Flight of Ideas
A nearly continuous flow of accelerated speech with abrupt changes from topic to topic that are usually based on understandable associations, distracting stimuli, or plays on words. When severe, speech may be disorganized and incoherent. It is part of the DSM -5 criteria for Manic episode.
The spontaneous speech of the patient is usually increased and he generally finds it difficult to stop talking. He may continue to talk or sing until he becomes hoarse or he may lose his voice entirely. He frequently shows a flight of ideas by moving rapidly from one subject to another. In contrast to the disconnected flight of ideas of the schizophrenic, the manic usually demonstrates some unifying theme underlying his tangential associations
DESCRIPTION IN FISH PSYCHOPATHOLOGY
The thoughts follow each other rapidly, there is no general direction of thinking and the connexions between successive thoughts appear to be due to chance factors which, however, can usually be understood. The patient’s speech is easily diverted to external stimuli and by internal superficial associations
DESCRIPTION IN THE ESSENTIALS OF POSTGRADUATE PSYCHIATRY
Flight of ideas is encountered in manic… and it can even appear in relatively pure form in some subjects, who on other criteria would be considered undoubtedly schizophrenic. There is an accelerated tempo of speech often referred to as pressure of talk. In addition to the increased rate of delivery, the language employed is characterised by a wealth of associations, many of which seem to be evoked by more or less accidental connections… the excited speech wanders off the point following the arbitrary connections, and the coherent progress of ideas tends to become obscured… In flight of ideas, a wide range of unusual connections drive on the rapid speech and listener is often borne along by the flow.
Beck A. Depression. University of Pennsylvania Press, 1972.