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Cannabis affects people differently: inter-subject variation in the psychotogenic effects of Δ9-tetrahydrocannabinol: a functional magnetic resonance imaging study with healthy volunteers

Published online by Cambridge University Press:  01 October 2012

Z. Atakan ,
S. Bhattacharyya ,
P. Allen ,
R. Martín-Santos ,
J. A. Crippa ,
S. J. Borgwardt ,
P. Fusar-Poli ,
M. Seal ,
H. Sallis  and
D. Stahl
...Show all authors
Z. Atakan*
Affiliation:
Section of Neuroimaging, Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK
S. Bhattacharyya
Affiliation:
Section of Neuroimaging, Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK
P. Allen
Affiliation:
Section of Neuroimaging, Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK
R. Martín-Santos
Affiliation:
Institut Municipal Investigació Mèdica IMIM Hospital del Mar, Barcelona, Spain
J. A. Crippa
Affiliation:
Departamento de Neuropsiquiatria e Psicologia Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil
S. J. Borgwardt
Affiliation:
Psychiatric Outpatient Department, University Hospital Basel, Basel, Switzerland
P. Fusar-Poli
Affiliation:
Section of Neuroimaging, Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK
M. Seal
Affiliation:
Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, Australia
H. Sallis
Affiliation:
Department of Biostatistics, Institute of Psychiatry, King's College London, London, UK
D. Stahl
Affiliation:
Department of Biostatistics, Institute of Psychiatry, King's College London, London, UK
A. W. Zuardi
Affiliation:
Departamento de Neuropsiquiatria e Psicologia Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil
K. Rubia
Affiliation:
Section of Developmental Neuropsychology and Neuroimaging, Institute of Psychiatry, King's College London, London, UK
P. McGuire
Affiliation:
Section of Neuroimaging, Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK
*
*Address for correspondence: Z. Atakan, M.D., Department of Psychosis Studies, PO67, Section of Neuroimaging, Institute of Psychiatry, King's College London, DeCrespigny Park, London, SE5 8AF, UK. (Email: Zerrin.Atakan@kcl.ac.uk)
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Abstract

Background

Cannabis can induce transient psychotic symptoms, but not all users experience these adverse effects. We compared the neural response to Δ9-tetrahydrocannabinol (THC) in healthy volunteers in whom the drug did or did not induce acute psychotic symptoms.

Method

In a double-blind, placebo-controlled, pseudorandomized design, 21 healthy men with minimal experience of cannabis were given either 10 mg THC or placebo, orally. Behavioural and functional magnetic resonance imaging measures were then recorded whilst they performed a go/no-go task.

Results

The sample was subdivided on the basis of the Positive and Negative Syndrome Scale positive score following administration of THC into transiently psychotic (TP; n = 11) and non-psychotic (NP; n = 10) groups. During the THC condition, TP subjects made more frequent inhibition errors than the NP group and showed differential activation relative to the NP group in the left parahippocampal gyrus, the left and right middle temporal gyri and in the right cerebellum. In these regions, THC had opposite effects on activation relative to placebo in the two groups. The TP group also showed less activation than the NP group in the right middle temporal gyrus and cerebellum, independent of the effects of THC.

Conclusions

In this first demonstration of inter-subject variability in sensitivity to the psychotogenic effects of THC, we found that the presence of acute psychotic symptoms was associated with a differential effect of THC on activation in the ventral and medial temporal cortex and cerebellum, suggesting that these regions mediate the effects of the drug on psychotic symptoms.

Keywords

CerebellumfMRImiddle temporal gyriparahippocampusresponse inhibitionTHC
Type
Original Articles
Information
Psychological Medicine , Volume 43 , Issue 6 , June 2013 , pp. 1255 - 1267
Copyright
Copyright © Cambridge University Press 2012 

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