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Preksha Dhyana :
physical accompaniments are integrated by the hypothalasmus, limbic system and prefrontal cortex. Centres of anger, fear, pleasure and pain are located in hypothalamus and elsewhere.
This part of the brain is obviously implicated in the most vital bodily functions, since an injury to it may cause emotional outbrust, over-eating, obesity and reduction of sexual activity.
Cerebellum and Brainstem. The hindbrain comprises of cerebellum and brainstem. The cerebellum, literally meaning 'little brain' sits behind the brainstem below the cerebrum and is concerned with the fine control and regulation of movement and maintaining balance. It looks very much like a small version of tbe cerebrum. It is divided into two hemispheres and is a mixture of grey and white matter.
The cerebral cortex plays a key-role in the control of muscular contractions that move body parts. But the part of the brain that makes sure that each muscle contracts not too much or too little but just enough to carry out cerebrum's intentions is the cerebellum. Damage to the cerebellum results in the loss of equilibrium and the person's movements will become jerky and uncoordinated.
The mid-brain, pons and medulla together are called the orain-stem from their resemblance to the stem of a fruit.
The brainstem connects the cerebrum with the spinal cord. Its uppermost part-the midbrain, is tucked up in the cerebrum. It houses a number of movement coordinating Kentres and is also responsible for sleep and wakefulness. Beneath this is the pons or bridge connecting it with the cerebellum,
Pons is a bridge-like structure, consisting mainly of white matter and serving as a relay station, linking medulla with the higher cortical centres. Finally the medulla oblongata joins the pons to the spinal cord. It is about one inch long portion of the brain-stem. It merges continuously with the spinal cord below and the pons above. Situated there are the centres for the control of key body-functions viz , the cardiac, vaso-constrictor and respiratrory centres.
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