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Bonhoeffer, M.

Publications and source records attributed to Bonhoeffer, M..

2 recordsLinked to original sources

An explainable AI latent space of brain dynamics reveals a cerebello-prefrontal signature of schizophrenia symptoms

Schizophrenia presents with several partially independent symptom dimensions, including positive symptoms, negative symptoms, and cognitive impairment; yet no neuroimaging framework has provided individual-level markers of symptom severity that remain anatomically interpretable. Here, we present an interpretable AI-based framework that addresses this gap by mapping high-dimensional resting-state rs-fMRI dynamics onto a low-dimensional latent manifold using self-supervised contrastive learning with a new attribution method to localize the highest decodable regions. Applied to two independent schizophrenia-spectrum cohorts, the label-free latent space supports individual-level prediction across clinical features of the disorder, including symptom severity and cognitive function. The attribution maps identify a disease-specific pathological footprint concentrated in prefrontal, posterior cerebellar and temporal areas that diverge from the manifold organization observed in healthy controls, which was dominated by auditory, limbic, and ventral-striatal circuits. These results establish an interpretable latent space framework for characterizing the distributed neural substrates of schizophrenia symptoms at the level of the individual patient, and provide an anatomically grounded route toward precision decoding of symptom severity.

neuroscience↗

Cerebrospinal fluid flow and clearance driven by lateral ventricle volume oscillations

In the human brain, substance clearance is intimately connected to the cerebrospinal fluid (CSF) and its flow. CSF extends from the lateral ventricles (LVs) to the parenchymas perivascular spaces. Macroscopic undulating CSF flow is present during both wakefulness and sleep and can be experimentally induced. However, the mechanisms generating this flow and its contribution to brain clearance remain unclear. Using fMRI and PET across various conditions, we demonstrate that LV-volume oscillations drive undulating CSF flow in the ventricles and subarachnoid basal cisternae. LV oscillations are driven by cortical blood-volume changes induced by neuronal activity, heartbeat and respiration. LV oscillations amplitudes determine PET-tracer clearance from the LVs. Conclusively, induced by extra- and intracranial physiological drivers and mediated by cortical blood-volume changes, LV-volume oscillations drive macroscopic CSF flow and clearance.

neuroscience↗