Systemic inflammation is associated with differential neural reactivity and connectivity to affective images

Abstract

<jats:title>Abstract</jats:title> <jats:p>Systemic inflammation is increasingly appreciated as a predictor of health and well-being. Further, inflammation has been shown to influence and be influenced by affective experiences. Although prior work has substantiated associations between inflammatory and affective processes, fewer studies have investigated the neurobiological correlates that underlie links between systemic, low-grade inflammation and affective reactivity. Thus, the current study examined whether markers of systemic inflammation (i.e. interleukin-6, C-reactive protein) are associated with differential patterns of neural activation and connectivity in corticolimbic regions in response to affective images. We investigated this question in a sample of 66 adults (44 women, M age = 54.98 years, range = 35–76) from the Midlife in the United States study. Higher levels of inflammation were associated with lower activity in limbic regions (i.e. amygdala, hippocampus, anterior insula, temporal pole) when viewing positive (vs neutral) images. Higher levels of inflammation were also associated with greater connectivity between the hippocampus and the medial prefrontal cortex in response to positive images. Inflammatory markers were not associated with significant differences in activation or connectivity to negative images. These findings highlight the utility of health neuroscience approaches in demonstrating that physiological processes such as inflammation are related to how our brains respond to affective information.</jats:p>

Aging as a Context for the Role of Inflammation in Depressive Symptoms

“…Finally, it is important to note that we did not observe a link between inflammation and depressed affect in our sample, which is consistent with prior literature ( 42 , 77 , 91 , 92 ) but often neglected in research on the role of inflammation in depressive symptoms. To our knowledge, the only studies which have found a significant link between inflammation and depressed affect have involved presenting the immune system with a short-term, strong inflammatory challenge which produces brief, high levels of inflammation in some individuals ( 22 , 27 , 30 ).…”

“…The present findings provide promising preliminary evidence that aging is an important context to consider in the role of inflammation in anhedonia, the neural mechanisms of which warrant further investigation. Indeed, in a study conducted with another subset of MIDUS participants, higher inflammation was associated with lower limbic reactivity to positive affective images and greater connectivity between the limbic system and prefrontal cortex ( 77 ). Inflammation affects reward learning, sensitivity, and motivation through frontostriatal circuit function in many ways, including interfering with dopamine synthesis ( 78 ).…”

Health neuroscience 2.0: integration with social, cognitive and affective neuroscience

“…machine learning to identify multivariate patterns of neural activity) to predict a host of the most pressing health issues facing society today: cardiovascular disease ( Gianaros et al , 2020 ), obesity ( Stice et al , 2019 ; Cosme et al , 2020 ; Donofry et al , 2020 ; Verstynen et al , 2020 ) and physical pain ( Reddan et al , 2020 ). Similar approaches help us understand links between brain patterns of activity to emotional content and systemic inflammation, a key biological mediator linking psychological experience and health ( Alvarez et al , 2020 ), or to health messages and population-level sharing of the information ( Dore et al ., in press ). And supplementing the use of task-based imaging, there is also promise in examining links between resting state brain connectivity and health-relevant outcomes ( Inagaki and Meyer, 2019 ; Mehta et al , 2019 ).…”

“…As a specific example from the current special issue on health neuroscience, decades of research from human neuroimaging uses standardized sets of emotional images in order to elicit activity in affect-related brain regions (medial prefrontal cortex, anterior cingulate cortex, anterior insula, amygdala, etc.). More than half of the empirical studies in the current special issue use some version of ‘emotional’ static images ( Inagaki and Meyer, 2019 ; Stice et al , 2019 ; Alvarez et al , 2020 ; Cosme et al , 2020 ; Gianaros et al , 2020 ; Leschak et al , 2020 ). Standardized images have undoubtedly produced valuable information.…”

“…As both healthy life expectancy and life expectancy increase worldwide ( World Health Organization, 2020 ), there is also an urgent need to conduct research at later stages of life. Existing longitudinal brain datasets are publicly available for exploration (examples from the current special issue include MIDUS ( Alvarez et al, 2020 ) and AHAB-II ( Gianaros et al , 2020 ; Verstynen et al , 2020 )), but an additional way that social, cognitive and affective neuroscientists can contribute to the lifespan perspective is by extending their paradigms to new age groups (especially midlife and later life).…”