Definition of telencephalon in US English:



  • The most highly developed and anterior part of the forebrain, consisting chiefly of the cerebral hemispheres.

    Compare with diencephalon
    • ‘Repertoire size can be predicted by variance in the sizes of several brain nuclei, which show significant covariation not only with each other but also with the size of the telencephalon or overall brain size.’
    • ‘Similarly, animals that occupy spatially complex environments such as coral reefs also tend to have larger telencephalons.’
    • ‘For example, development of the telencephalon can be divided into these stages: neurectoderm, neural plate, neural tube, forebrain vesicle, evaginated hemispheres, etc.’
    • ‘The telencephalon of living reptiles and birds is expanded laterally, so that it has a distinct heart-shape when viewed dorsally.’
    • ‘Developmentally, estrogens might be synthesized only locally in the telencephalon of male Zebra Finches to masculinize the neural circuits controlling song.’


Late 19th century: from tele- + encephalon.