Midbrain

00:00 Some features of the midbrain for you to keep in mind as well as some of the functions.

00:06 Superior colliculus is shown here. Again, this will orient the head and the eyes toward a visual stimulus.

00:15 The red nucleus is shown in through here as well as over here. The red nucleus is receiving motor input from two sources, cortex and cerebellum. Then this will help to facilitate flexor movements in the contralateral upper extremity or limb. Some other features of the midbrain that are prominent here would be the presence of the substantia nigra, this black staining substance, black body is the little translation here or black substance. This is a member of the basal ganglia. There’s depigmentation of the substantia nigra due to a loss of dopaminergic neurons. This loss of dopaminergic neurons would characterize Parkinson’s disease. We can also see the anterior portion of the cerebral peduncle here.

01:18 This is the crus cerebri that we mentioned earlier. Additional features of the midbrain would include the cranial nerve III nucleus and the nerve. The nucleus is this slender structure here and here.

01:37 Then in this sectional region, you can see the cranial nerve III actually coming from the midbrain.

01:46 Also, you have the cerebral aqueduct that is shown here. This is a communication between the third ventricle and the fourth ventricle.