Effects of serotonin depletion and dopamine depletion on bimodal divided attention. (15th March 2020)

• Record Type: Journal Article
• Authors: Königschulte, W.; Civai, C.; Hildebrand, P.; Gaber, T. J.; Fink, G. R.; Zepf, F. D.
• Is Part Of: World journal of biological psychiatry. Volume 21:Number 3(2020)
• Page Start: 183
• Page End: 194
• Publication Date: 2020-03-15
• Subjects: Acute tryptophan depletion -- phenylalanine tyrosine depletion -- serotonin -- dopamine -- attention; Biological psychiatry -- Periodicals; Biological Psychiatry -- Periodicals; 616.89
• DOI: 10.1080/15622975.2018.1532110
• Languages: English
• ISSNs: 1562-2975

Abstract

Abstract: Objectives: This study aimed to explore the effects of acute phenylalanine tyrosine depletion (APTD) and acute tryptophan depletion (ATD) on bimodal divided attention. A balanced amino acid mixture (BAL) served as control condition. Methods: Fifty-three healthy adults (final analyzed sample was N = 49, age: M = 23.8 years) were randomly assigned to APTD, ATD or BAL in a double-blind, between-subject approach. Divided attention was assessed after 4 h. Blood samples were taken before and 6 h after challenge intake. Results: Amino acid concentrations following challenge intake significantly decreased (all P ≤ 0.01). There was a significant difference in the mean reaction time (RT) towards auditory stimuli, but not towards visual stimuli between the groups. Post-hoc comparison of mean RTs (auditory stimuli) showed a significant difference between ATD (RT = 604.0 ms, SD = 56.9 ms) and APTD (RT = 556.4 ms, SD = 54.2 ms; P = 0.037), but no RT difference between ATD and BAL or APTD and BAL (RT = 573.6 ms, SD = 45.7 ms). Conclusions: The results indicate a possible dissociation between the effects of a diminished brain 5-HT and DA synthesis on the performance in a bimodal divided attention task. The difference was exclusively observed within the RT towards auditory signals.