Sympathetic Neural Control in Humans with Anxiety‐Related Disorders

Sympathetic neural reactivity to the Trier social stress test

“…Although mental stress paradigms are often accompanied by consistent increases in blood pressure and HR, variable MSNA responsiveness to mental stress is a persistent finding in the autonomic literature (Bigalke & Carter, 2021; Carter & Goldstein, 2015; Carter & Ray, 2009). Despite wide inter ‐individual variability, intra ‐individual responses to mental stress and arousal appear to be reproducible (Donadio et al., 2002; Fonkoue & Carter, 2015).…”

“…Despite wide inter ‐individual variability, intra ‐individual responses to mental stress and arousal appear to be reproducible (Donadio et al., 2002; Fonkoue & Carter, 2015). While the influence of factors such as baroreflex function (Anderson et al., 1991; Durocher et al., 2009, 2011), rate of blood pressure changes (El Sayed et al., 2016, 2018), psychological factors (Bigalke & Carter, 2021) and perceived stress (Callister et al., 1992; Carter et al., 2008) have been explored, a consensus has not yet been reached regarding the physiological underpinning of variations in stress reactivity. Many commonly utilized stress tests are performed with the addition of multiple confounds such as irregular breathing patterns and depth, active talking, muscle movements and other confounds that may impact MSNA recordings and subsequent data interpretation.…”

“…Recent studies have begun to assess the influence of anticipatory stress on sympathetic control of cardiovascular function (Brown et al., 2013; Holwerda et al., 2018; Manabe et al., 2020). Specifically, anticipatory stress may be able to distinguish the effects of trait psychological characteristics on sympathetic reactivity to stress (Bigalke & Carter, 2021; Holwerda et al., 2018). Furthermore, anticipatory stress may offer a more ecologically valid form of mental stress whereby confounds such as irregular breathing and muscle movement are eliminated, allowing a more reliable interpretation of the resultant sympathetic response.…”

“…Abnormal sympathetic nervous system activity has been implicated in the development (Hering et al., 2016; Matsukawa et al., 1991; Spraul et al., 1993) and maintenance of both cardiovascular and metabolic disorders (Grassi et al., 2018, 2019; Quarti Trevano et al., 2020), indicating a role for sympathetic alterations in the relationship between impaired stress responsiveness and future deleterious health outcomes. While a great deal of effort has been put forth to quantify the sympathetic response to mental stress using direct recordings of muscle sympathetic nerve activity (MSNA), variable responses remain pervasive (Bigalke & Carter, 2021; Carter & Goldstein, 2015; Carter & Ray, 2009), with some studies observing increased (Anderson et al., 1987, 1991; Callister et al., 1992; Carter & Lawrence, 2007; Carter & Ray, 2009; Matsukawa et al., 1995), decreased (Carter & Ray, 2009; Halliwill et al., 1997) or unchanged sympathetic activity (Carter et al., 2008; Incognito et al., 2019; Kuipers et al., 2008; Wasmund et al., 2002). Despite inter‐individual variability, responses within individuals are reproducible (Donadio et al., 2002; Fonkoue & Carter, 2015).…”

“…Despite inter‐individual variability, responses within individuals are reproducible (Donadio et al., 2002; Fonkoue & Carter, 2015). While the responsible mechanism for this assorted between‐subject reactivity has been an active area of investigation (for reviews see: Bigalke & Carter, 2021; Carter & Goldstein, 2015), a clear mediator for these spurious findings has not been determined.…”