In which area of the brain would one find the tectum, tegmentum, superior and inferior colliculi, and substantia nigra?

Mid brain

Explanation:

The midbrain is the part of the brain that extends from the pons to the diencephalon. The ventral part of the midbrain is tegmentum. It is mainly involved in reflexes and movement of the body. Tectum is the posterior part of the midbrain and has four rounded elevations. The two superior elevations make the superior colliculi. They serve as reflex centers for specific activities related to vision.

The two inferior elevations make the inferior colliculi. They are involved in the auditory pathway. The large and dark-colored nuclei other than the colliculi are left and right substantia niagra. Dopamine releasing neurons extend from the substantia nigra to the basal nuclei.