tegmentální

Tegmentální, in English tegmental, refers to the tegmentum, a major region of the brainstem. In the midbrain (mesencephalon), the tegmentum lies between the tectum (the dorsal roof) and the cerebral peduncles (basis pedunculi) ventrally, forming the central part of the midbrain. The tegmentum continues into the lower brainstem, including the pons, where it constitutes the dorsal portion of that segment as well.

The tegmentum contains a diverse set of structures. Notable components include the oculomotor nerve nucleus and its accompanying Edinger–Westphal nucleus, the red nucleus, the substantia nigra (pars compacta and pars reticulata), the periaqueductal gray surrounding the cerebral aqueduct, the reticular formation, and various cranial nerve nuclei. It also houses several ascending sensory pathways, autonomic-related centers, and interconnected nuclei that participate in motor control, arousal, pain modulation, and autonomic regulation.

Functionally, the tegmentum serves as an integrative hub within the brainstem. It contributes to eye movements, motor coordination, sensory processing, autonomic functions, and vigilance. It acts as a relay and processing center for multiple motor and sensory pathways that connect the brain with the spinal cord and higher brain regions.

Clinical relevance arises from lesions affecting the tegmentum. Midbrain tegmental lesions can produce oculomotor disturbances and contralateral motor signs, and they may be part of classic syndromes such as Weber or Benedikt, depending on the exact structures involved. The term tegmentální is the Czech adjective form describing anything related to the tegmentum.

Etymology: tegmentum derives from Latin teg- “covering” and mentum, reflecting its anatomical position as a covering-like central part of the brainstem.