BDNF CONCENTRATION IS RELATED TO CENTRAL 5-HT ACTIVITY
It is known that the loudness dependence of auditory evoked potentials (LD) is related to the central 5-HT transmission in humans. As the serotonergic phenotype has been associated to serum BDNF levels, Lang, Hellweg and Gallinat studied whether BDNF serum concentrations are related to LD in 109 healthy human volunteers (Association of the BDNF Serum Concentrations with Central Serotonergic Activity: Evidence from Auditory Signal Processing. Neuropsychopharmacology 30, 1148-1153, 2005).
The results indicate a reasonably correlation. Low serum levels of BDNF reflect a central low activity of serotonergic system.
Since disturbances of serotonergic system have been implicated in several psychiatric disorders these results could have some relevance in psychiatry.