Routes of the thalamus through the history of neuroanatomy

[Display omitted] •Neuroanatomy history traces back to Antiquity, with 1st human vivi/dissections.•Before Galen, 2nd century CE, the thalamus is not a brain region and is not named.•After printing invention (∼1450), macroscopic drawings of thalamus become splendid.•With new techniques, a giant leap of thalamic anatomy after the mid-19th century.•A growing number of nuclei isolated but no consensus on limits and connectivity. The most distant roots of neuroanatomy trace back to antiquity, with the first human dissections, but no document which would identify the thalamus as a brain structure has reached us. Claudius Galenus (Galen) gave to the thalamus the name ‘thalamus nervorum opticorum’, but later on, other names were used (e.g., anchae, or buttocks-like). In 1543, Andreas Vesalius provided the first quality illustrations of the thalamus. During the 19th century, tissue staining techniques and ablative studies contributed to the breakdown of the thalamus into subregions and nuclei. The next step was taken using radiomarkers to identify connections in the absence of lesions. Anterograde and retrograde tracing methods arose in the late 1960s, supporting extension, revision, or confirmation of previously established knowledge. The use of the first viral tracers introduced a new methodological breakthrough in the mid-1970s. Another important step was supported by advances in neuroimaging of the thalamus in the 21th century. The current review follows the history of the thalamus through these technical revolutions from Antiquity to the present day.