1544
Symposium
In the last several years, there has been increased interest in the Precision Mapping investigational approach, which involves collecting detailed measures of brain structure, organization, and function within single individuals. This strategy enables observation of individual-specific features of brain organization previously obscured by group-averaging and facilitates scientific inferences from within-subject designs. Collection of extended datasets following this strategy has become more common and has resulted in a number of recent high impact observations. We believe that it would be timely to present and discuss work using these approaches to the OHBM community.
Thus, we propose a Symposium to cover the current state of Precision Mapping and highlight recent work employing detailed and extensive within-individual neuroimaging designs. The proposed symposium includes a wide diversity of groups from around the globe investigating a number of exciting topics. Specifically, proposed participants will report on Precision Mapping investigations revealing individual-specific brain networks associated with depression; within-individual neural function associated with painful sensations; within-individual longitudinal effects of pregnancy; and individual-specific brain systems engaged during language processing. These presentations will highlight to attendees the wide range of potential applications of the Precision Mapping approach, and, by example, will provide those who may be interested in the approach with an understanding of how to implement Precision Mapping in their own research.
1. What scientific questions can be most ideally investigated using a Precision Mapping approach to neuroimaging?
2. What has recent Precision Mapping work taught us about the function and structure of the individual human brain?
As Precision Mapping has emerged as a major recent theme in the field of neuroimaging with applications in both basic and translational science, these talks will be of broad interest to researchers interested in the latest developments in human brain mapping. This audience includes researchers interested in basic functional neuroanatomy as well as those focused on descriptive and/or interventional studies in clinical populations.
Presentations
Pain experience is personal, and its brain representations exhibit a high degree of individual variability. This poses a challenge in developing a population-level brain biomarker of pain that works for everyone. In this talk, I will introduce our recent efforts to develop personalized neuroimaging markers of pain across two studies. We conducted an extensive sampling approach from a small number of healthy and clinical participants and developed personalized fMRI-based predictive models. Our findings demonstrate that personalized markers outperform group-level models when sufficient data are available for each individual, potentially capturing unique internal factors influencing pain. Moreover, we observed that brain representations of pain change even within individuals over time. These changes likely reflect dynamic internal changes in the brain, whether functional or structural. These findings emphasize the need to understand internal factors for pain better and incorporate them into brain models to enhance their predictive power and clinical relevance.
Precision functional mapping is the practice of delineating functional brain areas or networks and studying brain-behavior relationships within individuals, as opposed to at the group-level, typically using a large amount of fMRI data per-subject acquired longitudinally. In this talk, I will describe how we applied precision functional mapping in adults with unipolar and bipolar depression who were densely-sampled (serial clinical assessments, fMRI) up to 1.5 years. This work revealed that the salience network is expanded nearly 2-fold in cortex relative to healthy controls due primarily to borders of the network shifting outwards and encroaching upon neighboring functional systems. This expansion was trait-like – stable over time, regardless of fluctuations in mood state. In contrast, functional connectivity strength in particular fronto-striatal circuits tracked fluctuations in symptom severity and mood state switches (transitioning from a euthymic state to depressed or hypomanic episode) within these individuals. Together, these findings reveal new patterns of functional network topology and connectivity that are neural traits and states, respectively, characteristic of mood disorders, and highlight the utility of deeper characterizations of functional neuroanatomy and behavior within individuals as an alternative to studying population-level central tendencies.
High-level cognitive systems, such as language, show vast inter-individual variability in their precise topographical localization. Traditional analytical approaches which interpret observed activations based on their coarse-level anatomical localization and the function associated with that location by previous studies, fail to account for this topographical variability. These challenges may be circumvented by employing functional localization in a precision imaging paradigm. This approach identifies functional entities in the brain of each individual, capturing variability in the brain’s functional topography and allowing for rich and systematic characterization of each area’s function.
This talk will discuss the application of precision functional localization to study the language system and its relationship with neighboring, yet functionally distinct, speech perception and speech production systems. First, I will show that functional localization provides a more precise alternative to study language compared to approaches based on group-level averaging and referring to standard anatomical parcellations, as the language system does not necessarily align with anatomical boundaries in the brain. Second, I will demonstrate how functional localization allows us to precisely disentangle high-level language from systems supporting speech perception and articulation, addressing questions of their functional profiles as well as topographical overlap.
Presenter
Agata Wolna, Ph.D., Massachusetts Institute of Technology Boston, MA
United States
The brain is an endocrine organ whose day-to-day function is shaped by the rhythmic production of neuromodulatory hormones. Yet, traditional cross-subject approaches to studying brain–hormone relationships often miss a central feature of the mammalian endocrine system: hormone production ebbs and flows over time. This talk will highlight emerging evidence of sex hormones’ potent influence on structural and functional properties of the human brain. These discoveries were made possible by closely monitoring single individuals across endocrine transitions, including the circadian cycle, menstrual cycle, and pregnancy. For example, in a recent precision imaging study of pregnancy sweeping changes in white matter microstructure, grey matter volume and cortical thickness were evident week-by-week across gestation, demonstrating the brain’s capacity for extensive neural remodeling well into adulthood. Together, these findings suggest that neuroendocrine factors rapidly and dynamically influence the mammalian brain. Precision imaging designs offer scientists the unique ability to probe these dynamic interactions for the first time.
Presenter
Emily Jacobs, PhD, University of California, Santa Barbara Santa Barbara, CA
United States