Which part of the brain connects the right and left hemispheres allowing communication between the two?. . A diagram of the parts of the brain. The following areas are labeled: Cerebral cortex, corpus callosum, hypothalamus, thalamus, cerebellum, spinal cord, medulla oblongata, pons, brain stem, and pituitary.. Answer. . Brain stem. . Cerebral cortex. . Corpus callosum. . Medulla oblongata