title: The loudness dependence auditory evoked potential is insensitive to acute changes in serotonergic and noradrenergic neurotransmission.
abstract: BACKGROUND
  The loudness dependence of the auditory evoked potential (LDAEP) has been proposed as an electrophysiological marker for assessing serotonergic function in vivo in humans, although accumulating evidence suggests that it is insensitive to acute changes in serotonergic neurotransmission. Very little is known about the sensitivity of the LDAEP to other neurotransmitter systems including the noradrenergic system. The current study examined the effects of noradrenergic modulation as well as serotonergic modulation on the LDAEP.
  
  
  METHODS
  The study utilised a double-blind placebo-controlled design in which the LDAEP in 17 healthy males and females was tested following acute administration of each of citalopram (20 mg), reboxetine (4 mg) and placebo.
  
  
  RESULTS
  Neither citalopram nor reboxetine modulated the LDAEP relative to placebo treatment (p > 0.05).
  
  
  CONCLUSIONS
  These findings suggest that the LDAEP is insensitive to acute changes in serotonergic or noradrenergic neurotransmission and thus is a poor pharmacodynamic marker of these systems.
authors.affiliation: School of Psychology and Psychiatry, Monash University, Melbourne, VIC, Australia.
authors.forename: Jessica
authors.initials: J
authors.lastname: Oliva
authors.forename: Sumie
authors.initials: S
authors.lastname: Leung
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Croft
authors.forename: Barry V
authors.initials: BV
authors.lastname: O'Neill
authors.forename: Joanne
authors.initials: J
authors.lastname: O'Kane
authors.forename: Julie
authors.initials: J
authors.lastname: Stout
authors.forename: K Luan
authors.initials: KL
authors.lastname: Phan
authors.forename: Pradeep J
authors.initials: PJ
authors.lastname: Nathan
mesh_terms: D000293:Adolescent; D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology; D000328:Adult; D015283:Citalopram / Q000494:pharmacology*; D004311:Double-Blind Method; D055724:Electrophysiological Phenomena / Q000187:drug effects; D005072:Evoked Potentials, Auditory / Q000187:drug effects*; D005260:Female; D006801:Humans; D008144:Loudness Perception / Q000187:drug effects; D008297:Male; D009025:Morpholines / Q000494:pharmacology*; D009638:Norepinephrine / Q000378:metabolism; D000077593:Reboxetine; D012701:Serotonin / Q000378:metabolism; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology; D055815:Young Adult
chemical_list: D018759:Adrenergic Uptake Inhibitors; D015283:Citalopram; D009025:Morpholines; D009638:Norepinephrine; D000077593:Reboxetine; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors