Intrauterine Device Use: A New Frontier for Behavioral Neuroendocrinology

Intrauterine devices (IUDs) are the most-used reversible contraceptive method for women in the world, but little is known about their potential modulation of brain function, cognition, and behavior. This is disconcerting because research on other hormonal contraceptives, especially oral contraceptives (OCs), increasingly shows that exogenous sex hormones have behavioral neuroendocrine consequences, especially for gendered cognition, including spatial skills. Effects are small and nuanced, however, partially reflecting heterogeneity. The goal of this paper is to introduce IUD use as a new frontier for basic and applied research, and to offer key considerations for studying it, emphasizing the importance of multimodal investigations and person-specific analyses. The feasibility and utility of studying IUD users is illustrated by: scanning women who completed a functional magnetic resonance imaging mental rotations task; taking an individualized approach to mapping functional connectivity during the task using network analyses containing connections common across participants and unique to individual women, focusing on brain regions in putative mental rotations and default mode networks; and linking metrics of brain connectivity from the individualized networks to both mental rotations task performance and circulating hormone levels. IUD users provide a promising natural experiment for the interplay between exogenous and endogenous sex hormones, and they are likely qualitatively different from OC users with whom they are often grouped in hormonal contraceptive research. This paper underscores how future research on IUD users can advance basic neuroendocrinological knowledge and women’s health

Test-Retest Reliability in Functional Magnetic Resonance Imaging: Impact of Analytical Decisions on Individual and Group Estimates in the Monetary Incentive Delay Task.

Stage 1 Registered Report: Empirical studies reporting low test-retest reliability of individual neural estimates in functional magnetic resonance imaging (fMRI) data have resurrected interest among cognitive neuroscientists in methods that may improve reliability in fMRI. Over the last decade, several individual studies have reported that modeling decisions, such as smoothing, motion correction and contrast selection, may improve estimates of test-retest reliability of neural estimates. However, it remains an empirical question whether certain analytic decisions consistently improve individual and group level reliability estimates in an fMRI task across multiple large, independent samples. This study uses three independent samples (approximate Ns: 65, 150 & 2,000) that collected the same task across two runs and two sessions to evaluate the effects of analytic decisions on the individual (continuous) and group (binary) reliability estimates of neural activity in task fMRI. The analytic decisions in this study vary across four categories: smoothing kernel (five options), motion correction (six options), task parameterizing (three options) and task contrasts (four options), totaling 360 different modeling permutations. Continuous and binary reliability estimates of neural activity are calculated within and between sessions and associations between modeling decisions and reliability estimates (e.g., intraclass correlation (ICC), Jaccard similarity) are reported using specification curve analyses and hierarchical linear modeling. In addition to examining whether specific modeling decisions result in higher reliability, this study also evaluates an underexplored issue: How modeling decisions impact within- and between-subject variance and at which sample size the ICC stabilizes in fMRI data

A Multi-Sample Evaluation of the Measurement Structure and Function of the Modified Monetary Incentive Delay Task in Adolescents.

Interpreting the neural response elicited during task functional magnetic resonance imaging (fMRI) remains a challenge in neurodevelopmental research. The monetary incentive delay (MID) task is a popular fMRI reward processing task that is extensively used in the literature. However, modern psychometric tools have not been used to evaluate measurement properties of the MID task with regard to fMRI signals. The current study uses data obtained with a similar task design across three adolescent samples (N = 346 [Mean Age 12.0; 44% Female]; N = 97 [Mean Age 19.3; 58% Female]; N = 112 [Mean Age 20.2; 38% Female]) to evaluate multiple measurement properties of fMRI responses on the MID task. Confirmatory factor analysis (CFA) and exploratory structural equation modeling are used to test and examine an a priori theoretical framework for the task and its measurement invariance across three samples. Exploratory factor analysis (EFA) is then used to identify the data-driven measurement structure within and across the samples. Finally, local structural equation modeling (LSEM) is used to test whether manifest variables of reward processing change as a function of pubertal development. The CFA results suggest that the a priori theoretical framework is a poor representation of these MID task data. Across the samples, the data-driven EFA models consistently identify a six-to-seven factor structure with run and bilateral brain region factors. This factor structure is moderately-to-highly congruent across the three samples and does not significantly vary across pubertal development in a held-out ABCD sample. Altogether, these findings demonstrate a need to evaluate theoretical frameworks for popular fMRI task designs to improve our understanding and interpretation of brain-behavior associations

Ecological stress, amygdala reactivity, and internalizing symptoms in preadolescence: Is parenting a buffer?

Ecological stress during adolescent development may increase the sensitivity to negative emotional processes that can contribute to the onset and progression of internalizing behaviors during preadolescence. Although a small number of studies have considered the link among the complex relations in ecological stress, amygdala reactivity and internalizing symptoms in childhood and adolescence, these studies have largely been small, cross-sectional, and often do not consider unique roles of parenting or sex. In the current study, we evaluated the interrelations among ecological stress, amygdala functioning, subsequent internalizing symptoms, and the moderating roles of parenting and sex, 9- and 10-year old preadolescents from the Adolescent Brain Cognitive Development study (ABCD). A subset of participants who met a priori quality control criteria for bilateral amygdala during the N-back faces versus places contrast (N = 7,385; Mean Age = 120 months, SD = 7.52; 49.5% Female) were included in the study. A Confirmatory Factor Analysis (CFA) was performed to create a latent variable of ecological stress, and multiple Structural Equation Model (SEM) models were conducted to evaluate the association among baseline ecological stress and internalizing symptoms one year later, the mediating role of amygdala activity, and moderating effects of parental acceptance and sex. The results revealed a significant association among ecological stress and subsequent internalizing symptoms, which was greater in males than females. There was no association between amygdala activity and ecological stress or subsequent internalizing symptoms, and no mediating role of amygdala, or moderating effect of parental acceptance, on the association between ecological stress and internalizing symptoms. An alternative mediation model was tested and revealed that parental acceptance mediated the association between ecological stress and internalizing symptoms, demonstrating lower internalizing symptoms among preadolescents one year later. Given the lack of association in brain function, ecological stress and internalizing symptoms in this registered report, effects from small studies should be reconsidered in larger samples

Neural heterogeneity underlying late adolescent reward processing is linked to individual differences in behavioral sensation seeking.

Adolescent risk-taking, including sensation seeking (SS), is often attributed to developmental changes in connectivity among brain regions implicated in cognitive control and reward processing. Despite considerable scientific and popular interest in this neurodevelopmental framework, there are few empirical investigations of adolescent network connectivity–let alone examinations of its links to SS behavior. The studies that have been done focus on mean-based approaches and leave unanswered questions about individual differences in neurodevelopment and behavior. The goal of this paper is to take a person-specific approach to the study of adolescent functional connectivity during reward processing, and to examine links between connectivity and self-reported SS behavior in 104 adolescents (MAge=19.3; SDAge=1.3). Using group iterative multiple model estimation (GIMME), person-specific connectivity during two neuroimaging runs of a monetary incentive delay task was estimated among 12 a priori brain regions of interest representing reward, cognitive, and salience networks. Two data-driven subgroups were detected, a finding that was consistent between both neuroimaging runs, but associations with SS were only found in the first run, potentially reflecting neural habituation in the second run. Specifically, the subgroup that had unique connections between reward-related regions had greater SS and showed a distinctive relation between connectivity strength in the reward network and SS. These findings provide novel evidence for heterogeneity in adolescent brain-behavior relations by showing that subsets of adolescents have unique associations between neural reward processing and SS. Findings have broader implications for future work on reward processing, as they demonstrate that brain-behavior relations may attenuate across runs