Effects of Acute Tryptophan Depletion on the Loudness Intensity Dependence in a Healthy Female Population

Objectives: Animal and human studies suggest an inverse influence of the serotonergic system on the intensity dependence of early event-related potentials for the primary acoustic cortex, namely the N1/P2 component. Meanwhile, procedures by tryptophan depletion tests (TDT) represent an established human challenge tool for a temporary reduction of tryptophan levels and central nervous serotonin. Methods: 16 healthy females volunteered twice to ingest a highly concentrated amino acid mixture with (+) TRP or without (-) TRP in a double-blind cross-over study design: In relation to the individual basic value plasma…