Field Study Evaluation of Cepstrum Coefficient Speech Analysis for Fatigue in Aviation Cabin Crew

Details

• Creators:
  Greeley, H.P. ; Roma, P.G. ; Mallis, M.M. ; Hursh, S.R. ; Mead, A.M. ; Nesthus, T.E.
• Corporate Creators:
  Institutes for Behavior Resources ; Response Applications, LLC ; Civil Aerospace Medical Institute
• Subject/TRT Terms:
  • Field studies
  • Behavior
  • Speech
  • Fatigue (Physiological condition)
  • Flight crews
  • Performance tests
  • Human subject testing
  • Neurology
  • Reaction time
  • Aviation safety
  More +
• Publication/ Report Number:
  DOT/FAA/AM-13/19
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  United States. Office of Aerospace Medicine
• Abstract:
  Impaired neurobehavioral performance induced by fatigue may compromise safety in 24-hr operational ; environmentssuch as aviation. As such, non-invasive, reliable, and valid methods of objectively detecting ; compromised performance capacity in operational settings could be valuable as a means of identifying, ; preventing, and mitigating fatigue-induced safety risks. One approach that has attracted attention in recent ; years is quantitative speech analysis, but the extent of its operational feasibility, validity of the metrics, and ; sensitivity to operationally-relevant factors in aviation remains unknown. To this end, the present report offers ; an initial proof-of-concept evaluation of a speech analysis method based on Cepstrum Coefficient modeling, ; using voice files from a broad sample of 195 cabin crew personnel collected during the 2009-2010 U.S. Civil ; Aerospace Medical Institute-sponsored Flight Attendant Field Study (Roma et al., 2010). ; Using a personal digital assistant device, participants recited five standardized phrases in random order ; before and after each workday and sleep episode throughout their respective 3-4 week study periods. ; Operational acceptability of the procedure was high, as indicated by high protocol compliance and, despite the ; inherent variability of the timing and environments in which the test sessions occurred, the 13,975 files from ; 2,795 valid sessions were of sufficient quality for formal analysis. Individualized “baseline” speech models ; were built from the files collected during test sessions coinciding with optimal neurobehavioral performance, ; as determined by 5-min Psychomotor Vigilance Test (PVT) reaction times(RT), then speech deviation scores ; relative to individual baseline models were calculated for the test sessions that preceded and concluded each ; “trip” of multiple consecutive work days. Regarding validity, speech scores correlated significantly with PVT ; RTs and Lapses(RTs > 500 msec), with a stronger relationship to Lapses, but high variability at the low range ; of both performance variables suggests the influence of other factors. Regarding sensitivity to operational ; factors, average Pre-Trip vs. Post-Trip speech scores differed significantly, although scores unexpectedly ; decreased from Pre to Post, an artifact attributable to the composition of the baseline session pool. ; Nonetheless, the pattern of speech data echoed performance data from our previous report in which scores ; were most affected in crew of Regional carriers, with Junior seniority, and in Domestic operations. ; These initial results reveal promising validity and sensitivity of Cepstrum Coefficient modeling for speech ; signal analysis of fatigue in dynamic operational environments. Remaining questions underscore the need to ; further explore the dataset to determine the precise relationship between speech production and ; neurobehavioral performance capacity, the parameters for constructing individualized models, and ; standardized quantitative speech-based definitions of fatigue.
  More +
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/26637/dot_26637_DS1.pdf
• File Type:
  [PDF - 1.24 MB]
• Collection(s):
  FAA Civil Aerospace Medical Institute ; US Transportation Collection
• Main Document Checksum:
  urn:sha256:c8c04c75ce291eb4d14deca2695312b65c87d601e579a90fd7ff1b2dd5d40aeb