A Psychophysiological Investigation of the State of Monotony amongst Air Traffic Controllers ICRAT 2004, Zilina Sonja Straussberger, Wolfgang Kallus & Dirk Schäfer

Introduction Straussberger, S., Kallus, W. & Schäfer, D. Today’s talk Relevance of Monotony for Air Traffic Controllers The Concept of Monotony Results of an Experimental Study ICRAT 2004, Zilina

Introduction Monotony in ISO Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina INDIVIDUAL WORK ENVIRONMENT Mental Stress Mental Strain ActivationWarming-up Mental fatigue Monotony Reduced vigilance Mental satiation Facilitating Effects Impairing effects

Introduction What needs to be considered? - Ill-defined and mixed terms Monotony (e.g., McBain, 1970) Boredom (e.g., Mikulas & Vodanovich, 1993) Underload (e.g., Young & Stanton, 2002) - Contributing factors? Task Characteristics (e.g. Pfendl, 1985) Personality Factors (e.g. Hill, 1975) Situational Factors (e.g. Marvje & Horne, 1994) - Short-term and long-term impairments (e.g., Thackray, 1975; Kass, Vodanovich & Callender, 2001) Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Introduction What is a State of Monotony? Bartenwerfer’s concept of Monotony (1960, 1985): - Specific consequence in situations when continuous engagement in a restricted task is required - Tasks may be characterized by low stimulation, high repetition, low difficulty level, longer time on Task - Impacts on physiological, subjective and performance level Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Introduction Research Questions In simulated Air Traffic Control– depending on repetitiveness and dynamic density (DD) in traffic … …is there a difference in physiological indicators for a state of monotony …is there a difference in subjective indicators for a state of monotony in Air Traffic Controllers? Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Methods Straussberger, S., Kallus, W. & Schäfer, D. Experimental Design 2 (Break Activity) x 2 (Repetitiveness) x 2 (Sequence of DD) x 2 (Run) x 3 vs. 15 (Interval)-Mixed Design ICRAT 2004, Zilina Break Activity activenon active Repetitiveness repetitivenon repetitive non repetitive DD Run 1lhlhlhlh Run 2hlhlhlhl Break Run 3 n n total24 DD=Sequence of Dynamic Density in Traffic (high (H) - low (L) vs. H (High) – L (Low))

Methods Operationalization of Repetitiveness & Dynamic Density Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Methods Physiological Measures: mean HR, mean HRV in 3-minute-intervals during scenarios Subjective State : During Scenario: attentiveness, fatigue, boredom, irritation, strain, concentration, motivation, sleepiness (TSI, Thackray et al., 1975; 7-point-rating-scale; ext.) After Scenario: Mental demand, physical demand, temporal demand, performance, effort, frustration, overall workload (NASA- TLX, Hart & Staveland, 1988) + feeling of monotony, SA Other measures collected Straussberger, S., Kallus, W. & Schäfer, D. Dependent Variables ICRAT 2004, Zilina

Results Physiological level: heart rate Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina Average corrected HR during first and second run for groups with non repetitive (n=12) and repetitive (n=12) traffic (Repetitiveness: F 1 =4.41, p=.05; Run: F 1 = 17.68, p=.001)

Results Physiological level: HRV Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina Average HRV during first and second run for groups with non repetitive (n=12) and repetitive (n=12) traffic (Repetitiveness: F 1 =7.52, p=.013; Run: F 1 = 24.98, p=.000)

Results Rating: “feeling of monotony” Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina Average ratings for feeling of monotony after first and second run as a function of repetitiveness and sequence of DD (Run x Repetitiveness: F 1 =8.83, p=.008; Run x Sequence: F 1 = 5.39, p=.031; Run x Repetitiveness x Sequence F 2 =10.57, p=.004)

Results Rating: “sleepiness” Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina Average change from baseline in perceived sleepiness during first and second run for groups with non repetitive (n=12) and repetitive (n=12) traffic (Run: F 1 =14.35, p=.001; Interval: F 2 =17.80, p=.000; Run x Sequence: F 1 =8.44, p=.009; Run x Interval x Repetitiveness: F 2 =5.83, p=.011)

Discussion Summary & Discussion -Supports for Theory of Monotony: physiological deactivation -Self-reports more complex -Consideration of impairing and facilitating effects -Implications for work design, work organization and controller selection Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

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Results Rating: “boredom” Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina Average change from baseline in perceived boredom during first and second run for groups with non repetitive (n=12) and repetitive (n=12) traffic (Repetitiveness: F 1 =9.24, p=.006; Interval: F 2 =17.87, p=.000; Run x Repetitiveness: F 1 =5.14, p=.035; Interval x Repetitiveness: F 2 =22.69, p=.000)

Results Rating: “motivation” Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina Mean ratings of motivation perceived boredom during first and second run for groups with non repetitive (n=12) and repetitive (n=12) traffic for each Sequence of DD from Run 1 to Run 2 (Run: F 1 =19.41 p=.000; Interval: F 2 =12.24, p=.000; Run x Sequence: F 1 =7.39, p=.013; Run x Repetitiveness x Sequence: F 1 =5.49, p=.03;)

Results Some more results: TXL TLX: -Mental demand higher for nrep; -Temporal demand remains higher for nrep, from Run 1 to Run 2 decrease stronger for h-l as increase for l-h -Performance rated higher from nrep -Effort rated higher from nrep Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Results Some more results: TSI TSI: -Attentiveness remains constant for repetitive (rep) group and decreases for non-repetitive (nrep) group -Fatigue higher for H-L group; higher von nrep in Run 1 and rep in Run 2 -Concentration decreases more for nonrep -Sleepiness: increased over time, but more in Run 2 for h-l Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Methods Participants 24 Enroute ATCOs 18 male, 6 female years Straussberger, S., Kallus, W. & Schäfer, D.ICRAT 2004, Zilina

Methods Straussberger, S., Kallus, W. & Schäfer, D. Procedure min 1.Welcome, Summary of Controller Handbook, open questions10 2.Preparation of physiological measures + Questionnaires40 3.Training 40 4.Baseline, Scales 5 5.Run Baseline, Scales30 7.Run Baseline, Scales30 9.Break with vs. without activity10 10.Run Baseline, Scales 5 12.Performance Tests15 13.Remove equipment 5 14.Debriefing10 Total Time295 Session Start 8:00 vs. 14:00 ICRAT 2004, Zilina

Methods Dynamic Density Straussberger, S., Kallus, W. & Schäfer, D. Traffic density (amount of AC) Traffic complexity –Heading Change –Speed Change –Altitude Change –Minimum Distance 0-5 n.mi. –Minimum Distance 5-10 n.mi. –Predicted conflicts 0-25 n.mi. –Predicted conflicts n.mi. –Predicted conflicts n.mi. (Controller intent) Laudemann et al. (1998) ICRAT 2004, Zilina

Methods Independent Variables Straussberger, S., Kallus, W. & Schäfer, D. - Repetitiveness (repetitive vs. non-repetitive conflict patterns) - Sequence of Dynamic Density in Traffic (high (H) - low (L) vs. H - L) - 2 Runs (1. Scenario vs. 2. Scenario) - (Time over Scenarios) - [Activity in Rest Break] ICRAT 2004, Zilina

Methods Further Variables Straussberger, S., Kallus, W. & Schäfer, D. Continuous Variables: -RSQ (Recovery-Stress-Questionnaire, Kallus, 1995) -ACS-90 (Action Control Strategy, Kuhl, 1992) -Boredom Proneness Scale (Farmer & Sundberg, 1986) -Morningness-Eveningness-Scale (Horne & Ostberg, 1976) -Big Five Markers (Goldstein, 1992,1999) Control Variables: -Initial State (FAL), age, sex, nationality, mother tongue, ratings for working position, experience, actual worked sector, handedness, body weight, body height, vision, smoking, time, room temperature, movement, respiration