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Brain: Difference between revisions
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The [[Brain]] is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. The brain is located in the head, usually close to the sensory organs for senses such as vision. The brain is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 15–33 billion [[Neurons]], each connected by synapses to several thousand other neurons. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. | The [[Brain]] is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. The brain is located in the head, usually close to the sensory organs for senses such as vision. The brain is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 15–33 billion [[Neurons]], each connected by synapses to several thousand other neurons. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. | ||
Physiologically, the function of the | 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 the 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. | ||
The operations of individual brain cells are now understood in considerable detail but the way they cooperate in ensembles of millions is yet to be solved. Recent models in modern [[Neurobiology|neuroscience]] treat the brain as a biological computer, very different in mechanism from an electronic computer, but similar in the sense that it acquires information from the surrounding world, stores it, and processes it in a variety of ways.<ref>[https://en.wikipedia.org/wiki/Brain Brain]</ref> | The operations of individual brain cells are now understood in considerable detail but the way they cooperate in ensembles of millions is yet to be solved. Recent models in modern [[Neurobiology|neuroscience]] treat the brain as a biological computer, very different in mechanism from an electronic computer, but similar in the sense that it acquires information from the surrounding world, stores it, and processes it in a variety of ways.<ref>[https://en.wikipedia.org/wiki/Brain Brain]</ref> | ||
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==Left and Right hemisphere== | ==Left and Right hemisphere== | ||
The left hemisphere of the brain is the self-cognitive, verbal and linear reasoning component of the mind. It fulfills the function of screening incoming stimuli by categorizing, assessing and assigning meaning prior to allowing passage of that content to the right hemisphere of the brain. The right hemisphere functions as the non-critical, holistic, non-verbal and pattern oriented component of the brain and tends to automatically accept the content passed from the left hemisphere without question. Both the sensory and motor cortices of the right cerebral portion of the brain contain sequences of points known as the [[Homunculus]], which corresponds to points in the body. Stimulation of these corresponding areas on the cortex causes immediate responses in the associated portion of the body. Consequently, if there is an induction of suggestion through an stimulus that the left leg is numb, if it reaches the right hemisphere unchallenged and is referred to the appropriate area of the sensory cortex, this will result in an electrical reaction being generated that will induce the feeling of numbness in the left leg. <ref> | The left hemisphere of the brain is the self-cognitive, verbal and linear reasoning component of the mind. It fulfills the function of screening incoming stimuli by categorizing, assessing and assigning meaning prior to allowing passage of that content to the right hemisphere of the brain. The right hemisphere functions as the non-critical, holistic, non-verbal and pattern oriented component of the brain and tends to automatically accept the content passed from the left hemisphere without question. Both the sensory and motor cortices of the right cerebral portion of the brain contain sequences of points known as the [[Homunculus]], which corresponds to points in the body. Stimulation of these corresponding areas on the cortex causes immediate responses in the associated portion of the body. Consequently, if there is an induction of suggestion through an stimulus that the left leg is numb, if it reaches the right hemisphere unchallenged and is referred to the appropriate area of the sensory cortex, this will result in an electrical reaction being generated that will induce the feeling of numbness in the left leg. <ref>Report-Dept. of Army Analysis and Assessment of Gateway Process, June 9, 1983, LTC Wayne M. McDonnell</ref> | ||
==References== | ==References== | ||