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Interesting Facts About Brain
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The human brain has many properties that are common to all vertebrate brains, including a basic division into three parts called the forebrain, midbrain, and hindbrain, each with fluid-filled ventricles at their core, and a set of generic vertebrate brain structures including the medulla oblongata, pons, cerebellum, optic tectum, thalamus, hypothalamus, basal ganglia, olfactory bulb, and many others.
As a mammalian brain, the human brain has special features that are common to all mammalian brains, most notably a six-layered cerebral cortex and a set of structures associated with it, including the hippocampus and amygdala. All vertebrates have a forebrain whose upper surface is covered with a layer of neural tissue called the pallium, but in all except mammals the pallium has a relatively simple three-layered cell structure. In mammals it has a much more complex six-layered cell structure, and is given a different name, the cerebral cortex. The hippocampus and amygdala also originate from the pallium, but are much more complex in mammals than in other vertebrates.
As a primate brain, the human brain has a much larger cerebral cortex, in proportion to body size, than most mammals, and a very highly developed visual system. The shape of the brain within the skull is also altered somewhat as a consequence of the upright position in which primates hold their heads.
As a hominid brain, the human brain is substantially enlarged even in comparison to the brain of a typical monkey. The sequence of evolution from Australopithecus (four million years ago) to Homo sapiens (modern man) was marked by a steady increase in brain size, particularly in the frontal lobes, which are associated with a variety of high-level cognitive functions.
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