User talk:Sciencegeeks123

Cerebrum

Some researchers believe that addictive disorders, such as substance use disorders and binge eating, may stem from malfunctions in natural brain systems for pleasure and well- being. People genetically predisposed to this reward deficiency syndrome may crave whatever provides that missing pleasure or relieves negative feelings (Blum et al., 1996).

Structure of the Cortex If you opened a human skull, exposing the brain, you would see a wrinkled organ, shaped somewhat like the meat of an oversized walnut. Without these wrinkles, a fl attened cerebral cortex would require triple the area—roughly that of a large pizza. The brain’s left and right hemispheres are fi lled mainly with axons connecting the cortex to the brain’s other regions. The cerebral cortex—that thin surface layer—contains some 20 to 23 billion nerve cells and 300 trillion  synaptic  connections  (de  Courten-Myers,  2005). Being human  takes  a  lot  of  nerve. Supporting these billions of nerve cells are nine times as many spidery glial cells(“glue cells”). Neurons are like queen bees; on their own they cannot feed or sheathe themselves. Glial cells are worker bees. They provide nutrients and insulating myelin, guide neural con- nections, and mop up ions and neurotransmitters. Glia may also play a role in learning and thinking. By “chatting” with neurons they may participate in information transmission and memory (Fields, 2009; Miller, 2005) Recticular Formation The recticular formation is a nerve network of nuclei clusters found in the human brain stem. Its dorsal tegmental nuclei are in the midbrain white its central tegmental nuclei are in the pons and its central and inferior nuclei are found in the medulla

Importance of the corpus callosum & it's importance Corpus callosum is a broad band of nerve fibers joining the two hemispheres of the brain. It would be located in the center of the skull if it were created. The Corpus Callosum is part of the mind that allows communication between the two hemispheres of the brain. It is responsible for transmitting neural messages between both right and left hemispheres.

Older brain  networks  sustain  basic  life  functions  and  enable  memory,  emotions,  and  ba- sic drives. Newer neural  networks  within  the cerebrum—the hemispheres  that  contribute 85 percent of the brain’s weight—form specialized work teams that enable our perceiving, thinking, and speaking. Like other structures above the brainstem (including the thalamus, hippocampus, and  amygdala),  the  cerebral  hemispheres  come  as  a  pair. Covering those hemispheres, like bark on a tree, is the cerebral cortex,a thin surface layer of intercon-nected neural  cells. It is  your  brain’s  thinking  crown,  your  body’s  ultimate  control  and information - processing center. As we move up the ladder of animal life, the cerebral cortex expands, tight genetic con- trols relax, and the organism’s adaptability increases. Frogs and other small-cortex amphibians operate extensively on preprogrammed genetic instructions. The larger cortex of mammals of- fers increased capacities for learning and thinking, enabling them to be more adaptable. What makes us distinctively human mostly arises from the complex functions of our cerebral cortex.

Damage to the occipital lobe results in loss of visual capability and an inability to identify colors, also hallucinations. At times someone may experience severe vision loss or total blindness.

More than a century ago, surgeons found damaged cortical areas during autopsies of people who had been partially paralyzed or speechless. This rather crude evidence did not prove that specifi c parts of the cortex control complex functions like movement or speech. After all, if the entire cortex controlled speech and movement, damage to almost any area might produce the same effect. A TV with its power cord cut would go dead, but we would be fool- ing ourselves if we thought we had “ localized ” the picture in the cord. Motor Functions Scientists had  better  luck  in  localizing  simpler  brain  functions. For example,  in  1870,  German physicians Gustav Fritsch and Eduard Hitzig made an important discovery: Mild electrical stimulation to  parts  of  an  animal’s  cortex  made  parts  of  its  body  move. The effects  were  selective: Stimulation caused movement only when applied to an arch- shaped region at the back of the frontal lobe, running roughly ear-to-ear across the top of the brain. Moreover, stimulating parts of this region in the left or right hemisphere caused movements of specifi c body parts on the opposite side of the body. Fritsch and Hitzig had discovered what is now called the motor cortex.

Brain research relies heavily on case studies to learn more about functioning and anatomy in humans. Most brain research would be unethical to perform on both humans and non-human animals, so researchers have to wait for naturally occurring injuries to happen in order to learn more about how the brain works.