title: Cognitive workload modulation through degraded visual stimuli: a single-trial EEG study.
abstract: OBJECTIVE
  Our experiments explored the effect of visual stimuli degradation on cognitive workload.
  
  
  METHODS
  We investigated the subjective assessment, event-related potentials (ERPs) as well as electroencephalogram (EEG) as measures of cognitive workload.
  
  
  RESULTS
  These experiments confirm that degradation of visual stimuli increases cognitive workload as assessed by subjective NASA task load index and confirmed by the observed P300 amplitude attenuation. Furthermore, the single-trial multi-level classification using features extracted from ERPs and EEG is found to be promising. Specifically, the adopted single-trial oscillatory EEG/ERP detection method achieved an average accuracy of 85% for discriminating 4 workload levels. Additionally, we found from the spatial patterns obtained from EEG signals that the frontal parts carry information that can be used for differentiating workload levels.
  
  
  CONCLUSIONS
  Our results show that visual stimuli can modulate cognitive workload, and the modulation can be measured by the single trial EEG/ERP detection method.
authors.affiliation: Singapore Institute for Neurotechnology, Centre for Life Sciences, National University of Singapore, Singapore. Faculty of Informatics & Electronics, Zhejiang Sci-Tech University, People's Republic of China.
authors.forename: K
authors.initials: K
authors.lastname: Yu
authors.forename: I
authors.initials: I
authors.lastname: Prasad
authors.forename: H
authors.initials: H
authors.lastname: Mir
authors.forename: N
authors.initials: N
authors.lastname: Thakor
authors.forename: H
authors.initials: H
authors.lastname: Al-Nashash
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D003463:Cues; D004569:Electroencephalography / Q000379:methods*; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D056344:Executive Function / Q000502:physiology; D006801:Humans; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*