1/n - here's how i am thinking about this -- "Despite this progress, it remains unclear whether dispositional negativity [N/NE] reflects heightened extended amygdala reactivity to threat. To date, the vast majority of studies have relied on emotional-face paradigms. While https://twitter.com/ajshackman/status/1314339700958781440

2/n - "emotional faces are among the most potent triggers of amygdala activity (Hur et al., 2019) and are widely used in a variety of on-going biobank projects , they do not elicit robust negative and, as such, do not represent a ‘trait-relevant’ challenge in the traditional

3/n - "sense. In emotional-face paradigms, ‘threat’ is operationalized as the difference in activity elicited by negative expressions (e.g., anger, fear) and either neutral expressions or simple control stimuli (e.g., geometric shapes, houses). While there is some evidence that

4/n-"dispositionally negative individuals show increased amygdala reactivity to negative expressions (Calder, Ewbank, & Passamonti, 2011; Fonzo et al., 2015; Fox & Kalin, 2014; Stein, Simmons, Feinstein, & Paulus, 2007), recent large-scale studies of middle-aged (Minnesota

5/n - "Twin Study: n = 548) and young adults (Duke Neurogenetics Study: n = 1,256) have consistently failed to detect credible relations (MacDuffie, Knodt, Radtke, Strauman, & Hariri, 2019; Silverman et al., 2019). On balance, this body of research suggests that the association

6/n - "between dispositional negativity and amygdala reactivity to emotional faces is negligible in magnitude, conditional on moderator variables*, or simply non-existent.

7/n - * so what about those moderators? Here are some ideas: The degree to which the faces are task-irrelevant or masked (Calder et al., 2011; Günther et al., 2020; Stout, Shackman, Pedersen, Miskovich, & Larson, 2017), the control condition (e.g., Neg-Pos v Neg-Shapes;

8/n-"Ball et al., 2012), the analytic approach (peak v. dispersion/persistence; Blackford, Avery, Cowan, Shelton, & Zald, 2011; Blackford, Avery, Shelton, & Zald, 2009), the degree of ambient stress (Everaerd, Klumpers, van Wingen, Tendolkar, & Fernández, 2015), the range of

9/n - "dispositional negativity (Ball et al., 2012; Greenberg et al., 2017), and/or the stimuli themselves (e.g. trial-unique color photos from multiple databases vs. repeated presentation of b/w photos from Ekman-Friesen). Of note, none of these moderators is expected to

10/n- "transform r=~tiny into r=~big..." On first principles, it is implausible that a hemodynamic proxy of mass amygdala cell responses to a static photo of an exaggerated facial expression would account for more than a small proportion of a trait that encompasses the propensity

11/n-"to experience more freq, intense, or persistent anger, sadness, fear/anx, particularly once you apprciate that much of the Trait-State action seems to happen in quiescent, emotionally neutral situations (Bolger & Schilling, 1991)...consistent with the items on widely used

12/n-"e.g. Do you ever feel miserable for now reason?" see also Perkins/Mobbs TiCS