The hippocampus is part of the limbic system of the brain—a system that is responsible for many aspects of human functioning, including emotions and memory. The frontal lobe, which controls inhibition and attention, helps regulate executive function. The basal ganglia are situated at the base of the forebrain and are mainly comprised of striatum, the globus pallidus, the substantia nigra, the nucleus accumbens, and the subthalamic nucleus. They are associated with voluntary movement, procedural learning, and emotions, but not associated with episodic memory as the hippocampus is. The occipital lobe of the brain is at the back of the head, and is primarily associated with vision. Last, the cerebral aqueduct is part of the ventricular system in the brain and has nothing to do with higher processing.