Document Description

Document Citation

Effects Of Sleep Loss On Team Decision Making.
Archival Document: Yet Another Sleep Dep Study

Authors: Pre Mizdrak, NTT SYSTEMS INC
Marc S. Grushcow, NTT SYSTEMS INC
Collaborators: Bob Le, NTT

Bibliographic Citation (APA)
Mizdrak, P. and Grushcow, M.S. (2003) Effects of Sleep Loss on Team Decision Making. Defence Research and Development Canada - Toronto.

Version Information
March 27, 2003
This version was created primarily as a test of the experiment description editor. It should not be taken to represent the work that was actually done.

Version 1.1 -- August 19, 2003 (Marc Grushcow)
Removed a variety of information included solely for application testing.

Study Description

Study Citation

Effects of sleep loss on team decision making:
Yet Another Sleep Dep Study

Authors:J. Smith, Some Scientific Lab
Collaborators:M. Thomas, Some Scientific Lab
F. Listz, Some Scientific Lab
L. Pasta, Some Scientific Lab
C. Bottle, Some Scientific Lab
V. Gills, Some Scientific Lab
R. TheBoss, Some Scientific Lab
Contributors:Andy Haws, Some Scientific Lab, Support Manager,
Heath Fine, Some Scientific Lab, Controller,
Tony Stokes, Some Scientific Lab, Analyst,

Bibliographic Citation(APA)
Smith, J., Thomas, M., Listz, F., Pasta, L., Bottle, C., Gills, V., TheBoss, R. (2002) Effects of Sleep Loss on Team Decision Making. Defence Research and Development Canada - Toronto

Overview

Study Scope

Abstract

We examined the effects of 30 hours of sleep loss and continuous cognitive work on performance in a complex and interactive team decision-making environment. Sixteen teams participated, each comprised of four members. Three team members made independent threat assessments on a medium fidelity simulation of a naval surveillance and threat assessment task and then forwarded their judgments electronically to a team leader who made a final assessment on behalf of the team. The performance loss associated with fatigue due to sleep loss was mediated by being a member of a team.

Subject Classification

Keywords:Sleep loss, fatigue, teams, decision making, social loafing, social facitation.
Topics:topic 1, topic 2.

Summary Description

Period of Interest
From:April 3, 2003
To:April 23, 2003
Date of Data Collection:August 19, 2003
Coverage Area:NA
Unit of Analysis:Individuals
Collected Data Types:Experimental Data, Census/Enumeration Data, Misc. other data types.
Respondent Nationality:Canada, United States, other.
Included Population:Healthy active service military personnel.
Excluded Population:Those who were not medication free for at least 1 week prior to the experiment, or had allergies or cardiovascular, neurological, psychiatric, or sleep related disorders

Summary Description Notes
SDN Subject (SDN Author)
summary descr notes

Introduction

(Smith, J)
Perhaps nowhere are the effects of sleep loss more poignant than in those occupations that combine long night shifts, isolation, and a strong vigilance or monitoring component (e.g., long-haul trucking, military watch, power plant and systems monitoring). Pragmatically, the extant laboratory-based scientific literature on the effects of sleep loss has focused almost exclusively on the performance of the individual (e.g., Angus & Heselgrave, 1985; Lisper & Kjellberg, 1972; Williams, Lubin, & Goodnow, 1959), often conducting repetitive, monotonous tasks with limited environmental stimulation (for reviews of various portions of this vast literature see Dinges & Kribbs, 1991; Harrison & Horne, 2000; Horne, 1988; Johnson, 1982; Kjellberg, 1977; Krueger, 1989; Pilcher & Huffcutt, 1996). In contrast, other important occupations require people to work effectively together for long periods of time and at all hours of the day or night (e.g., police, fire fighters, emergency medical services, and military command teams). More generally, the increasing prevalence of work teams in contemporary society (Goodman, Devadas, & Hughson, 1988; Hackman, 1986; Swezey & Salas, 1992), coupled with ever increasing productivity demands, has provided a need to better understand how fatigue due to sleep loss might affect the performance of teams as opposed to individuals.

More comments and background material goes here.

A potentially important aspect of Hoeksema-van Orden et al.s (1998) experiments is that their subjects were not performing their cognitive tasks in a traditional team context. Rather, subjects completed all tasks entirely independently of each other and their collective performance was based upon the sum of their individual scores. Thus, in both experiments, participants completed their tasks coactively rather than cooperatively, the latter feature considered a defining hallmark of team tasks. Although clearly some team tasks do not require any cooperation, one of the main reasons that teams are formed is precisely because the demands and complexity of the task at hand requires people to work collaboratively.

Hypotheses

(msg)
The main objective of the present research was to extend results reported by Hoeksema-van Orden et al. (1998) to a more traditional team task context. In addition, we also sought to further elucidate conditions that may moderate various strategies. We approached the problem in several ways. First, following on the results of Hoeksema-van Orden et al. (Experiment 2), we manipulated various conditions. Specifically, each team participated in three conditions in which the performance of each team member was disclosed in various way

  1. Sleep Effect (Smith, J)
    Performance will decay with sleep loss.

  2. Social Loafing (Listz, F.)
    Subjects who have access to information about their team mates' performance will be less accurate when team performance is high.

References

  1. Angus, R.G., & Heslegrave, R. J. (1985). Effects of sleep loss on sustained cognitive performance during a command and control simulation. Behavioral Research Methods, Instruments & Computers, 17, 55-67.
  2. Baranski, J. V., Gil, V., McLellan, T., Moroz, D., Buguet, A., & Radomski, M. (2002). Effects of modafinil on cognitive performance during 40 hours of sleep deprivation in a warm environment. Military Psychology, 14, 23-48.
  3. Babkoff, H., Caspy, T., Mikulincer, M., & Sing, H. (1991b). Monotonic and rhythmic influences: A challenge for sleep deprivation research. Psychological Bulletin, 109, 411-428.
  4. Babkoff, H., Caspy, T., & Mikulincer, M. (1991a). Subjective sleepiness ratings: The effects of sleep deprivation, circadian rhythmicity and cognitive performance. Sleep, 14, 534-539.

Ethics Approval (Reference: X-345)

Ethics approval was granted in accrodance with a submission made in March 1999.

Ethics-LFCA.doc

Method

Subjects

Demographics
Sixty-four adults (mean age = 21.7) each served for 60 hours of experimental participation in return for (approximately) $XXX.XX. Subjects participated in 4 member teams: Eight teams were comprised of military personnel recruited by advertisement from Toronto area; eight teams were comprised of civilians recruited by advertisement from Toronto area universities1. All subjects were classified as fit to participate if they met the following criteria: (a) were healthy, (b) were medication free for at least 1 week prior to the experiment, and (c) had no allergies or cardiovascular, neurological, psychiatric, or sleep related disorders. All subjects were fully informed about the procedures to be employed, signed informed consent forms for participation, and were given a full debriefing upon completion of the study.

Subject List
Subject Experiment IDSubject Internal Reference
X43a101
yy56102

Apparatus

(Haws, A)
The experiment was conducted in the DRDC-Toronto sleep deprivation research facility.

Facilities

The experiment was conducted in a closed facility consisting of an control room, four subject work rooms, a kitchen, eating area,lounge and washroom with shower. The lounge was equipped with a TV and VCR.

  1. Subject Rooms(me yet again)
    Each subject worked in a room approximately 10' square.

    ComputerA Workstation class computer equipped as described.
    BedStandard cot style
    IntercomUsed for communications between the subject and the experimenters
    Video cameraUsed to monitor subjects during work sessions

  2. Control RoomThis was used by the researchers and support staff to monitor the experiment.

    IntercomUsed for communication between the monitors and the subjects
    MonitorsOne slaved to each subject monitor.
    TV MonitorsOne connected to the video camera in each subject room.
    ComputerSUSOPS experiment control computer.

Computers and Software

  1. There were 4 500MHz PIII computers configured as Workstations each equipped with a 15'' 800x60096 dpi monitor.

    In addition, the following software was installed:
    NameVersion Note
    TITAN2.0This is a decision-making task software.
    Windows 98SEApplied SR-2

  2. There was 1 700MHz PIII computer configured as a Server equipped with a 17'' 1024x768120 dpi monitor.

    The following additional equipment was in place:
    TypeDescription
    bedeach subject room was equipped with a bed
    intercom used for communication between experimenters and subjects (
    4 slave monitorsused for monitoring subjects' performance online
    4 slave monitorsused for observing subjects through the closed circuit cameras

    In addition, the following software was installed:
    NameVersion Note
    Susops2.0Tasks were chosen and dispatched from this machine.

Data Acquisition

  1. Embla (Mfgr: Flaga hf, Iceland, Model: Embla)
    Eight channels of electropshysiological recording (including EEG, EOG, EMG, and EKG) were collected continously using this data recorder.

    Channel IDData TypePlacement/Comments
    EEG1EEGC3
    EEG2EEGC4
    EEG3EEGO1
    EEG4EEGO2
    ECG1ECG
    ECG2ECG
    ECG3ECG
    EMG1EMG

  2. Actigraph (Mfgr: Actigraph, Model: N/A)
    These were used as backup for the EEG recordings.

  3. digital thermometers (Mfgr: DigiThermo, Model: DT201)
    Channel IDData TypePlacement/Comments
    N/AOral TemperatureMeasurements taken every two hours

Design

(Smith, J)
Subjects arrived at 0800 on day 1 of the study and departed at (approximately) 1700 on day 3. Upon arrival on day 1, subjects were familiarized with the lab, were assigned rooms, were briefed on the experiment, and signed informed consent forms. All time cues were then removed (e.g., watches, cell phones, pagers) and a team leader was selected (based on rank and years of experience for military teams and on age for civilian teams). Subjects then filled out computer-based questionnaires (e.g., demographics, general health, and sleep habits) and a number of scales concerning personality, cognitive, and group styles.

All foods and beverages containing caffeine were terminated at 1200 of day 1. They were outfitted with monitors and had a dinner break. There was an evening practice run then subjects relaxed and went to sleep.

Naps and various team activities were scheduled on later days. An example of a 2-block period (i.e., 4 hours) is provided in the "Schedules" section below. The entire experiment was scripted into an automated task delivery system that permitted precise control of task timing.

Independent Variables

Within Group Factors

  1. Feedback Level ((Within) (Smith, J)
    Levels:Full feedback, Partial feedback, No feedback.
    Feedback was used as a within group factor

  2. Session
    Levels:Day 2 0800-1100, Day 2 1200-1500, Day 2 1600-1900, Day 2 2000-2300, Day 3 0000-03000, Day 3 0400-0700, Day 3 0800-1100.
    This factor reflects the effect of fatique due to sleep loss.

Between Group Factors

  1. Feedback Level (Between) (Smith, J)
    Levels:YES, NO.
    Another feedback rule was used between groups.

  2. Team type (Pasta, L.)
    Levels:Type A, Type B.
    There was an equal number of teams of each type.

References

  1. Angus, R.G., & Heslegrave, R. J. (1985). Effects of sleep loss on sustained cognitive performance during a command and control simulation. Behavioral Research Methods, Instruments & Computers, 17, 55-67.

Procedure

Schedules

  1. Experiment ScheduleOverall Schedule (Smith, J)
    These notes go with "Experiment Schedule"

    From: To: Activity :
    0 08:000 09:00Subjects arrive
    0 09:000 10:00Computerized Questionnaites
    0 10:000 11:00Training on Psychomotor Battery
    0 11:000 12:30Training on Titan Task
    0 13:000 13:30Practice Titan Task
    0 13:300 17:00Training on Higher Level Cognitive Tasks
    0 17:000 19:00Electrode Application
    0 19:000 21:00Practice Experimental Block
    0 22:001 06:00Basline Sleep
    1 08:001 09:45Cognitive Testing
    1 10:001 11:45Cognitive Testing
    1 12:001 13:45Cognitive Testing
    1 14:001 15:45Cognitive Testing
    1 16:001 17:45 Cognitive Testing
    1 18:001 19:45Cognitive Testing
    1 20:001 21:45Cognitive Testing
    1 22:001 23:45Cognitive Testing
    2 00:002 01:45Cognitive Testing
    2 02:002 03:45Cognitive Testing
    2 04:002 05:45Cognitive Testing
    2 06:002 07:45Cognitive Testing
    2 08:002 09:45Cognitive Testing
    2 10:002 11:45Cognitive Testing
    2 12:002 12:30Pre Nap Titan Task
    2 13:302 15:30Nap
    2 15:302 16:00Post Nap Titan Task
    2 16:002 17:00Debrief & Remove Electrodes

  2. Sample Two Hour Block
    From: To: Activity :
    08;0008:24TITAN TITAN (Full Feedback)
    08:2508:29Team TITAN questionnaires, NASA TLX
    08:3008:54High-Level Cognitive Task - Spatial Deductive Reasoning
    08:5509:19TEAM TITAN (Partial Feedback)
    09:2009:25Team TITAN questionnaires, NASA-TLX
    09:2609:40Psychomotor Task Battery
    09:4110:00Break
    10:0010:24TEAM TITAN (No Feedback)
    10:2510:29Team TITAN questionnaires, NASA-TLX
    10:3010:54High-Level Cognitive Task - Medical Diagnosis task
    10:5511:19SOLO TITAN
    11:2011:25NASA-TLX
    11:2611:40Psychomotor Task Battery
    11:4112:00Break

Results

(Smith, J)
The results are presented in three major sections. The first provides data concerning level of fatigue experienced by participants, including sleep physiology, temperature ratings, and self-assessments of subjective fatigue. The second examines the effects of the various feedback manipulations on team performance during sleep deprivation. The final section specifically examines the effects of fatigue in the TITAN task environment.

Dependent Measures

Sleep Measure

Units:min
Analyses of sleep physiology measures (Rechtschaffen & Kales, 1968) for the first night were conducted for 52 of the 64 subjects for whom full data sets were available. Sleep measures investigated were: time in bed, total sleep time, sleep efficiency, sleep latency, %wakefulness, Stage 1%, Stage 2%, Slow wave sleep%, REM%, movement time, awakenings, arousals, and sleep stage changes. Information about analysis techniques and results go here ...

Performance Measure (processing time)

Units:sec
The ANOVA conducted on mean processing time likewise revealed a highly significant effect of Sessions. Finally, no other main effects or interactions approached significance, including the critical interaction between feedback conditions.

Performance Measure (error)

Units:percent correct
The ANOVA on the assessment accuracy measure revealed a highly significant main effect of Sessions. Accuracy first improves with practice, reaching a peak by the late afternoon of day 2 (recall that by this time teams have completed over 12 TITAN sessions, not including practice on day 1). So on, and so forth ...

Fatigue Measure

Oral temperatures and Stanford Sleepiness scores (Hoddes, Zarcone, Smythe, Phillips, & Dement, 1973) were obtained from each participant during the Psychomotor Task battery (i.e., every 2 hours) throughout the formal experiment (i.e., 0800 on day 2 to 1200 on day 3), for a total of 14 observations per subject. Temperature is a traditional circadian measure related to fatigue (e.g., Babkoff, Caspy, Mikulincer, & Sing, 1991b; Froberg, 1977; Monk, 1991) and the Stanford Sleepiness Score is a standardized sleepiness index, employed routinely in sleep loss and performance studies (see Babkoff, Caspy, & Mikulincer, 1991a). The scale ranges from 1 ("Feeling active and vital; alert; wide awake") to 7 ("Almost in reverie; sleep onset soon; losing struggle to remain awake"). The results display ...

Conclusions

Social Loafing (Smith, J)

The present findings suggest that the effects of fatigue due to sleep loss on team performance may depend on various factors. In non-interdependent tasks, certain behaviours will be accentuated by fatigue. In interdependent tasks, in which individual level performance feedback is provided, some things may enhance team performance over individual level performance. Moreover, the effects of other factors, as seen in the different feedback conditions of the team task, may mitigate the effect in instances where compensatory behaviours... In real world situations then, these results suggest a potentially useful countermeasure in team contexts where fatigue may exist.

Experiment Data

Collected Raw Data

You can put general information about the raw data files here. Also, a link is available for an external document.

Week 1 Practice Data

PractWk1.zip
File Ref. ID:sfgsdfg
File Type:Raw Data Archive
Format:binary
Software:WinZipZip (8.0)
Data collectedfor subjects 11a, 11b, and 11cduring the first run.

No practice data for the leader is available.

General Note About File Descriptions.
There is "note" space available for each file description.

Missing Data and Remedies

Data was missing for the following subjects and situations. This section also describes what we did to deal with the missing data in our analyses. There is a link that can be used to display an external document. ...

Data Cleaning Procedures

All psychomotor task data was cleaned up and preprocessed for analysis in accordance with our standard procedures.

preparing data files for anlaysis using jmp.doc

Clean Data Files

The data from the psychomotor tasks and questionnaires is converted into JMP files where segments can be easily extracted for investigation.

Titan Team Data

st team data-new (trim 1)(1).jmp
File Type:JMPSpreadsheet
Software:JMP (??)
Data from all Team TITAN runs after the basic data points have been calculated by the TITAN Log Analyzer.

SRT Data

srt11L.JMP
File Type:JMPSpreadsheet
Software:JMP (?)
SRT data from all runs over the entire experiment.