Functional neuroanatomy of schizophrenia
At this point in time The diagnosis of “schizophrenia” today is made on the basis of subjective data that rely on the patient’s observations and research on his experiences – that is, phenomenological level.
Brain tests after smith patients show that in schizophrenia there can be various neuropathological processes. But new methods used in the practice of neuroimaging are not yet effective enough to reveal such a pathology in this disorder. At their use not fixed and functional, and morphological changes in the brain.
Some functional neuroimaging techniques identify specific changes in the frontostriatal and frontolymbic regions of the brain in schizophrenia. Moreover, these changes were detected at the beginning of the disease, and during the manifestation during the first episode of psychosis.
Neuronal dysfunction underlies cognitive impairment in schizophrenia.
- Dysfunction of the prefrontal cortex in schizophrenia
Many symptoms of schizophrenia associated with the defeat of various areas of the prefrontal cortex. For example, deterioration of working memory and other test scores are associated with insufficient activity dorsolateral prefrontal cortex.
Functional neuroimaging in schizophrenia, confirming a decrease in the activity of the prefrontal dorsolateral locus, which is confirmed by special tests (Perlstein et al., 2003).
Numerous studies indicate increased activity in the dorsolateral prefrontal cortex in patients with schizophrenia. When performing complex tests, for example, split ringtones that require some effort, these changes become more pronounced. With simple tests, an increase in the activity of the cortex of the dorsolateral prefrontal region of the brain is observed; Complicated tests decrease activity of this department, if schizophrenic patients do not perform these tests. (Callicot et al., 2003).
Reduction activity of the dorsolateral prefrontal cortex leads to an executive response deficit in patients with schizophrenia. And the deficit in selecting answers with a corresponding sense of success, with concomitant reward, is associated with the ventral and orbitofrontal areas of the prefrontal cortex. (Chemerinski et al., 2002).
Reduced prefrontal activity associated with reduction responses to stimuli that enhance motivation, as the neural networks of the amygdala, which are projected, are suppressed on the prefrontal region (Paradiso et al., 2003).
Strengthening the motivational aspect when choosing an answer is associated with the lower or orbitofrontal region, which play a role in the process of choosing one or another solution of problems associated with tests for inappropriate behavior.
Healthy people The interaction between the dorsolateral and ventral and prefrontal cortex provides a balance between test responses based on choice and the motivation to inhibit inadequate responses. And in schizophrenic patients, this interaction is destroyed.
In patients with schizophrenia interaction between the lower and dorsal foci of the prefrontal area affects pathological activity in the anterior cingular region, which is also involved in monitoring responses.
These data suggest that dysfunction of the prefrontal cortex is observed in schizophrenia, which leads to clinical and cognitive symptoms.
- Dysfunction of the temporal cortex
Reduced activity of the temporal cortex schizophrenia revealed by many scientists. This is established both by functional neuroimaging , and electrophysiological studies, as well as in the process of conducting auditory tests for selective attention.
A progressive deficit in the activity of the temporal cortex has been identified in schizophrenia by many researchers. Functional neuroimaging and electrophysiological studies also revealed pathological foci. The research results revealed a decrease in ties between the frontal and temporal cortex of the brain that was associated with results of the auditory test.
Functional deficiency of the limbic cortex and pathology of the midbrain
The limbic system of the brain is represented by the area of the cortex on the medial side of both hemispheres of the brain, and includes the amygdala and hippocampus . Limbic system involved in the cognitive process, and also associated with taste, eating behavior, aggression, expression of emotions, sexual behavior.
In patients with schizophrenia, the content of dopamine in the limbic system is increased , especially in the left amygdala of the brain.
Dopamine receptor increase also found in patients with schizophrenia in the area of the visual mound. Based on these data, it can be said that diagnostic methods based on phenomenological level, will soon be a thing of the past.
Hallucinations and delusions as symptoms of schizophrenia
Hallucinations and rave – it is alone of major signs acute frustration psyche . Wrong to call them only signs of schizophrenia, since they can accompany and other mental illnesses. Exactly so at treatment patient having similar symptoms , extremely is necessary thorough medical survey and differentiated diagnostics .
But here we will consider these phenomena exactly in framework given disease, where they are positive ( productive ) symptoms schizophrenia . Thats there is the picture diseases appears what not can be at man in normal.
Let’s start with that hallucinations and delirium in schizophrenia These are signs of acute psychosis that require immediate treatment. qualified psychiatric care. Need to remember that on further course of the disease affects how timely and its acute manifestation was stopped. The faster the patient’s relatives take care of rendering assistance, the more favorable the prognosis. A gross mistake is what for some reason, relatives expect that the symptoms of schizophrenia will disappear yourself, or about there is simply no one to take care of the patient, and then the acute psychotic state continues to progress. Naturally in In this case, it is becoming increasingly difficult to stop it.
Hallucinations in schizophrenia
When diagnosing schizophrenia, auditory hallucinations are most often detected when a person hears those or other sounds or voices that are not in objective reality. Voices most often first comment on a person’s actions, then they can begin to criticize him, threaten him, and by as psychosis unfolds, even ordering to commit those or other actions. It is very dangerous, in first of all, for the patient himself, since he can harm itself or people surrounding it, trying, for example, to be protected from not existing objectively but available in his distorted picture of the world, danger.
Signs of hallucinations :
- the man suddenly becomes silent, starts toto listen to anything
- talking tomyself (here, naturally not include man’s thinking out loud or comments on about anything he perceives or experiences in currently in reality, for example, “Where did this book disappear … “),
- sudden,causelesslaughter,
- increasing closure, inability to focus on
Delusional disorder in schizophrenia
Rave – one more of acute signs of schizophrenia. These are certain beliefs of a person or his conclusions that are not match what surrounds it in reality. This is the most inconsistency of reality – one of The first signs that an idea, a belief are delusional. The second feature of delirium – her sustainability and the fact that no third-party reasonable counterargument given ideas give in
According to statistics, order 80% of people with schizophrenia? suffer from various kinds of delusions.
By Crazy ideas can be different in their content. So, classified:
- Delusion of relationship (observed most often). The person feels like the center of all the phenomena around him and events: the actions of all, even completely unfamiliar and randomly passing people expressing them persons driving past cars and other things.
- Brad of pursuit when the patient is sure that certain people / people / organizations intend to cause him some damage, are watching or are already causing some harm (neighbors are poisoned by gas, relatives pour in food poison and other).
- Nonsense effects (mental or physical), when a person is convinced that his thoughts, actions, experiences are not connected with his inner personal motives as well are the result of the influence of some external force: witchcraft, hypnosis, cosmic rays.
Less common but So other types of nonsense can occur.
The productive symptoms of schizophrenia may increase gradually or appear suddenly. Regardless the rate of unfolding of such an acute condition in schizophrenia, you must immediately apply for medical care. Remember: a person with such manifestations of the disease is often not able to ask about aid because the picture of the world and perception of his own state for him is very much distorted. Especially if this is the first attack, the manifestation of schizophrenia.
High-quality relief of such conditions is impossible outside the hospital. The sooner assistance is provided, the more favorable the further forecast will be.
State of the Vegetative Nervous System in Schizophrenia
In patients with schizophrenia, especially before the period of psychosis and in the subacute period, there are changes in the vegetative nervous system. This requires attention during the diagnosis and treatment of a mental disorder.
The first sign of the development of schizophrenia is a dysfunction of the autonomic nervous system. This is manifested in the presence of pathological processes in the cardiovascular system, gastrointestinal tract, sleep disturbance, sleep cycle disturbance – sleep / wakefulness, etc. Therefore, when psychosis occurs, it is necessary to prescribe medications that affect the autonomic nervous system.
The results of studying the parameters of the autonomic nervous system in patients with schizophrenia indicate that they have a predominant parasympathetic system over the sympathetic one.
Of course, the appointment of substances toning the sympathetic nervous system should reduce the symptoms of schizophrenia, however, at the peak of psychosis, fluctuation in tone and predominance of the sympathetic nervous system over the parasympathetic with affective-delusional symptoms, also increased parasympathetic nervous system – with catatonia, which reduces the effectiveness of sympatomimetic drugs and prompts the use of drugs that stimulate the parasympathetic system. It follows from this that the use of sympathicotonics during remission of schizophrenia may occur with the aim of preventing the recurrence of psychosis. It is known that medications of the vagoparalytic group, in particular atropine, were previously used in the treatment of neurosis-like , sluggish forms of schizophrenia, and pilocarpine could provoke a relapse of psychosis.
Observations on patients with schizophrenia during remission showed that the duration of remission can be predicted by the severity of the tone of the sympathetic nervous system.