Schizophrenia is a psychotic spectrum disorder characterized by positive symptoms (hallucinations, delusions, disorganized thoughts?), Negative symptoms (apathy, anhedonia?) And cognitive symptoms (p. E. g. , Attention Disorders). It is a chronic and highly disabling disorder, the object of interest to many authors of different disciplines. In this article, we will discover the types of schizophrenia of Crow, an English psychiatrist born in 1938, who in 1980 distinguished two variants of this disorder as a result of his research.
The classification of Timothy Crow (1938-) is important because it lists the different factors of the medical model (syndrome, evolution, etiology, treatment, prognosis?). The author first distinguished type I schizophrenia (positive) and type II schizophrenia (negative). ).
- However.
- Seven years later.
- In 1987.
- It reformulated its classification.
- Considering that not all cases fall within its dichotomical classification.
- Including also mixed types of schizophrenia.
Although T. Crow’s categorical model is currently out of use, its proposal was very interesting, to this day there are still professionals who find it useful (practical and academic), in addition its classification allows to know more about the reality of this However, what are the two types of schizophrenia of Crow?What’s the difference between them?
“Schizophrenia is the price homo sapiens had to pay for language acquisition. “Timothy Crow?
As we have seen, there are two types of Crow schizophrenia: Type I (positive) and Type II (negative), although today this classification is not followed for diagnosis and is not reflected in the mental health reference manuals (DSM-5 and CIM -10), the reality is that Crow’s classification became the main reference at the time , let’s delve into the types of schizophrenia proposed by this psychiatrist and see how they differ:
It was given its name because positive symptoms predominate: hallucinations, delusions, positive thinking disorders (e. g. disorganization) and disorganized behavior.
On the other hand, the author compares this type of schizophrenia with the paranoid subtype, which would be found in the DSM-IV-TR (but more on the DSM-5).
The patient’s pre-morbid adjustment is good. In other words, the patient was more or less fit before the first symptoms of the disorder appeared.
The onset of type I schizophrenia is acute (compared to the onset of type II schizophrenia, which is insidious), which means that symptoms appear suddenly. Its evolution is acute, with epidemics and remissions. In schizophrenia II, on the other hand, the evolution is chronic and defective.
The prognosis for type I schizophrenia is reversible; Type II schizophrenia, on the other hand, is irreversible. This has, in large part, to do with the correct response to neuroleptics that people with schizophrenia I have and the wrong type II response.
Neuropsychological impairment in this type of schizophrenia is absent. With neuropsychological impairment, we mean possible deficits or changes in cognitive processes.
Cognitive symptoms (cognitive disorders) can be said to appear in some people with schizophrenia, as suggested by a Barrera et al study. (2006). According to the study, some of the most affected aspects are declarative memory, executive functions and sustained care.
At the pathological level, type I schizophrenia causes a number of neurochemical changes; Specifically, according to Crow, there is an increase in D2 dopamine receptors. Let us remember here that the neurotransmitter dopamine is heavily involved in schizophrenia (in particular, an excess of dopamine). In the case of type II schizophrenia, as we will see, the changes that occur are structural.
The second type of Crow schizophrenia, type II or negative, resembles the disorganized subtype of schizophrenia (DSM-IV-TR), due to the symptoms and characteristics of this subtype, so symptoms of schizophrenia type II are negative and include emotional flattening, poor language, and impulse loss.
Unlike the previous type, in type II schizophrenia, the pre-morbid setting is low; that is, the patient had changed operations before presenting the symptoms of the disorder.
The onset of type II schizophrenia is insidious (i. e. symptoms appear gradually), evolution is chronic and defective, and prognosis is irreversible; as we have seen above, the response to neuroleptics in type II schizophrenia is weak (bad).
Here, neuropsychological impairment is present and the affected individual may have deficits or changes in the cognitive area; Does this include memory, attention, executive functions?
At the brain level, structural changes occur; the result is a loss of cells in temporal lobe structures and parahypocampic convolution.
As we have seen, we could say that type I schizophrenia has the best prognosis because it is reversible and the response to neuroleptics is adequate, in terms of symptoms, type I is positive and type II is negative.
The presentation of type I is evident and its evolution is acute, unlike type II, in which the onset of symptoms is more subtle and its evolution is chronic.
To date, although no one is technically diagnosed with the type I or II schizophrenia label, it is true that the presentation of the disorder in each person may be more similar to any of the types proposed by Crow; however, it always seems risky to try. “Integrate” patients from a specific group: we know that each person has their own peculiarities (and even more so in mental health).
Timothy Crow was not the only author who tried to classify and group different types of schizophrenia, before he met the German psychiatrist Emil Kraepelin (1856–1926) and the Swiss psychiatrist Eugen Bleuler (1857–1939).
Kraepelin distinguished the following types of schizophrenia: paranoid, catatonic and hebephrenic (disorganized). Bleuler did the same classification as his colleague, but also added a new subtype: simple schizophrenia.