Introduction, diagnostic features and symptoms of Schizophrenia

The word schizophrenia means splitting of the mind. It is a serious psychiatric disorder. This disorder is first described by Emil Kraeplin. He called it  dementia praecox and he believed it to be having a relationship with dementia. But later  Eugen Bleuler and  Kurt Schneider classified it into a separate mental illness that does not have a direct relationship with dementia.

This disorder is characterized by delusions, hallucinations and disorder of thinking. Delusions are false illogical beliefs that does not have social, or cultural explanations. e.g. Martians are controlling my thoughts.

Hallucinations are perceptual equivalent of delusions. They are abnormal perceptions without stimulus. It can be experienced as voices without there being a person speaking or seeing things without an external object. For the patient, hallucinations are equivalent to normal perceptions. He/she cannot differentiate between normal and abnormal perceptions. Hallucinations must be differentiated from illusions. Illusions are distortion of normal perception. e.g. seeing wires as snakes. Unlike hallucinations, illusions goes away once the attention is focused onto the perception. Illusions can occur in normal people and they have no diagnostic significance.

But hallucinations and delusions occur in many mental disorders such as depression, bipolar disorder, delusional disorder and delirium. Therefore, to diagnose schizophrenia doctors developed a set of diagnostic criteria. These criteria include specific hallucinations, delusions and other symptoms that are seen only in schizophrenia. The two main diagnostic criteria are ICD - 10 that was developed by WHO and DSM IV developed by American Psychiatry association.

What are the most common symptoms seen in schizophrenia?

Symptoms of schizophrenia can be classified as positive symptoms and negative symptoms. Positive symptoms are delusions, hallucinations and interference with thinking.

Negative symptoms are usually seen in people with long standing schizophrenia. Common negative symptoms seen in patients with chronic schizophrenia are,

1.       Apathy

2.       Lack of drive

3.       Slowness

4.       Social withdrawal

5.       Underactivity

6.       Depression

In addition, schizophrenic patients show problems in thought process. These patients show sudden withdrawal or blocking of thoughts, interpolation of several thoughts and improper addition of new thoughts. These processes result in incomprehensible speech or irrelevant speech.

Characteristic sign seen by other is loosening of associations. Here speech jumps from one topic to another without any identifiable reason. It is also called knights move thinking.

According to the ICD 10 Criteria schizophrenia can be diagnosed when at least one of the following symptom is present for more than one month duration

1.       Third person Auditory hallucinations : Hearing several people talking to the patient, referring him in third person (e.g. He , She)

2.       Thought echo : – Patients own thoughts spoken aloud (Hallucination)

3.       Thought insertion : – Insertion of thoughts into the head (Delusion)

4.       Thought withdrawal :- Removal of thoughts by an outside agency (Delusion)

5.       Delusions of control: – Persons actions are controlled by an outside agency.

6.       Delusional perception: – Attaching abnormal meaning to a normal perception.

7.       Hallucinatory voices giving running commentary of the patients actions 

8.       Breaks and interpolations of thought giving rise to incoherent and irrelevant speech.  

9.       Persistent negative features mentioned above

10.   Significant functional impairment in day to day activities.