Association of BDNF serum concentrations with central serotonergic activity: evidence from auditory signal processing

Disturbances of serotonergic neurotransmission in the brain have been implicated in the pathogenesis and maintenance of several psychiatric disorders. According to recent preclinical and clinical studies, the loudness dependence of auditory evoked potentials (LD) is related to the central serotonergic neurotransmission in humans. As the serotonergic phenotype has been reported to be associated with brain-derived neurotrophic factor (BDNF), we studied whether BDNF serum concentrations are related to LD in 109 healthy human volunteers (62 male, 47 female, age: 42.5+/-13.1 years). Pearson correlation showed a significant negative correlation between the BDNF serum concentrations and the LD measured at Fz (r=-0.259, p=0.007) and a trend for the Cz electrode (r=-0.185, p=0.055). Although this association needs to be replicated, the results are in line with the assumption that low serum BDNF levels reflect low central serotonergic neurotransmission as indicated by a strong LD.