Individualized Real-Time Neurocognitive Assessment Toolkit for Space Flight Fatigue
Mathias Basner, M.D., Ph.D., M.Sc.
University Of Pennsylvania
This project addresses the NSBRI Human Factors and Performance Team goal to develop tools to assess crew performance in real time and evaluate countermeasures to mitigate the effects of fatigue, circadian misalignment and work-overload. It has secondary relevance to the Neurobehavioral and Psychosocial Factors and Sensorimotor Adaptation Teams. It is responsive to the critical need to identify how a range of cognitive functions of astronauts can be affected in spaceflight by fatigue alone, its interaction with other risk factors and conditions (e.g., elevated CO2, intracranial pressure, space fog), and countermeasures.
The project will deliver a comprehensive, software-based, neurocognitive toolkit. By building on state-of-the-art neuropsychological test development, the toolkit will permit evaluation of a full range of cognitive functions using brief (1-5 minutes), validated procedures. The tests include -- but go beyond -- what is currently measured by WinSCAT and the Reaction Self Test on the International Space Station (ISS). Importantly, the toolkit will permit rapid assessment of performance in cognitive, social-emotional and sensorimotor domains. Real-time performance assessment algorithms will be individualized to each astronaut's norm, and adjusted for learning using a data modeling approach, in order to optimize individual and team performance relative to the effects of fatigue and related cognitive impacts. The toolkit will facilitate identification of underlying neural mechanisms affected when cognitive deficits are identified, by using tests selected on the basis of published fMRI studies that identify the specific brain regions subserved by each test.
Toolkit development will begin at Technology Readiness Level (TRL) 5/Cost Readiness Level (CRL) 6, and progress from laboratory, to space analog (NASA Extreme Environment Mission Operations), to ISS (TRL 7/CRL 8). The resulting comprehensive, neuroscience-validated, cognitive test battery for real-time evaluation of astronauts in space will be an essential detection technology for effective fatigue countermeasure management of astronaut performance in space. The link to neuroscience will yield directions for mechanisms of cause and potential interventions.
1) Development of short-duration adaptive versions of CATS neuropsychological tests for spaceflight.
2) Establish learning curves for CATS neuropsychological tests and validate sensitivity to sleep deprivation.
3) CATS Toolkit software development and optimization for spaceflight
4) JSC field testing, astronaut learning curves, and astronaut norms for performance feedback algorithm development.
5) International Space Station (ISS) feasibility study.
New items for the Matrix Reasoning Test were developed and tested for their usability in an adaptive version of the test. The Conditional Exclusion Test was replaced by the Abstraction and Working Memory (AIM) Task, as the latter is more suitable for repeated administration. We published a paper on an adaptive duration version of the PVT, and the same methods can be applied to many of the NeuroCATS tests after baseline data for astronauts are available.
Using already existing test versions, the 10 NeuroCATS tests were inserted into two sleep-restriction protocols currently underway at the University of Pennsylvania. Thus far, the researchers recorded 290 full-test batteries in 19 subjects. They wrote a specific software that visualizes test data immediately after acquisition.
One important finding from these tests completed so far is that, after some initial training, NeuroCATS administration takes less time than expected (ca. 30 min for the whole battery). The current test software will be replaced by the CATS Toolkit software in year 2 of the protocol. Excellent progress was made in developing the CATS toolkit software platform and integrating already existing and newly developed tests. The first full version will be launched in the beginning of Year 2 and deployed both in the laboratory studies at the University of Pennsylvania (Aim 2) and in the astronaut study at JSC (Aim 4). The Conditional Exclusion Task was replaced with another abstraction task (AIM, Glahn et al.,1999) with higher suitability for repeated administration. In this process, 1,000 AIM stimuli were piloted in 16 students. Instead of participating in three NEEMO missions, they are planning to have N=20 astronauts or astronaut candidates perform the NeurCATS battery 15 times to start building a normative data base, and to establish learning curves and gather astronaut feedback for each NeuroCATS test.
Impact of Key Findings on Hypotheses, Technology Requirements, Objectives and Specific Aims of the Original Proposal
The researchers were not able to get access to astronauts in NEEMO, and accordingly changed Aim 3 with NSBRI approval. They will now investigate astronauts and astronaut candidates while preparing for missions at JSC. Data from their laboratory studies showed that the Conditional Exclusion Test is not adequate for repeated administration. It was thus replaced by the AIM, which taps into the same cognitive domain (abstraction).
Proposed Research for the Coming Year
The development of adaptive and/or shorter versions of the individual NeuroCATS tests will continue in Year 2. In the sleep restriction studies running at the University of Pennsylvania, the current NeuroCATS software will be replaced with the CATS toolkit software. Data acquisition at JSC (N=20 astronauts) is projected to start in Year 2 of the protocol. Based on the findings of this study, the battery will be refined and finalized before operational testing on ISS starts in Years 3 and 4 of the protocol.