Disorganized Thinking (Formal Thought Disorder)
Difficulty following a train of thought is called "disorganized thinking" or "formal thought disorder," which encompasses multiple specific subtypes including loosening of associations, circumstantial thinking, tangentiality, and derailment. 1
Specific Terminology and Subtypes
The term "disorganized thinking" is the broad clinical descriptor used in modern diagnostic frameworks, but several specific patterns exist 2:
- Loosening of associations: Ideas shift from one subject to another with unclear connections between thoughts 2, 3
- Circumstantial thinking: Excessive, unnecessary detail before reaching the point, though the goal is eventually reached 2
- Tangentiality: Responses that veer off-topic and never return to the original point
- Derailment: Sudden shifts between unrelated topics 3
- Flight of ideas: Rapid shifting between loosely connected thoughts, typically seen in mania 2
- Blocking: Sudden interruption in the train of thought 2, 4
- Incoherence: Severe disorganization where speech becomes incomprehensible 2
Clinical Context and Assessment
In humans, disorganization of thought is determined based on established norms for how an organized train of thought should progress. 1 This assessment requires clinical judgment to distinguish pathological thought patterns from normal variations in communication style.
Key Assessment Considerations
- Rule out confounding factors: Disorganized thinking must be distinguished from aphasia, parkinsonism (which can mimic thought blocking), delirium, and altered consciousness 2
- Context matters: These symptoms are characteristic of functional mental disorders (schizophrenia, bipolar disorder) but can also occur in dementia, delirium, and drug-induced states in elderly patients 2
- Multidimensional construct: Formal thought disorder comprises at least 5 dimensions: disorganization, verbosity, poverty of speech, idiosyncratic thinking, and blocking 4
Clinical Significance
Disorganized thinking is a core feature of psychotic disorders but is not specific to schizophrenia alone. 4, 3 The severity and persistence of thought disorder, particularly at the 0.50 and 0.75 severity levels on standardized scales, represents stable phenomena that may have predictive value 5. Idiosyncratic verbalization specifically shows stability over time and may be clinically significant even when not representing the most severe type of disturbance 5.
Relationship to Other Symptoms
Disorganized thinking shows moderate associations with impaired social cognition (r = -0.313), particularly affecting theory of mind (r = -0.349) and emotion recognition (r = -0.334) 6. These associations are largely independent of attentional disturbances and mania severity, suggesting disorganized thinking represents a distinct cognitive phenomenon 4.