title: Cusp catastrophe models for cognitive workload and fatigue in a verbally cued pictorial memory task.
abstract: OBJECTIVE
  The aim of this study was to evaluate two cusp catastrophe models for cognitive workload and fatigue. They share similar cubic polynomial structures but derive from different underlying processes and contain variables that contribute to flexibility with respect to load and the ability to compensate for fatigue.
  
  
  BACKGROUND
  Cognitive workload and fatigue both have a negative impact on performance and have been difficult to separate. Extended time on task can produce fatigue, but it can also produce a positive effect from learning or automaticity.
  
  
  METHODS
  In this two-part experiment, 129 undergraduates performed tasks involving spelling, arithmetic, memory, and visual search.
  
  
  RESULTS
  The fatigue cusp for the central memory task was supported with the quantity of work performed and performance on an episodic memory task acting as the control parameters. There was a strong linear effect, however. The load manipulations for the central task were competition with another participant for rewards, incentive conditions, and time pressure. Results supported the workload cusp in which trait anxiety and the incentive manipulation acted as the control parameters.
  
  
  CONCLUSIONS
  The cusps are generally better than linear models for analyzing workload and fatigue phenomena; practice effects can override fatigue. Future research should investigate multitasking and task sequencing issues, physical-cognitive task combinations, and a broader range of variables that contribute to flexibility with respect to load or compensate for fatigue.
  
  
  CONCLUSIONS
  The new experimental medium and analytic strategy can be generalized to virtually any real-world cognitively demanding tasks. The particular results are generalizable to tasks involving visual search.
authors.affiliation: Marquette University, P.O. Box 1881, Milwaukee, WI 53201-1881, USA. Stephen.guastello@marquette.edu
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Guastello
authors.forename: Henry
authors.initials: H
authors.lastname: Boeh
authors.forename: Michael
authors.initials: M
authors.lastname: Schimmels
authors.forename: Hillary
authors.initials: H
authors.lastname: Gorin
authors.forename: Samuel
authors.initials: S
authors.lastname: Huschen
authors.forename: Erin
authors.initials: E
authors.lastname: Davis
authors.forename: Natalie E
authors.initials: NE
authors.lastname: Peters
authors.forename: Megan
authors.initials: M
authors.lastname: Fabisch
authors.forename: Kirsten
authors.initials: K
authors.lastname: Poston
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D058443:Catastrophization / Q000523:psychology; D003071:Cognition / Q000502:physiology*; D005221:Fatigue / Q000523:psychology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008568:Memory / Q000502:physiology*; D015146:Midwestern United States; D013315:Stress, Psychological; D013647:Task Performance and Analysis; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology; D016526:Workload / Q000523:psychology*; D055815:Young Adult