Effects of Cognitive Load and State of Vigilance On Sympathetic

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KARİMİ N., Dolu N., Kiziltan E., Şirinoğlu T., Gundogan N.

Eastern Journal of Medicine, vol.28, no.3, pp.425-431, 2023 (Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 28 Issue: 3
  • Publication Date: 2023
  • Doi Number: 10.5505/ejm.2023.57070
  • Journal Name: Eastern Journal of Medicine
  • Journal Indexes: Scopus, Academic Search Premier, CAB Abstracts, CINAHL, EMBASE, Veterinary Science Database, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.425-431
  • Keywords: Cognitive load, reaction time, sympathetic skin response
  • Istanbul Medipol University Affiliated: Yes


The skin conductance response is one of the noninvasive peripheral markers of the activity of the sympathetic nervous system. Skin conductivity level monitorization during cognitive performance processes is used as a physiological indicator of task-related alertness and attention. This study is aimed to investigate the relationship between task-related sympathetic activity and reaction time in students 18–22 years of age. A total of 20 healthy male and female students were included in the study. Hand preference and color blindness tests were applied to the participants. Electrodermal activity recordings were recorded as tonic and phasic recordings during all tasks. Different colored 2-dimensional geometric objects were presented in fixed and random intervals through the computer system. The task performance of pressing the predefined button as soon as the stimulus appeared on the computer screen was investigated in relation to cognitive load and sympathetic stress response. Applying an increased amount of cognitive load increases sympathe tic stress response (p<0.001). An increase in reaction time was observed with the increasing amount of cognitive load (p<0.05). The similar task levels, on the other hand, cause statistically higher mean skin conductivity levels when a visual stimulus is presented at a fixed interval rather than a random stimulus interval. Beyond the expectations, our novel findings highlight the importance of the internal timestamp processes of individuals. Therefore, we may suggest that time estimation processes play a critical role in the generation of the sympathetic stress response when compared to the vigilance state caused by simply waiting for random stimuli.