Science / Psychiatry / Incoherence: Speech or thinking that is essentially incomprehensible to others because words or phrases are joined together without a logical or meaningful connection. This disturbance occurs within clauses, in contrast to derailment, in which the disturbance is between clauses. This has sometimes been referred to as word salad to convey the degree of linguistic disorganization. Mildly ungrammatical constructions or idiomatic usages characteristic of particular regional or cultural backgrounds, lack of education, or low intelligence should not be considered incoherence. The term is generally not applied when there is evidence that the disturbance in speech is due to an aphasia.
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