Which of the following is not part of the Schneider classification of thought disorder: Desultory, Omission, Fusion, Driveling, or Over-inclusion?

Schneider Classification of Thought Disorder

Over-inclusion is not part of the Schneider classification of thought disorder. 1

Understanding Schneider's Classification

Carl Schneider described several formal thought disorders in schizophrenic patients, which include:

1. Derailment - A pattern of speech in which ideas slip off track onto another that is completely unrelated
2. Fusion - The merging of unrelated thoughts or concepts
3. Omission - Leaving out essential parts of thoughts or sentences
4. Driveling - Incoherent, meaningless speech that lacks logical connection
5. Desultory thinking - Jumping from one topic to another without logical connections 2, 1

Historical Context of Thought Disorder Classifications

The concept of formal thought disorders has deep historical roots in psychiatry:

• Early descriptions date back to the 19th century with Esquirol
• Emil Kraepelin described akataphasia (inability to find appropriate expression for a thought) in patients with dementia praecox (later termed schizophrenia)
• Bleuler and Kretschmer identified "loosening of associations" in schizophrenic patients
• Carl Schneider's classification specifically included derailment, fusion, omission, suspension and driveling 1

Prevalence of Schneider's Thought Disorders

Research has shown varying frequencies of these thought disorders in schizophrenic patients:

• Driveling: 67.9%
• Desultory thinking: 57.3%
• Loosening of association, gaps, derailment: 28.9% 2

Distinguishing Over-inclusion

Over-inclusion is a thought disorder characterized by an inability to preserve conceptual boundaries, where thinking becomes over-generalized and includes irrelevant elements. While it is a recognized thought disorder, it is not part of Schneider's original classification 1.

Over-inclusion is more commonly associated with other classification systems of thought disorders that were developed after Schneider's work, particularly in the context of broader neuropsychological assessments of schizophrenia and related disorders 3.

Clinical Implications

Understanding the correct classification of thought disorders is important for:

• Accurate diagnosis of schizophrenia and other psychotic disorders
• Proper assessment of symptom severity
• Development of appropriate treatment plans
• Research purposes in studying the phenomenology of psychotic disorders

The distinction between different types of thought disorders helps clinicians better characterize the specific cognitive impairments present in individual patients, which can guide more targeted therapeutic approaches.