Religion and Spirituality in Psychiatry

60 Nader Perroudby his behavior, elicit a spiritual environmentbecause of his or her particular genotype. This inturn will enable the individual to cope better.5.2.3. The Active rGEActive rGE refers to the association between anindividual’s genetically influenced traits and theenvironmental niches selected by this individual.For example, individuals who are highly spiritualmay seek out religious community to expresstheir spirituality. Here the individual, becauseof his genetic background, will actively seek anenvironment that will enhance the expression ofhis genes. Contrary to the latter, with the evocativerGE, the individual will be “discovered” bythose around him.All these examples illustrate how, in some cases,a genetic effect can be detected or have a differentimpact on a trait only when an environmentalvariable is taken into account. The major questionin studies dealing with spirituality is this: Whichenvironmental factor should one study in relationto this trait? Personality seems to be influencedby parenting style. The intensity of parental careor the intrusiveness of parents should probablybe important environmental candidates. Otherenvironmental factors are presupposed. It hasbeen found that religiousness has a large sharedenvironmental component (that is, environmentalfactors shared by close relatives), especially inchildhood and adolescence. For example, heritabilityfactors for religiousness may have less influencein childhood than in adulthood, showingthat age is an environmental moderator of theheritability and should be taken into account.(35 )As mentioned above, hormonal levels (partiallyunder genetic control also), ethnicity, and drugsare also putative environmental factors.The demonstration that early environmentalfactors could considerably strengthen or even highlightassociations between genes and personalityis a promising new area of research in complexbehavior. The publication by Caspi and his coworkers(66 ) showed what was widely hypothesizedbut rarely demonstrated. This important workstated that both nature and nurture contribute tothe shaping of behavior. Many studies have sincetried to find such interaction in psychiatry. Forexample, it has been shown that individuals sexuallyabused in their childhood displayed higherrisk of making a violent suicide attempt only ifthey were carrying a particular genotype.(69 ) Suchstudies should be promising in the understandingof spirituality. However, human personality andspirituality are complex traits and require a moreencompassing view to understand their geneticand molecular architecture.5.3. Religious Activity asan Environmental Factor?Contrary to spirituality, religious activities, whichare supposedly less heritable and so less underthe influence of genes, could be seen as environmentalfactors. Given the impact of meditationon 5-HT, dopamine levels, and the functioningof the brain, it would be surprising if religiousactivities did not have an impact on the geneexpression. Within this perspective, Timberlakeet al.(70 ) investigated the moderating effects ofthree styles of religiosity (religious affiliation,organizational religious activity, and self-ratedreligiousness) on the genetic and environmentaldeterminants of smoking initiation. They foundthat self-rated religiousness moderated geneticinfluences on the likelihood for smoking. Thiskind of study could also have a huge impact onpsychiatric disorders. If we consider religiouspractice as an environmental factor, it would beinteresting to know, based on an individual’s genotype,which individual is susceptible to respondfavorably and which is not.6. CONCLUSIONThe results from the present review might suggestthat a high degree of spirituality is linked to5-HT and dopaminergic systems. In the initialCloninger hypothesis, it was proposed that differentpersonality traits were influenced by genesrelated to 5-HT, and dopaminergic and noradrenalin-relatedgenes. The above studies of 5-HT anddopaminergic genes suggest higher levels of activityin both systems, not only in individuals with a