PMID- 17299516
OWN - NLM
STAT- MEDLINE
DCOM- 20071129
LR  - 20191210
IS  - 0893-133X (Print)
IS  - 0893-133X (Linking)
VI  - 32
IP  - 9
DP  - 2007 Sep
TI  - The effects of the preferential 5-HT2A agonist psilocybin on prepulse inhibition 
      of startle in healthy human volunteers depend on interstimulus interval.
PG  - 1876-87
AB  - Schizophrenia patients exhibit impairments in prepulse inhibition (PPI) of the 
      startle response. Hallucinogenic 5-HT(2A) receptor agonists are used for animal 
      models of schizophrenia because they mimic some symptoms of schizophrenia in 
      humans and induce PPI deficits in animals. Nevertheless, one report indicates 
      that the 5-HT(2A) receptor agonist psilocybin increases PPI in healthy humans. 
      Hence, we investigated these inconsistent results by assessing the dose-dependent 
      effects of psilocybin on PPI in healthy humans. Sixteen subjects each received 
      placebo or 115, 215, and 315 microg/kg of psilocybin at 4-week intervals in a 
      randomized and counterbalanced order. PPI at 30-, 60-, 120-, 240-, and 2000-ms 
      interstimulus intervals (ISIs) was measured 90 and 165 min after drug intake, 
      coinciding with the peak and post-peak effects of psilocybin. The effects of 
      psilocybin on psychopathological core dimensions and sustained attention were 
      assessed by the Altered States of Consciousness Rating Scale (5D-ASC) and the 
      Frankfurt Attention Inventory (FAIR). Psilocybin dose-dependently reduced PPI at 
      short (30 ms), had no effect at medium (60 ms), and increased PPI at long 
      (120-2000 ms) ISIs, without affecting startle reactivity or habituation. 
      Psilocybin dose-dependently impaired sustained attention and increased all 5D-ASC 
      scores with exception of Auditory Alterations. Moreover, psilocybin-induced 
      impairments in sustained attention performance were positively correlated with 
      reduced PPI at the 30 ms ISI and not with the concomitant increases in PPI 
      observed at long ISIs. These results confirm the psilocybin-induced increase in 
      PPI at long ISIs and reveal that psilocybin also produces a decrease in PPI at 
      short ISIs that is correlated with impaired attention and consistent with 
      deficient PPI in schizophrenia.
FAU - Vollenweider, Franz X
AU  - Vollenweider FX
AD  - University Hospital of Psychiatry, Neuropsychopharmacology and Brain Imaging & 
      Heffter Research Center, Lenggstrasse 31, CH-8032 Zurich, Switzerland. 
      vollen@bli.unizh.ch
FAU - Csomor, Philipp A
AU  - Csomor PA
FAU - Knappe, Bernhard
AU  - Knappe B
FAU - Geyer, Mark A
AU  - Geyer MA
FAU - Quednow, Boris B
AU  - Quednow BB
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20070214
PL  - England
TA  - Neuropsychopharmacology
JT  - Neuropsychopharmacology : official publication of the American College of 
      Neuropsychopharmacology
JID - 8904907
RN  - 0 (Serotonin 5-HT2 Receptor Agonists)
RN  - 2RV7212BP0 (Psilocybin)
SB  - IM
MH  - Acoustic Stimulation/methods
MH  - Adult
MH  - Analysis of Variance
MH  - Attention/drug effects
MH  - Dose-Response Relationship, Drug
MH  - Double-Blind Method
MH  - Female
MH  - Humans
MH  - *Inhibition, Psychological
MH  - Male
MH  - Psilocybin/*pharmacology
MH  - Psychological Tests
MH  - Reflex, Startle/*drug effects/physiology
MH  - *Serotonin 5-HT2 Receptor Agonists
MH  - Time Factors
EDAT- 2007/02/15 09:00
MHDA- 2007/12/06 09:00
CRDT- 2007/02/15 09:00
PHST- 2007/02/15 09:00 [pubmed]
PHST- 2007/12/06 09:00 [medline]
PHST- 2007/02/15 09:00 [entrez]
AID - 1301324 [pii]
AID - 10.1038/sj.npp.1301324 [doi]
PST - ppublish
SO  - Neuropsychopharmacology. 2007 Sep;32(9):1876-87. doi: 10.1038/sj.npp.1301324. 
      Epub 2007 Feb 14.