Spinal cord—portion of the central nervous system below the level of the medulla.Brain—portion of the central nervous system above the spinal cord.According to the evolutionary model, the brain consists of three sections: reptilian brain
(medulla, pons, cerebellum); old mammalian brain (limbic system, hypothalamus, thala-
mus); and the new mammalian brain (cerebral cortex).
According to the developmental model, it consists of three slightly different sections: the
hindbrain (medulla, pons, cerebellum), the midbrain (small region with parts involved in
eye reflexes and movements), and the forebrain (including the limbic system, hypothala-
mus, thalamus, cerebral cortex).
Convolutions—folding-in and out of the cerebral cortex that increases surface area of
the brain.Contralaterality—control of one side of your body by the other side of your brain.The parts of the brain with the functions associated with each are:
- Medulla oblongata—regulates heart rhythm, blood flow, breathing rate, digestion,
vomiting. - Pons—includes portion of reticular activating system or reticular formation critical
for arousal and wakefulness; sends information to and from medulla, cerebellum, and
cerebral cortex. - Cerebellum—controls posture, equilibrium, and movement.
- Basal ganglia—regulates initiation of movements, balance, eye movements, and pos-
ture. - Thalamus—relays visual, auditory, taste, and somatosensory information to/from
appropriate areas of cerebral cortex. - Hypothalamus—controls feeding behavior, drinking behavior, body temperature,
sexual behavior, threshold for rage behavior, activation of the sympathetic and
parasympathetic systems, and secretion of hormones of the pituitary. - Amygdala—influences emotions such as aggression, fear, and self-protective behav-
iors. - Hippocampus—enables formation of new long-term memories.
- Cerebral cortex—center for higher-order processes such as thinking, planning, judg-
ment; receives and processes sensory information and directs movement. - Association areas—areas of the cerebral cortex that do not have specific sensory or
motor functions, but are involved in higher mental functions such as thinking, plan-
ning, and communicating.
Geographically, the cerebral cortex can be divided into eight lobes, four on the left side and
four on the right side:
- Occipital lobes—primary area for processing visual information.
- Parietal lobes—front strip is somatosensory cortex that processes sensory informa-
tion including touch, temperature, and pain from body parts; association areas per-
ceive objects.
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