Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
2008-12-4
pubmed:abstractText
Placebo may yield beneficial effects that are indistinguishable from those of active medication, but the factors underlying proneness to respond to placebo are widely unknown. Here, we used functional neuroimaging to examine neural correlates of anxiety reduction resulting from sustained placebo treatment under randomized double-blind conditions, in patients with social anxiety disorder. Brain activity was assessed during a stressful public speaking task by means of positron emission tomography before and after an 8 week treatment period. Patients were genotyped with respect to the serotonin transporter-linked polymorphic region (5-HTTLPR) and the G-703T polymorphism in the tryptophan hydroxylase-2 (TPH2) gene promoter. Results showed that placebo response was accompanied by reduced stress-related activity in the amygdala, a brain region crucial for emotional processing. However, attenuated amygdala activity was demonstrable only in subjects who were homozygous for the long allele of the 5-HTTLPR or the G variant of the TPH2 G-703T polymorphism, and not in carriers of short or T alleles. Moreover, the TPH2 polymorphism was a significant predictor of clinical placebo response, homozygosity for the G allele being associated with greater improvement in anxiety symptoms. Path analysis supported that the genetic effect on symptomatic improvement with placebo is mediated by its effect on amygdala activity. Hence, our study shows, for the first time, evidence of a link between genetically controlled serotonergic modulation of amygdala activity and placebo-induced anxiety relief.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1529-2401
pubmed:author
pubmed:issnType
Electronic
pubmed:day
3
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13066-74
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:19052197-Adult, pubmed-meshheading:19052197-Amygdala, pubmed-meshheading:19052197-Anxiety Disorders, pubmed-meshheading:19052197-DNA Mutational Analysis, pubmed-meshheading:19052197-Double-Blind Method, pubmed-meshheading:19052197-Female, pubmed-meshheading:19052197-Gene Frequency, pubmed-meshheading:19052197-Genetic Predisposition to Disease, pubmed-meshheading:19052197-Genetic Testing, pubmed-meshheading:19052197-Genotype, pubmed-meshheading:19052197-Humans, pubmed-meshheading:19052197-Male, pubmed-meshheading:19052197-Middle Aged, pubmed-meshheading:19052197-Neuropsychological Tests, pubmed-meshheading:19052197-Placebo Effect, pubmed-meshheading:19052197-Polymorphism, Genetic, pubmed-meshheading:19052197-Positron-Emission Tomography, pubmed-meshheading:19052197-Serotonin, pubmed-meshheading:19052197-Serotonin Plasma Membrane Transport Proteins, pubmed-meshheading:19052197-Stress, Psychological, pubmed-meshheading:19052197-Tryptophan Hydroxylase, pubmed-meshheading:19052197-Young Adult
pubmed:year
2008
pubmed:articleTitle
A link between serotonin-related gene polymorphisms, amygdala activity, and placebo-induced relief from social anxiety.
pubmed:affiliation
Department of Psychology, Uppsala University, Uppsala, Sweden. tomas.furmark@psyk.uu.se
pubmed:publicationType
Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't