Question

The superior colliculi are twin bodies within the corpora quadrigemina of the midbrain that are involved in a. visual reflexes. b. auditory reflexes. c. relaying of cutaneous information. d. release of pituitary hormones.

Short answer

The superior colliculi, within the corpora quadrigemina of the midbrain, are involved in (a) visual reflexes.

Step-by-step solution

Understand the superior colliculi and the corpora quadrigemina

The corpora quadrigemina is a structure in the midbrain, which consists of four colliculi. There are two superior colliculi and two inferior colliculi, forming a total of four rounded eminences. The superior colliculi are involved in specific functions related to the nervous system.

Analyze Option A

Option A states that the superior colliculi are involved in visual reflexes. This is indeed one of the primary functions of the superior colliculi. They receive input from the retina and are involved in coordinating eye movement, as well as other visual reflexes like saccades.

Analyze Option B

Option B states that the superior colliculi are involved in auditory reflexes. This option is not correct because auditory reflexes are managed by the inferior colliculi, not the superior colliculi. The inferior colliculi receive input from the auditory pathway and are responsible for processing auditory information.

Analyze Option C

Option C states that the superior colliculi are involved in the relaying of cutaneous information. This option is also incorrect. The processing and relaying of cutaneous (touch and pain) information is the primary function of the somatosensory system, which includes different areas of the brain and spinal cord, but not the superior colliculi.

Analyze Option D

Option D states that the superior colliculi are involved in the release of pituitary hormones. This option is incorrect as well. The release of pituitary hormones is regulated by the hypothalamus, which is a different structure in the brain, not associated with the superior colliculi.

Conclusion

Based on the analysis of the given options, we can conclude that the superior colliculi are involved in (a) visual reflexes. This is the correct answer for this exercise.