Human Connectome Project

Primary sensory brain areas contain innate stereotyped topographies like retinotopy and somatotopy, but evidence of similar topographies underlying abstract cortical representations remains equivocal. Experience-driven self-organization provides a complementary mechanism for neural circuit development which instead yields conserved features like orientation tuning, but has also mainly been studied in sensory cortices or artificial neural networks (ANNs). Here we pursue a high level perspective on conservation of topographies and feature spaces throughout the cortex using blood oxygen level d

Long-range temporal dependencies (LRTD) are an important signature of computation in the brain. They were shown to be decreased by Alzheimer’s and increased by epilepsy. An established way of capturing the LRTDs is to use Hurst exponents, for which estimation various methodologies were proposed in different fields of study. In neuroscience, LRTDs have been measured in broad-band electro- and magnetoencephalography (E/MEG) [2] (Fig. 1h), amplitude envelopes of oscillations [1] (Fig. 1g), and functional Magnetic Resonance Imaging (fMRI) [3] (Fig. 1f) using several existing methods. Theoretical w

…with multiple fMRI sessions from the Human Connectome Project to gro

Aims. While human neuroscience has traditionally focused on the neocortex, recent literature highlights the key role of subcortical structures in brain dynamics and cognitive processes. We investigated cortico-subcortical interactions in the human brain at rest by analyzing dynamic functional connectivity at rest in a large cohort of healthy human participants.Methods. We considered 1078 human participants from the Human Connectome Project, for which resting-state fMRI scans were available. We computed sliding window functional connectivity (sw-FC) on windows of 60 s. sw-FC matrices were appro

Trends in NeuroAI is a reading group hosted by the MedARC Neuroimaging & AI lab (https://medarc.ai/fmri). Title: SwiFT: Swin 4D fMRI Transformer Abstract: Modeling spatiotemporal brain dynamics from high-dimensional data, such as functional Magnetic Resonance Imaging (fMRI), is a formidable task in neuroscience. Existing approaches for fMRI analysis utilize hand-crafted features, but the process of feature extraction risks losing essential information in fMRI scans. To address this challenge, we present SwiFT (Swin 4D fMRI Transformer), a Swin Transformer architecture that can learn brain dyna

…part of our Neuromatch Academy 2022 project, we used resting state and task-dependent fMRI data from 339 human subjects from the Human Connectome Project (HCP 2020) to quantify the asymmetry of functional connectivity between left and right OFC, and posterior OFC (pOFC) regions during rest and task blocks. We then aimed to relate this asymmetry index (AI) to reward-driven impulsivity traits, quantified by subj

…tasks in a study done by the Human Connectome Project (Binder et. al, 2020). In this study, the subje

Understanding the brain-behavior relationship is a central goal in neuroscience. Recent neuroimaging studies have demonstrated that individual differences in both brain anatomy and the connectivity between regions are predictive of behavior. We hypothesize that behavior can also be predicted by how the same brain region, in different individuals, encodes information. As an analogy, athletic ability is not only related to the size of the components of the cardiovascular and musculoskeletal systems or the strength of the connections between components, it is also related to the proficiency of th

The Group Iterative Multiple Model Estimation (GIMME) framework has emerged as a promising method for characterizing connections between brain regions in functional neuroimaging data. Two of the most appealing features of this framework are its ability to estimate the directionality of connections between network nodes and its ability to determine whether those connections apply to everyone in a sample (group-level) or just to one person (individual-level). However, there are outstanding questions about the validity and stability of these estimates, including: 1) how recovery of connection dir