Exam 1: Brainstem

brainstem (location? function? comprised of?)

• lowest part of the brain (just below the thalamus), connecting it with the spinal cord, which carries essential basic functions such as respiratory or heart regulation

• has 3 main parts: midbrain, pons, and medulla oblongata

midbrain (position? function?)

• contains different nuclei, including…

  • the superior colliculi - they receive the visual input and are important for eye gaze

  • inferior colliculi - they receive auditory input and are important for the startle response and orienting to novelty

  • respiratory nuclei

  • the tracts to and from the cerebellum

• superior to the pons

pons (position? function?)

• contains tracts that transmit signals between the cerebrum and cerebellum

• includes the nuclei responsible for breathing, sleep cycles (REM sleep), arousal, etc

• superior to the medulla oblongata and inferior to the midbrain

medulla oblongata (position? function?)

• most caudal (inferior) portion of the brainstem and is continuous with the spinal cord

• controls a range of vital functions such as respiration, heart rate, blood pressure, and reflexes (such as vomiting, coughing, sneezing, etc)

What’s the connection with the medulla oblongata and the blood-brain barrier?

The blood-brain barrier is very weak/missing in the area postrema, which makes it possible to detect any poisonous/toxic content in the blood. This can be life-saving when the vomiting center is activated and the stomach is emptied of the toxic substance.