The Mystery of the Claustrum, the Front Wall of the Brain: From Early Anatomic Discovery to Modern Insights.
Demet Evleksiz, Abuzer Gungor, Gardashkhan Karımzada, Betul Yaman, Aynaz A Kara, Yusuf Izci, Wolfgang J Weninger, Uğur Türe
World neurosurgery May 8, 2025 DOI: 10.1016/j.wneu.2025.124045 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Peer reviewed |
|---|---|
| Topics | Philosophy of mind |
| Keywords | Claustrum Gray matter Insula Neuroanatomy Terminology Brain anatomy Historical neurology |
| Citations | 4 |
| Key findings | The claustrum's exact function remains debated; neurosurgical evidence indicates that damage to the claustrum does not impair consciousness, contradicting earlier proposals of its essential role in consciousness. |
Abstract
The claustrum, a thin layer of gray matter between the insular cortex and putamen, has been a subject of anatomical and functional curiosity for centuries. Although early anatomical descriptions provide some insights, modern neuroimaging and neurosurgical studies have reignited interest in its structure and function. This study examines the historical evolution of the claustrum's terminology and clinical significance. A comprehensive review was conducted, analyzing neuroanatomical texts from the 15th to 20th centuries and contemporary academic publications on the claustrum. The investigation focused on anatomical descriptions, variations in nomenclature, and the claustrum's neurosurgical significance. The first known depiction of the claustrum appeared in the work of Vicq d'Azyr (1786), followed by formal naming as the vormauer (claustrum) by Burdach (1822). Subsequent terminology included N. taeniaeformis (Arnold, 1838) and avant-mur (Dejerine, 1895). Neurodevelopmental research by Puelles (2017, 2022) provided genetic evidence distinguishing it from adjacent structures. Functionally, Crick and Koch (2005) proposed its role in consciousness as a sensory integrator. Still, Yaşargil's neurosurgical observations indicate that tumor invasion or iatrogenic damage of the claustrum in cases of insular glioma does not result in impaired consciousness, prompting a reassessment of its functional role. This review synthesizes historical and contemporary perspectives to highlight the claustrum's relevance in neuroscience and neurosurgery. Although its exact function remains debated, ongoing research continues to shed light on its role in brain connectivity and integration. Understanding the claustrum's structure and function may lead to novel insights into sensory processing, cognition, and potential neurosurgical applications.