2025 Hyper Recent •CC0 1.0 Universal

This work is dedicated to the public domain. No rights reserved.

Access Preprint From Server
April 3rd, 2025
Version: 1
University of Eastern Finland
neuroscience
biorxiv

Data-driven classification of tissue water populations by massively multidimensional diffusion-relaxation correlation MRI

Narvaez, O.Open in Google Scholar•Yon, M.Open in Google Scholar•Salo, R. A.Open in Google Scholar•Kyyriäinen, J.Open in Google Scholar•Estela, M.Open in Google Scholar•Paasonen, E.Open in Google Scholar•Topgaard, D.Open in Google Scholar•Sierra, A.Open in Google Scholar

Massively multidimensional diffusion-relaxation correlation MRI provides detailed information on tissue microstructure by analyzing water populations at a sub-voxel level. This method correlates frequency-dependent tensor-valued diffusion MRI with longitudinal and transverse relaxation rates, generating nonparametric D({omega})-R1-R2 distributions. Traditionally, D({omega})-R1-R2 distributions are separated using manual binning of the diffusivity and anisotropy space to differentiate white matter (WM), gray matter (GM), and free water (FW) in brain tissue. However, while effective, this approach oversimplifies complex tissue fractions and does not fully utilize all available diffusion-relaxation parameters. In this study, we implemented an unsupervised clustering approach to automatically classify WM, GM, and FW and explore additional water populations using all components in the D({omega})-R1-R2 distributions on ex vivo and in vivo rat brain, and in vivo human brain. Results showed that a basic separation of WM, GM, and FW is possible using unsupervised clustering even under different multidimensional diffusion-relaxation protocols of rat brain and human brain. Additionally, when there is high frequency-dependent diffusion range, it is possible to obtain a cluster characterized by restriction localized in specific high cell density regions such as the dentate gyrus and cerebellum of rat brain. These findings were compared with rat histological sections of myelin and Nissl stainings. We demonstrated that unsupervised clustering of diffusion-relaxation MRI data can reveal tissue complexity beyond traditional WM, GM, and FW segmentation in rat and human brain without parameter assumptions. The unsupervised cluster approach could be used in other body parts (e.g., prostate and breast cancer) without requiring pre-defined bin limits. Furthermore, the characterization of the clusters by diffusivities, anisotropy, and relaxation rates can provide a better understanding of the subtle changes in different cellular fractions in tissue-specific pathologies.

Similar Papers

biorxiv
Fri Apr 04 2025
Audiovisual processing is selectively impaired in the primary visual cortex but not in the posterior parietal cortex of a mouse model of Fragile X syndrome
Sensory processing disruptions are a common feature in various forms of autism spectrum disorders (ASD), yet the circuit-level mechanisms underlying these deficits remain poorly understood. Here, we examined differences in audiovisual processing between wild-type and Fmr1-knockout (KO) mice, a model of Fragile X syndrome, which itself represents the most common hereditary cause of autism. We perfo...
Montelisciani, L.
•
Bosman, C. A.
•
Olcese, U.
biorxiv
Fri Apr 04 2025
Prominent white matter related abnormalities associated with diverse molecular alterations in a mouse model of Col4a1 cerebral small vessel disease.
White matter abnormalities are a central feature of cerebral small vessel disease (cSVD) and underpin cognitive impairment and dementia but their mechanistic link remains poorly understood. To provide insight we studied mice (Col4a1+/Svc) with a mutation in the gene Col4a1 as an established model of cSVD due to collagen IV mutations. Since collagen IV is a key component of the basement membrane, a...
Brezzo, G.
•
Pokhilko, A.
•
Moss, J.
•
Koudelka, J.
...•
Horsburgh, K.
biorxiv
Fri Apr 04 2025
Embodied decisions as active inference
Decision-making is often conceptualized as a serial process, during which sensory evidence is accumulated for the choice alternatives until a certain threshold is reached, at which point a decision is made and an action is executed. This decide-then-act perspective has successfully explained various facets of perceptual and economic decisions in the laboratory, in which action dynamics are usually...
Priorelli, M.
•
Stoianov, I. P.
•
Pezzulo, G.
biorxiv
Fri Apr 04 2025
Attentional engagement with target and distractor streams predicts speech comprehension in multitalker environments
Understanding speech while ignoring competing speech streams in the surrounding environment is challenging. Previous studies have demonstrated that attention shapes the neural representation of speech features. Attended streams are typically represented more strongly than unattended ones, suggesting either enhancement of the attended or suppression of the unattended stream. However, it is unclear ...
Barchet, A. V.
•
Bruera, A.
•
Wend, J.
•
Rimmele, J. M.
...•
Hartwigsen, G.
biorxiv
Fri Apr 04 2025
Mice lacking the endocannabinoid-synthesizing enzyme NAPE-PLD exhibit sex-dependent dysregulations in responsiveness to oxycodone and a natural reward
The endogenous opioid and endogenous cannabinoid (endocannabinoid) systems are highly interconnected in the context of drug reward. Bioactive lipids known as N-acylethanolamines (NAEs), and, specifically, anandamide (AEA), influence several unwanted side effects of opioids, including dependence and tolerance. AEA undergoes degradation by the enzyme fatty-acid amide hydrolase (FAAH), whereas the bi...
Woodward, T. J.
•
Sizemore, E. F.
•
Balaji, A.
•
Port, A. L.
...•
Hohmann, A. G.
biorxiv
Fri Apr 04 2025
Brain Network Segregation is Associated with Drug Use Severity in Individuals with Opioid Use Disorder
Opioid use disorder (OUD) is associated with altered brain network connectivity, particularly in the fronto-parietal (FPN), default mode, and salience (SN) networks. At rest, brain networks that are distinct from each other but are partially connected can optimize neural efficiency and support cognitive performance. Previous research found lower network segregation in people with cognitive impairm...
Hager, N. M.
•
Wang, X.
•
Ramos-Ralon, A. P.
•
Childress, A. R.
...•
Shi, Z.
biorxiv
Fri Apr 04 2025
Novel multi-transmitter calyx-like giant synapse revealed in the extended amygdala
The calyx of Held, a giant excitatory cup-like axo-somatic synapse, has been historically described exclusively in the auditory brainstem. Here, using PACAP immunohistochemistry combined with confocal and tomographic electron microscopy, we report the discovery of a morphologically similar calyx-like synapse in the extended amygdala of rodents, exhibiting unique neurochemical features. This previo...
Zhang, L.
•
Hernandez, V.
•
Giraldo, D. M.
•
Leon-Contreras, J. C.
...•
Eiden, L. E.
biorxiv
Fri Apr 04 2025
Purkinje cell branch morphology determines effect of inhibition and SK2 modulation on somatic pauses
Characterized by a highly complex branching of their dendrites, Purkinje cells (PCs) have a unique architecture that enables them to receive impressive amounts of sensorimotor information through their parallel fiber (PF) input. They are tasked to encode this information with high accuracy. In this work, we discuss the mechanisms through which PCs encode this information, and we show how they mult...
Chou, P.-J.
•
De Schutter, E.
•
Cirtala, G.
biorxiv
Fri Apr 04 2025
Dual-site beta transcranial alternating current stimulation during a bimanual coordination task modulates functional connectivity between motor areas
Background: Communication within brain networks depends on functional connectivity. One promising approach to modulate such connectivity between cortical areas is dual-site transcranial alternating current stimulation (tACS), which non-invasively applies weak alternating currents to two brain areas. Objectives/Hypotheses: In the current study, we aimed to modulate inter-regional functional connect...
Gann, M. A.
•
Paparella, I. A.
•
Zich, C.
•
Grigoras, I.
...•
Schwab, B. C.
biorxiv
Fri Apr 04 2025
BABA: Naturalistic fMRI and MEG recordings during viewing of a reality TV show
Recent advances in the cognitive neuroscience of language have embraced naturalistic stimuli such as movies and audiobooks. However, most open-access neuroimaging datasets still focus on single-speaker scenarios, falling short of capturing the complexity of real-life, multi-speaker communication. To address this gap, we present the BABA fMRI and MEG dataset, collected while participants watched a ...
Li, J.
•
Wang, Q.
•
Wang, Y.
•
Wang, C.
...•
Meng, Z.