Experimentally-Induced Inflammation Predicts Present Focus

Why inflammation and the activities of the immune system matter for social and personality psychology (and not only for those who study health)

“…Lastly, research indicates that the activities of the immune system may play a powerful-if not yet well understood -role in the motivation and preference for appetitive stimuli, such as money and food (Dooley et al, 2018;Draper et al, 2018;Eisenberger, Berkman, et al, 2010;Gassen, Prokosch et al, 2019;Gassen, Makhanova et al, 2019;Lasselin et al, 2017). For example, fMRI research in humans finds that inflammation predicts lesser ventral striatum activity in response to monetary reward cues (Eisenberger, Berkman, et al, 2010), as well as decreased functional connectivity in the brain's neural reward circuitry (Felger et al, 2016).…”

“…There are cytokine receptors present in virtually all neural cell types (Bartfai & Schultzberg, 1993;Conti et al, 2008;Kronfol & Remick, 2000;Vitkovic et al, 2000), and much research finds that modifying the action of cytokines leads to changes in the central nervous system. For example, research finds that such actions have implications for sensory function (Chen et al, 2017;Miller, Jung, et al, 2009), sleep (Fang, Wang, & Krueger, 1998;Jewett & Krueger, 2012), learning (Gonzalez, Schiöth, Lasaga, & Scimonelli, 2009;Goshen et al, 2007;Huang & Sheng, 2010;Jones, Lebonville, Barrus, & Lysle, 2015;Takemiya, Fumizawa, Yamagata, Iwakura, & Kawakami, 2017), the stress response (Goshen & Yirmiya, 2009), temporal focus (Gassen, Makhanova, et al, 2019;Gassen, Prokosch, et al, 2019), and even social behavior (Hennessy et al, 2014;Lisboa et al, 2018;Moon et al, 2015;Yim et al, 2017). The impact of cytokines on the activities of the nervous system is therefore unlikely to be limited to the impact they have on organisms' behaviors when they are sick.…”

“…Although the proposal that the immune system may be an important player in guiding the activities of a healthy nervous system is relatively new, a growing body of research has begun to find hints of immune system involvement in a variety of outcomes that are observed both in sickness and in health. For example, research suggests that the activities of the immune system may have a hand in calibrating psychological outcomes as diverse as personality (Segerstrom, 2000;Vedhara et al, 2015), pathogen avoidance motivation (Fessler, Eng, & Navarrete, 2005;Fleischman & Fessler, 2011;Gangestad & Grebe, 2014;Gassen et al, 2018), disgust sensitivity (Bradshaw, Gassen, Prokosch, Boem, & Hill, under review), the desire for immediate versus delayed rewards (Gassen et al, 2018;Gassen, Makhanova, et al, 2019;Gassen, Prokosch, et al, 2019), learning (Ziv et al, 2006;Derecki et al, 2010), and mood (Raison & Miller, 2011).…”

“…We have proposed that the activities of the immune system may play an important role in what people think, feel, and do, even outside the context of illness (e.g., Gassen et al, 2018;Gassen, Makhanova, et al, 2019;Gassen, Prokosch, et al, 2019;Kipnis, 2018;Maier & Watkins, 1998;Vitkovic et al, 2000). Although the immune system does not typically weigh heavily in the minds of researchers in personality and social psychology, incorporating mechanistic insights from PNI into the study of person-situation interactions has much to offer researchers in these areas.…”

“…For example, disparate lines of research indicate that growing up in conditions of low socioeconomic status (SES) promotes (a) the development of an exaggerated inflammatory response to immunological stimulation (Miller, Chen, et al, 2009;Miller & Chen, 2007) and (b) the tendency to act impulsively in response to stress (Griskevicius et al, 2013;Griskevicius, Tybur, Delton, & Robertson, 2011). Given recent empirical work linking heightened inflammatory activity to decision making characterized by impulsivity (Gassen, Makhanova, et al, 2019;Gassen, Prokosch, et al, 2019), it is possible that signaling by the immune system may play a mechanistic role linking one's early life environments with how they respond to stressors in adulthood. Incorporating insights from psychoneuroimmunology into research on individual differences in stress reactivity therefore has the potential of bridging these previously disconnected bodies of research, raising the possibility that differences in the magnitude of the inflammatory response may play an important role in differential susceptibility to other stress-induced behavioral changes that are often disproportionately represented in the poor (e.g., Griskevicius et al, 2011;Griskevicius et al, 2013).…”