BRAIN: the CPU of Human Beings

The brain is the center of the nervous system in all vertebrate and most invertabrate animals—only a few invertebrates such as sponges and jellyfishes , even if diffuse neural tissue is present. Physiologically, the function of the brain is to exert centralized control over the other organs of the body. The brain acts on the rest of the body both by generating patterns of muscle activity and by driving secretion of chemicals called hormones. This centralized control allows rapid and coordinated responses to changes in the environment. Some basic types of responsiveness such as reflexes can be mediated by the spinal cord or peripheral ganglia, but sophisticated purposeful control of behavior based on complex sensory input requires the information-integrating capabilities of a centralized brain.


Lobes of the Brain: 

1. Frontal lobe—conscious thought; damage can result in mood changes, social differences, etc. The frontal lobes are the most uniquely human of all the brain structures.
2. Parietal lobe—plays important roles in integrating sensory information from various senses, and in the manipulation of objects; portions of the parietal lobe are involved with visuospatial processing
3. Occipital lobe—sense of sight; lesions can produce hallucinations
4. Temporal lobe—senses of smell and sound, as well as processing of complex stimuli like faces and scenes.
5. Limbic lobe—emotion, memory