Beyond the Cortex: Integrated Perspectives on the Claustrum and Enigmatic Subcortical Hubs in Health and Disease.

Despite its thin, sheet-like appearance, the claustrum is one of the most highly connected structures in the mammalian brain, maintaining reciprocal links with almost all areas of the neocortex. While its anatomical prominence has long been recognized, its internal organizational logic and specific contributions to brain-wide communication remain largely enigmatic. Recent advances in molecular profiling, high-resolution imaging, and circuit mapping have begun to reveal a high degree of heterogeneity within the claustrum, suggesting it acts as much more than a simple relay station.

The goal of this Research Topic is to provide a comprehensive, multi-scale understanding of claustral architecture and connectivity. By integrating diverse neuroanatomical methodologies, we aim to establish a unified framework that links the molecular identity of individual neurons to their broader roles in local microcircuits and long-range networks. This collection seeks to move the field toward a functional-anatomical model that explains how the claustrum’s structural properties support its role in cognitive integration and behavioral control.

The scope of this Topic encompasses a broad range of anatomical investigations, from embryonic development and regional specification to the structural changes associated with brain disorders. We encourage submissions that utilize multimodal approaches to map the claustrum’s place within the wider landscape of cortical, thalamic, and basal ganglia systems.
Contributions should focus on one or more of the following subtopics:
o Cell-type diversity and molecular identity using scRNA-seq, in situ hybridization, and immunocytochemistry
o Local microcircuit organization and synaptic ultrastructure
o Long-range connectivity with cortical, thalamic, limbic, and basal ganglia networks
o Developmental origin, regional specification, and anatomical maturation
o High-resolution tractography, atlas-building, and multimodal mapping of deep brain nuclei
o Structural alterations and circuit reorganization in neurological and psychiatric disease
o Functional and behavioral correlates of claustral activity
o Integrated and multimodal approaches to understanding the claustrum

Article types and fees

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Data Report
• Editorial
• FAIR² Data
• General Commentary
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• ... View all formats

Articles that are accepted for publication by our external editors following rigorous peer review incur a publishing fee charged to Authors, institutions, or funders.

Article types

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Data Report
• Editorial
• FAIR² Data
• General Commentary
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• Original Research
• Perspective
• Review
• Systematic Review
• Technology and Code

Keywords: Claustrum, Subcortical nuclei, Comparative neuroanatomy, Cytoarchitecture, Chemoarchitecture, Single-cell RNA sequencing (scRNA-seq), Cell-type diversity, Immunocytochemistry, In situ hybridization, Microcircuit organization, Synaptic ultrastructure, Long

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.