Task Effects of Long-duration Microgravity on Fine Motor Control Skills
Last Published:  07/31/19 10:05:33 AM (Central)
Short Title: Fine Motor Skills
Responsible HRP Element: Human Factors and Behavioral Performance
Collaborating Org(s):
Funding Status: Active - Currently funded and in progress
Procurement Mechanism(s):

Fine motor skills will be critical during long-duration space missions, particularly those skills needed to interact with new technologies required for autonomous operations in next generation space vehicles, spacesuits, and habitats.

The specific aims of this investigation are:  

  1. Determine the effect of long-duration microgravity on fine motor performance.
    • How does fine motor performance in microgravity trend/vary over the duration of a six-month and year-long space mission?
    • How does fine motor performance on orbit compare with that of a closely matched subject on Earth?
  2. Determine the effect of different gravitational transitions on fine motor performance.
    • How does performance trend/vary before and after gravitational transitions, including the periods of early flight adaptation, and very early/near immediate post-flight periods?

Results of this study are based on two crewmembers (one U.S. astronaut and one Russian cosmonaut) and one ground-matched subject completed the Fine Motor Skills study as part of the first ISS one-year mission (1YM). Seven standard duration (6-month) United States Orbiting Segment (USOS) crewmembers, and seven ground-matched subjects also completed the study. Additionally, ground subjects were recruited through the JSC Human Test Subject Facility and were matched for age, education, vision, hearing, and fitness level. Their schedule of participation was lagged by a number of weeks in order to match the flight schedule as closely as possible (i.e., to adjust for late-breaking onboard crew schedule changes). 

Data collection for all subjects was done weekly through the first 3 months, with collection every 14 days for the rest of the mission. Data were also collected early and late in flight, and on landing day out to 30 days post-landing. All subjects were scheduled to perform their sessions within 4 hours of waking, and asked to avoid strenuous exercise involving the hands prior to the session.

Data analysis of the Fine Motor Skills test battery dataset was done using a performance metrics for the Pointing, Dragging, and Tracing task. A prior data set from a previous ground study of 33 subjects was used in the creation of this metric. The dataset was from a broader subject pool (i.e., not only crew-like subjects), but included enough data upon which to build robust response-time distributions (Pointing and Dragging tasks), or a response-time vs accuracy joint distribution (Tracing Task), which would provide a reference to which the current data could be applied. Full details of performance metric are available in the final report Holden, 2019.

Results of Aim 1: Determine the effect of long-duration microgravity on fine motor performance.

Results indicate that long-duration microgravity does not appear to have a significant impact on fine motor skills inflight (as assessed by simple tasks on a touchscreen). It is likely that if there is any detrimental effect, it is overcome by crew continuously exercising fine motor skills in the course of their mission. On a daily basis, they are interacting with the computers, iPads, and small controls to perform their job. A much more concerning impact was found with respect to the effects of gravitational transitions.

Results of Aim 2: Determine the effect of different gravitational transitions on fine motor performance.

The analysis of aim 2 focused on phase comparisons involving gravitational transition: A) Preflight Baseline to Early Flight (first week), B) Late Flight (session 20+) to Early Postflight (R+0, R+1, and R+3), and C) Late Flight to Late Postflight (R+5, R+15, and R+30). The majority of statistical tests reported are for comparisons of mean performance changes for astronauts vs. those for ground controls over the phase transitions A, B, C, above.
Performance on the Pointing, Dragging, and Shape Tracing tasks all showed significant decrements the first week in microgravity, as compared to ground controls. This is not surprising since we know that the body undergoes a significant adaptation period when transitioning to microgravity, after launch. In this early adaptation period, there is some degree of space sickness, and new skills to learn: how to move, how to stop, and how to remain still to perform tasks. The present results demonstrate that the gravitational transition disrupts fine motor performance as well, and once crew adapt, their performance improves.

Integration/Unique Aspects:

This study will data share with several other investigators – e.g, Functional Task Test (HHC), Field Test (HHC), Sleep, Neuromapping, Cognition. This investigation also has a data sharing agreement with Roscosmos RSC Energia and GCTC.