Physical changes in the brain have been identified in some people with schizophrenia. The analysis of brain tissue after death has revealed a number of structural abnormalities, and new brain-imaging techniques have revealed changes in both the structure and function of the brain during life. Techniques such as magnetic resonance imaging (MRI) reveal changes in the size of different parts of the brain, especially in the temporal lobes. The fluid-filled spaces (the ventricles) in the interior of the temporal lobes are often enlarged and the temporal lobe tissue diminished. The greater the observed changes the greater the severity of the person’s thought disorder and his or her auditory hallucinations. Show Some imaging techniques, such as positron emission tomography (PET), measure the actual functioning of the brain and provide a similar picture of abnormality. PET scanning reveals hyperactivity in the temporal lobes, particularly in the hippocampus, a part of the temporal lobe concerned with orientation and very short-term memory. Another type of functional imaging, electrophysiological brain recording using EEG tracings, shows that most people with schizophrenia seem to be excessively responsive to repeated environmental stimuli and more limited in their ability to blot out irrelevant information. In line with this finding, those parts of the brain that are supposed to screen out irrelevant stimuli, such as the frontal lobe, show decreased activity on PET scan. Tying in with this sensory screening difficulty, post-mortem brain tissue examination has revealed problems in a certain type of brain cell? the inhibitory interneuron. These neurons damp down the action of the principal nerve cells, preventing them from responding to too many inputs. Thus, they prevent the brain from being overwhelmed by too much sensory information from the environment. The chemical messengers or neurotransmitters (primarily gamma-amino butyric acid or GABA) released by these interneurons are diminished in the brains of people with schizophrenia, suggesting that there is less inhibition of brain overload. Abnormality in the functioning of these interneurons appears to produce changes in the brain cells which release the neurotransmitter dopamine. The role of dopamine has long been of interest to schizophrenia researchers, because drugs such as amphetamines that increase dopamine’s effects can cause psychoses that resemble schizophrenia, and drugs that block or decrease dopamine’s effect are useful for the treatment of psychoses. Dopamine increases the sensitivity of brain cells to stimuli. Ordinarily, this heightened awareness is useful in increasing a person’s awareness during times of stress or danger, but, for a person with schizophrenia, the addition the effect of dopamine to an already hyperactive brain state may tip the person into psychosis. These findings suggest that in schizophrenia there is a deficit in the regulation of brain activity by interneurons, so that the brain over-responds to the many signals in the environment and lacks the ability to screen out unwanted stimuli. This problem is made worse by a decrease in the size of the temporal lobes, which ordinarily process sensory inputs, making it more difficult for the person to respond appropriately to new stimuli. People who have schizophrenia may hear voices or see things that aren’t real. But what happens inside the brain of someone who has schizophrenia? Scientists are working to understand that. They’ve found that people who
have the disorder may be more likely to have glitches in their genes that may disrupt brain development. There’s another key brain difference. Studies show that certain brain chemicals that control thinking, behavior, and emotions are either too active or not active enough in people with schizophrenia. Doctors also believe the brain loses tissue over time. And imaging
tools, like PET scans and MRIs, show that people who have schizophrenia have less “gray matter” -- the part of the brain that contains nerve cells -- over time. This research is helping efforts to develop better treatments for people who have this condition. Doctors don’t know what
causes schizophrenia. It could be passed down in families, but not everyone who has schizophrenia has a close relative (like a parent, brother, or sister) with the condition. Some researchers believe that problems with brain development may be partly responsible for schizophrenia. Others believe that inflammation in the brain may damage cells that are used
for thinking and perception. Many other things could also play a role, including: Scientists don’t know if these things trigger the disorder. But they do know that schizophrenia tends to show up in people around late adolescence or early adulthood. It usually causes a similar set of symptoms, but it can happen differently from person to
person. Two brain chemicals, dopamine and glutamate, carry messages to cells along brain pathways that doctors believe control thinking, perception, and motivation. Dopamine gets a lot of attention in brain research because it’s been linked to addiction. It also plays a role in other psychiatric and movement disorders, like Parkinson’s disease. In schizophrenia, dopamine is tied to
hallucinations and delusions. That’s because brain areas that "run" on dopamine may become overactive. Antipsychotic drugs stop this. Glutamate is a chemical involved in the part of the brain that forms memories and helps us learn new things. It also tells parts of the brain what to do. One study
found that people who are at risk for developing schizophrenia may have too much glutamate activity in certain areas of the brain at first. As the disease progresses, those brain areas may have too little glutamate activity. Doctors are working to find out how brain circuits that use these chemicals work together or are related to each other. Thanks to technology, doctors can see changes in specific areas of
the brain. They can also map the possible loss of brain tissue. One study showed that brain tissue loss in young people at risk of developing the illness was linked to psychotic symptoms like hallucinations. Another study compared MRI pictures of the brains of youths about age 14 who had no symptoms of schizophrenia with those who did. It found that the teens who had symptoms lost more brain tissue over a 5-year period than the others. Research shows that adults who have schizophrenia also may lose gray matter. The Default Mode NetworkWhen we’re just hanging out -- the dishes are done, we’ve finished our homework, or we've completed a tough project at work -- our thoughts are free to roam. This “default mode” allows us time to daydream, reflect, and plan. It helps us to process our thoughts and memories. Scientists call this the default mode network. When we’re not focused on a given task, it “lights up." If you have schizophrenia, your default mode network seems to be in overdrive. You may not be able to pay attention or remember information in this mode, one study shows. OutlookResearchers are working on new medications for the disorder. At least one tackles the glutamate factor. People with schizophrenia have also had some positive results using sarcosine, a chemical that is thought to regulate glutamate. But doctors aren’t sure whether it could help over the long term. So although schizophrenia has no cure and sometimes may get worse over time, the right medications, combined with therapy, can help control the symptoms. What is the difference between a schizophrenic brain and a normal brain?Brain imaging shows that people with schizophrenia have less gray matter volume, especially in the temporal and frontal lobes. These areas of the brain are important for thinking and judgment. What's more, gray matter loss continues over time.
Can you see schizophrenia on a brain scan?Can a brain scan show schizophrenia? It is not currently possible to determine that a person has schizophrenia simply by looking at a brain scan, but certain changes in the brain that can be observed on a brain scan have been associated with schizophrenia.
What happens to the brain of a schizophrenic?Studies show that certain brain chemicals that control thinking, behavior, and emotions are either too active or not active enough in people with schizophrenia. Doctors also believe the brain loses tissue over time.
What does a schizophrenic brain scan look like?In patients with schizophrenia, MR imaging shows a smaller total brain volume and enlarged ventricles. Specific subcortical regions are affected, with reduced hippocampal and thalamic volumes, and an increase in the volume of the globus pallidus.
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What does a schizophrenic brain look like
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