first year of the project. The report was finalized during the current year of work. It confirmed that the blue solid-state prototype operates "at all wavelengths and emission levels that are far below limits that are recognized as maximal safe exposure values." Once finalized, the report was distributed to James Maida at JSC and Charles Bowen, Ph.D. of Lockheed Martin for review. In turn, they confirmed that the prototype meets NASA’s standards and applications. No further work is needed on this aim.

Towards the second aim, Apollo Light Systems, Inc. fabricated and delivered a second solid state blue light exposure unit to Jefferson’s Light Research Program. This light source was installed into an exposure system and characterized for spectral output and intensity control. It has been utilized in the melatonin bench-marking studies. No further work is needed on this aim.

For the third aim, human subject recruitment has been completed for the melatonin suppression bench-marking study with blue solid-state light. A total of 84 nighttime experiments with these subjects have been completed. Assay of plasma melatonin samples have been completed and data analysis has begun for this study. Preliminary data assessment indicates that two subjects may have to repeat an exposure night due to technical difficulties. Although a majority of this aim is completed, work will continue into year 3.

The fourth and fifth aims have now been accomplished, and the design is complete for our first study on the effect of blue solid-state light on alertness and cognitive performance in healthy subjects. Jefferson’s IRB formally approved the protocol on 4/17/08. Although protocol amendments may be submitted in the coming year, we are now enabled to start subject recruitment.

We are continuing work on the sixth aim. A sleep medicine physician is consulting with us on implementing polysomnography in this project, and we have hired two part time polysomnography technicians. The first polysomnography training session for the Light Research program staff was conducted on 7/9/08. Determination and purchase of the necessary polysomnography analysis software is underway. Testing of alertness and cognitive performance is being done in a separate phase-shift study, and we are currently determining if these techniques will be suitable in this project on acute alertness.

We will begin work on the seventh aim when we approach completion of the sixth aim. Subject recruitment involves a lengthy interview process, followed by a tour of the live-in laboratory where volunteers will stay for three days. Once volunteers commit to participating, they must avoid prescription or non-prescription drugs, over-the-counter drugs, recreational/street drugs, and other foreign substances. Urine toxicology screens will check compliance for these criteria. Subjects will be required to maintain a scheduled sleep-wake and light-dark cycle prior to the study, complete a daily sleep-wake log and Epsworth Sleepiness Scale, and phone into a voice mailbox to record the bed time and wake up time each day. For at least one week prior to entry into the laboratory study, they will wear a wrist activity monitor to ensure compliance with the screening criteria for maintaining a consistent sleep-wake schedule. In addition, they will be screened medically by a physician and psychologically by a clinical psychologist. Both before and after the study, subjects will have eye screens by a neuro-ophthalmologist. Failure to comply with any of these requirements will result in exclusion from the study. Work on this aim may begin as soon as August of 2008.

Aside from evidence of a breakdown in physical health, the effects of circadian disruption and sleep loss have long been known to have potentially dangerous behavioral effects. Mental fatigue, diminished alertness, loss of psychomotor coordination and decreased physical performance are all commonly found in individuals with sleep loss, sleep debt, or circadian misalignment. The impact of these dangers affects many industries, including transportation, manufacturing, communications, and medicine. It has long been a source of concern for the military, as well. Many people also experience the same effects after air travel across several time zones. In the past, the U.S. Air Force has supported our laboratory to study the acute alerting effects of light (French et al., 1990; Brainard et al., 1996). Our current work for NIH has continued this effort (Lockley et al., 2006).

Existing therapeutic interventions using light stand to benefit from enhancing our understanding of how different wavelengths of the spectrum affect human circadian and neurobehavioral regulation. A more efficient intervention with increased potency and/or fewer side effects could result. One such disorder currently being treated with bright white light is Seasonal Affective Disorder (SAD), also known as winter depression. It is estimated that as many as 1 in 5 Americans suffer from SAD or its milder version, subsyndromal Seasonal Affective Disorder (sSAD) (Lam and Levitt, 1999). Similar bright white light interventions are also used to treat jetlag. Side effects from exposure to bright white light for these and other therapies include: hypomania, headache, vision problems, nausea, dizziness, and anxiety. Optimizing the light spectrum for specific affective and/or circadian-related disorders could deliver the same medical impact with lower levels of light intensity, and potentially fewer side effects. Our group has completed Phase I testing of light therapy with blue solid-state lighting for SAD patients (Glickman et al., 2006).

This year we developed a second blue light exposure system that greatly enhances our ability to run studies more efficiently. Our two solid-state blue light sources are identical in construction, installed into identical exposure stations, and equivalent in performance. Each light source consists of an array of 5,776 blue LEDs (peak 475 nm). These LED prototypes provide a large, uniform light emitting surface with intensity modulation. The donation of the second light source illustrates the continuing commitment of Apollo Light Systems, Inc. to work with our laboratory as an NSBRI Industrial Partner.

The safety evaluation of the prototype blue solid state light sources has been completed. David Sliney, Ph.D., provided an independent safety analysis based on national (ACGIH) and international (ICNIRP) criteria. His final report confirms that the prototype light units operate “at all wavelengths and emission levels that are far below limits that are recognized as maximal safe exposure values.” James Maida at JSC and Charles Bowen, Ph.D., of Lockheed Martin reviewed this report. They confirmed that the units meet NASA’s safety standards and were co-authors with our team on an abstract showing the safety evaluation results at NASA’s 2008 HRP Investigators Workshop.

The aims of the bench-marking melatonin suppression study were to characterize the biological potency of the prototype light units and guide the selection of the light intensity to be tested in the first alertness study. Eight healthy men and women participated in this within-subjects study, completing a total of 84 nighttime melatonin suppression experiments. Assays of plasma melatonin samples have been completed and data analysis has begun. Although further analysis is required, the preliminary data show that the blue LED light evokes a dose-response melatonin suppression in healthy subjects (p<0.001). Although a majority of this aim is completed, work on it will continue into year 3.

This year, our collaborative team completed the design of our first study on the effect of blue solid-state light on alertness and cognitive performance. Jefferson’s IRB has formally approved the protocol. In parallel, we are establishing polysomnography and behavioral testing techniques for this project. The LRP staff had their first polysomnography training session on 7/9/08. Once the polysomnography and behavioral testing techniques are operational, we plan to begin subject recruitment for the first alertness study, possibly before the start of year 3 funding.

Light and Health Research Foundation Proceedings: Symposium on Light, Performance, and Quality of Life, Abstract Book, November 2007. , Nov-2007

FASEB Summer Research Conference: Melatonin Receptors: Actions and Therapeutics Proceedings, 2008. , Aug-2008

Society for Research on Biological Rhythms, 20th Anniversary Meeting, Program and Abstracts, 2008. p. 94. , May-2008

Aviation, Space, and Environmental Medicine. 2008 Mar;79(3):266-7. , Mar-2008

Sleep and Biological Rhythms. 2007 Aug;5(s1):A22. , Aug-2007

This is a new, directed research project. To initiate the work, we proposed the following seven aims:

1) Assemble a team of investigators who will create a set of study designs to be run from 2006 to 2012.

2) Establish either collaborative, consultant or subcontract agreements for elements of the work which are best done outside of Thomas Jefferson University (TJU).

3) Write and secure Institutional Review Board (IRB) approval of the first study design.

4) Design and fabricate the initial solid-state light sources for testing. These sources will serve as the independent variables in the initial study design.

5) Have an independent safety analysis completed on the solid-state lighting prototypes.

6) Purchase and calibrate equipment for assessing alertness and cognitive performance in the study volunteers.

7) Develop a multiyear plan for the development and testing of specific lighting technologies that can be installed in the CEV and other space exploration habitats for acutely enhancing astronaut and ground crew alertness.

Towards accomplishing the first two aims, written correspondence, phone calls and direct meetings were used to establish the team of investigators. Over the first year, a total of eight meetings were held: five meetings at TJU in Philadelphia, one in League City during the NASA Human Research Program Investigators Workshop, one at the External Advisory Committee meeting in Houston, and one at Johnson Space Center (JSC). As a result of these meetings, key collaborators who have formally agreed to participate on this project. These include James Maida of JSC's Habitability and Human Factors Branch; Charles Bowen, Ph.D. of Lockheed Martin's Human Factors Design team; David Dinges, Ph.D. and Namni Goel, Ph.D. from the University of Pennsylvania; Stephen Lockley, Ph.D. of Brigham and Womens Hospital and Harvard Medical School; David Sliney, Ph.D. of the U.S. Army Laser/Optical Radiation Program at Aberdeen Proving Ground; and Mark Rollag, Ph.D. of the University of Virginia. These collaborators will work with scientists and staff of TJU's Light Research Program (LRP) towards accomplishing the goals of this project. The collaborators will work on selected aspects of this project as per their expertise.

Progress towards the third aim involves the development of two experiments. Subject recruitment for the first experiment will be initiated during this month (the end of the first funding year) and the study will be completed in the second funding year. The second experiment will be initiated and run during the second year. The first experiment is a bench-marking study to characterize the biological potency of the prototype solid-state light source that is described below. A within-subjects, acute light-induced melatonin suppression study will be done with eight healthy men and women. This study will have two important outcomes. First, it will help characterize the biological efficacy of the prototype solid-state light source relative to monochromatic and polychromatic light sources previously studied in our lab. In addition, it will guide the selection of the light intensity that will be tested in the second study, which will focus on alertness. The IRB for the first study has been approved by TJU. The protocol for the second experiment, a two-day study on the alerting effects of blue light, is still being refined. Once the experimental design is completed, a separate IRB covering that work will be written and submitted for review.

Progress towards the fourth aim involves our collaboration with Apollo Light Systems, Inc., an industrial partner of NSBRI. Apollo has donated engineering time and materials to develop a large panel of narrowband blue LEDs. This light source will be the independent variable in the first two experiments discussed above. Working closely with an engineer from Apollo, we have modified the original prototype so it can provide a broad range of light intensities with no change to spectral output. Jefferson's LRP staff has thoroughly characterized the prototype radiometry and photometry. This light unit is now completely serviceable for experimental use.

Concerning our fifth aim, David Sliney, Ph.D. of Aberdeen Proving Ground has made a series of radiometric measurements of the prototype and has provided an independent safety analysis based on criteria from the American College of Government and Industrial Hygiene (ACGIH) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). His draft report confirms that the blue solid-state prototype operates "at all wavelengths and emission levels that are far below limits that are recognized as maximal safe exposure values." Once finalized, the report will be distributed to James Maida at JSC and Charles Bowen, Ph.D. of Lockheed Martin for review.

For our sixth aim, we have purchased and received polysomnography and psychomotor vigilance task equipment. Setup, testing, and calibration of this equipment has been initiated and will be completed prior to the start of our second experiment. This equipment will not be needed for the first bench-marking experiment.

Finally, for the seventh aim, extensive discussions have been held between TJU's LRP and the extramural collaborators concerning a multiyear plan for the development and testing of specific lighting technologies that can be installed in the CEV and other space exploration habitats for acutely enhancing astronaut and ground crew alertness. The specific experiments, experiment sequence, and technology development will be determined once data is available from the first two studies.

Aside from evidence of a breakdown in physical health, the effects of circadian disruption and sleep loss have long been known to have potentially dangerous behavioral effects. Mental fatigue, diminished alertness, loss of psychomotor coordination and decreased physical performance are all commonly found in individuals with sleep loss, sleep debt, or circadian misalignment. The impact of these dangers affects many industries, including transportation, manufacturing, communications, and medicine. It has long been a source of concern for the military, as well. Additionally, many people experience the same effects due to air travel across several time zones. The U.S. Air Force has supported our laboratory in the past to study the acute alerting effects of light (French, et al., 1990; Brainard, et al., 1996).

A number of existing therapeutic interventions using light stand to benefit from enhancing our understanding of how different wavelengths of the spectrum affect human circadian and neurobehavioral regulation. A more efficient intervention with increased potency and/or fewer side-effects could result. One such disorder currently being treated with bright white light is Seasonal Affective Disorder (SAD), also known as winter depression. It is estimated that as many as 1 in 5 Americans suffer from SAD or its milder version, subsyndromal Seasonal Affective Disorder (sSAD) (Lam and Levitt, 1999). Similar bright white light interventions are also used for treating jetlag. Side effects from exposure to bright white light for this and other therapies include: hypomania, headache, vision problems, nausea, dizziness, and anxiety. Optimizing the light spectrum for specific affective and/or circadian-related disorders could deliver the same medical impact with lower levels of light intensity, and potentially fewer side-effects. Our group has initiated Phase I testing of light therapy with blue solid-state lighting for SAD patients (Glickman, et al., 2006).

For this project, we are collaborating with Apollo Light Systems, Inc., an NSBRI industrial partner, to develop a large panel of blue LEDs to serve as the independent variable in our first two experiments. Working closely with Apollo, we have modified the original prototype so it can be adjusted to provide a broad range of light intensities with no change in spectral output. Our laboratory has thoroughly characterized the prototype’s radiometry and photometry and it is now ready for use in our first two experiments.

Dr. David Sliney, a key collaborator on this project, has made a series of radiometric measurements of the prototype and has provided an independent safety analysis based on criteria from the American College of Government and Industrial Hygiene (ACGIH) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). His draft report confirms that the blue solid-state prototype operates “at all wavelengths and emission levels that are far below limits that are recognized as maximal safe exposure values.” Once finalized, the report will be distributed to James Maida at JSC and Charles Bowen, Ph.D. of Lockheed Martin for review.

This progress enables the initiation of the first experiment, a bench-marking study to characterize the biological potency of the prototype light. The study employs a within-subjects light-induced melatonin suppression protocol with healthy men and women. The study is approved by Jefferson’s IRB, and subject recruitment has been initiated. This study will be completed during the coming year and will have two important outcomes: it will help characterize the biological efficacy of the prototype light source relative to other light sources previously studied in our lab, and it will guide light intensity selection for the second experiment on the effect of blue light on alertness.

Our laboratory has acquired polysomnography and psychomotor vigilance task equipment for studying the alerting characteristics of this prototype light source. Although not needed for the first bench-marking experiment, setup, testing, and calibration of this equipment has been initiated and will be completed prior to the start of the alertness experiment. During the coming year, the alertness protocol design will be completed and a separate IRB covering that work will be submitted. Once IRB approval is granted, the study will be initiated.

8th International Congress of Physiological Anthropology, October 2006. , Oct-2006

2nd CIE Expert Symposium on Light and Health, September 2006. , Sep-2006

72nd Cold Spring Harbor Laboratory Symposium: Clocks & Rhythms, May 2007. , May-2007

Proceedings of the 2nd CIE Expert Symposium, 2006, p. 6-21. , Sep-2006

This is a new, directed research project. To initiate the work, we proposed the following seven aims:

1) Assemble a team of investigators who will create a set of study designs to be run from 2006 to 2012.

2) Establish either collaborative, consultant or subcontract agreements for elements of the work which are best done outside of Thomas Jefferson University (TJU).

3) Write and secure Institutional Review Board (IRB) approval of the first study design.

4) Design and fabricate the initial solid-state light sources for testing. These sources will serve as the independent variables in the initial study design.

5) Have an independent safety analysis completed on the solid-state lighting prototypes.

6) Purchase and calibrate equipment for assessing alertness and cognitive performance in the study volunteers.

7) Develop a multiyear plan for the development and testing of specific lighting technologies that can be installed in the CEV and other space exploration habitats for acutely enhancing astronaut and ground crew alertness.

Towards accomplishing the first two aims, written correspondence, phone calls and direct meetings were used to establish the team of investigators. Over the first year, a total of eight meetings were held: five meetings at TJU in Philadelphia, one in League City during the NASA Human Research Program Investigators Workshop, one at the External Advisory Committee meeting in Houston, and one at Johnson Space Center (JSC). As a result of these meetings, key collaborators who have formally agreed to participate on this project. These include James Maida of JSC's Habitability and Human Factors Branch; Charles Bowen, Ph.D. of Lockheed Martin's Human Factors Design team; David Dinges, Ph.D. and Namni Goel, Ph.D. from the University of Pennsylvania; Stephen Lockley, Ph.D. of Brigham and Womens Hospital and Harvard Medical School; David Sliney, Ph.D. of the U.S. Army Laser/Optical Radiation Program at Aberdeen Proving Ground; and Mark Rollag, Ph.D. of the University of Virginia. These collaborators will work with scientists and staff of TJU's Light Research Program (LRP) towards accomplishing the goals of this project. The collaborators will work on selected aspects of this project as per their expertise.

Progress towards the third aim involves the development of two experiments. Subject recruitment for the first experiment will be initiated during this month (the end of the first funding year) and the study will be completed in the second funding year. The second experiment will be initiated and run during the second year. The first experiment is a bench-marking study to characterize the biological potency of the prototype solid-state light source that is described below. A within-subjects, acute light-induced melatonin suppression study will be done with eight healthy men and women. This study will have two important outcomes. First, it will help characterize the biological efficacy of the prototype solid-state light source relative to monochromatic and polychromatic light sources previously studied in our lab. In addition, it will guide the selection of the light intensity that will be tested in the second study, which will focus on alertness. The IRB for the first study has been approved by TJU. The protocol for the second experiment, a two-day study on the alerting effects of blue light, is still being refined. Once the experimental design is completed, a separate IRB covering that work will be written and submitted for review.

Progress towards the fourth aim involves our collaboration with Apollo Light Systems, Inc., an industrial partner of NSBRI. Apollo has donated engineering time and materials to develop a large panel of narrowband blue LEDs. This light source will be the independent variable in the first two experiments discussed above. Working closely with an engineer from Apollo, we have modified the original prototype so it can provide a broad range of light intensities with no change to spectral output. Jefferson's LRP staff has thoroughly characterized the prototype radiometry and photometry. This light unit is now completely serviceable for experimental use.

Concerning our fifth aim, David Sliney, Ph.D. of Aberdeen Proving Ground has made a series of radiometric measurements of the prototype and has provided an independent safety analysis based on criteria from the American College of Government and Industrial Hygiene (ACGIH) and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). His draft report confirms that the blue solid-state prototype operates "at all wavelengths and emission levels that are far below limits that are recognized as maximal safe exposure values." Once finalized, the report will be distributed to James Maida at JSC and Charles Bowen, Ph.D. of Lockheed Martin for review.

For our sixth aim, we have purchased and received polysomnography and psychomotor vigilance task equipment. Setup, testing, and calibration of this equipment has been initiated and will be completed prior to the start of our second experiment. This equipment will not be needed for the first bench-marking experiment.

Finally, for the seventh aim, extensive discussions have been held between TJU's LRP and the extramural collaborators concerning a multiyear plan for the development and testing of specific lighting technologies that can be installed in the CEV and other space exploration habitats for acutely enhancing astronaut and ground crew alertness. The specific experiments, experiment sequence, and technology development will be determined once data is available from the first two studies.

Although the studies being considered in this project are focused on developing a non-pharmacological lighting countermeasure for space exploration, it is anticipated that there also will be significant benefits to civilians living on Earth. A significant portion of the global population suffers from chronic sleep loss and/or circadian-related disorders. Evidence for disease or illness occurring due to a disruption of circadian homeostasis has mounted significantly in the past several years. In the United States, 20 million Americans do shift work which interferes with a biologically healthy nocturnal sleep cycle (U.S. Congress OTA, 1991). This group has been shown to be more likely to suffer from a wide variety of ailments, including cardiovascular disease, gastrointestinal distress, cognitive and emotional problems. Furthermore, recent epidemiological studies of female night-shift nurses have shown that they are statistically more likely to suffer from breast cancer and colon cancer compared to day shift workers. Our laboratory is involved in testing the hypothesis that exposure to light at night is a risk factor for cancer (Blask, et al., 2005).