This study sought to measure the influence of Pentecostal worship on baseline autonomic and SNS activity through measures of stress physiology. It was hypothesized that worship would stimulate HPA and SNS arousal on Sunday relative to Monday. Cortisol measures indicate that lower levels occur across the Monday diurnal cycle, but this is more attributable to general Christian religiosity, social status, sleep quality, church attended, and social support than specifically to Pentecostal behavior. However, the covariate selection process suggested that Pentecostal behavior is important and merits further examination. Alternatively, sAA yielded a diurnal pattern higher on Monday rather than lower, and this was attributable in the model only to Pentecostal behavior and age. This contrast suggests that further research is required to better understand the influence of religious behavior on the physiology of human stress and adaptation, yet it supports recent data indicating nonoverlapping activity in the HPA axis and SNS.
This study included cortisol as a standard noninvasive field method for assessing HPA axis over an extended period. Additionally, we used α-amylase as a proxy of SNS activity because multiple methods are suggested to better assess stress physiology (Lovallo and Thomas, 2000
). This biomarker combination has been used in a handful of recent studies (e.g., Gordis et al., 2006
; Granger et al., 2006
; Kivlighan and Granger, 2006
; Strahler et al., 2010
; Wolf et al., 2008
) but not previously in biocultural research. On the basis of the associations of salivary cortisol and sAA with the HPA axis and SNS, respectively, it was expected that, although both would display typical diurnal patterns, elevations would indicate the temporal proximity of stressful experiences. Elevations in sAA would indicate more recent stressful experiences because of the quicker reactivity of the SNS system and elevations in cortisol indicative of earlier experiences because of the slower reactivity of the HPA axis (Chrousos and Gold, 1992
). This is the pattern observed in laboratory studies using the Trier Social Stress test (Gordis et al., 2006
; Stroud et al., 2006
). This study took place in a naturalistic setting with no induced stress by which to evaluate this inference. However, the elevation of sAA at 10 p.m. on both Sunday and Monday and 6 p.m. on Sunday may be indicative of known potential stressors experienced immediately before the sample was taken. Sunday 6 p.m. is approximately when the evening evangelical service begins at one of the churches, whereas 10 p.m. may be relatively late for many participants and receiving a call or text to take a saliva sample possibly an aggravation.
There is a debate as to the specificity of the HPA axis and SNS as stress systems, with essentially three different positions being taken (Brandtstädter et al., 1991
). One is that the HPA axis is responsive to perceived “threats,” whereas the SNS could be better termed an “arousal” system (Frankenhaeuser, 1979
; Lundberg and Frankenhaeuser, 1980
). Another position is that the adrenal cortex (HPA) and adrenal medulla (SNS) mediate different behavioral modes, with the former associated with “threats to control,” whereas the latter relates to withdrawal behaviors or “loss of control” (Henry, 1980
; Henry and Stephens, 1977
). The third argument holds that HPA axis activity is related to readjustment to situations beyond the normal or expected (Gunnar, 1986
). These positions are not necessarily mutually exclusive and suggest several interpretations of the current data. The greater sAA (SNS) elevation related to Pentecostal behavior on Sunday can be associated with the arousal of Pentecostal worship (i.e., speaking in tongues, gospel singing, movement), whereas the higher Monday levels may be attributable to more active lives of those relatively more involved in the church. In other words, someone who is more active in the church community might generally lead a more active lifestyle. One recent study found religious older women but not older men or young people likely to exercise and enjoy active lives (Gillum, 2006
), whereas another found religious people, in general, more likely to lead a healthy active lifestyle but that this association is less pronounced with age (Hill et al., 2007
). This might entail a concomitant elevation in SNS activity. The third position is consistent with the study hypothesis and data in suggesting that cortisol should not be elevated in experienced Pentecostals because ritual religious behavior is repetitious by nature and normalizes behavior and creates predictability.
To better understand these relationships, this study looked at the associations of stress biomarkers and several factors. We found several significant associations with cortisol, whereas sAA was associated only with glossolalia (i.e., Pentecostalism) and age. Given the variations in sAA levels, this suggests that sAA may be sensitive to more factors rather than fewer. Salivary α-amylase levels have been found to increase to a significantly greater degree in response to a stressor than did cortisol in 40% of participants, which Granger et al. (2007)
have interpreted as due to a more sensitive threshold of reactivity in the SNS than the HPA axis, such that sAA is produced more readily to milder arousal states than are required for cortisol production (compare Het et al., 2009
). Lacks of correlation between salivary cortisol and sAA at baseline, in response to stress, or during recovery have similarly been taken to mean that these biomarkers are indexing different stress–response systems (Chatterton et al., 1996
; Granger et al., 2007
), an interpretation lent further support by a lack of correlation across the lifecycle (Strahler et al., 2010
). This is consistent with previous studies of cortisol and catecholamines (e.g., Lundberg, 1983
). As such, they may be sensitive to different types of arousal. In a study of a collegiate crew team, Kivlighan and Granger (2006)
found higher sAA to be positively associated with performance and team bonding. In this dataset, higher levels were observed among those more invested in Pentecostal models of behavior, as indicated by glossolalia behavior (Lynn et al., submitted for publication). These same individuals are also more likely to be active in services and as officers in the church, behaviors that may be comparable with performance and bonding.