Illusion as a Symptom of Insanity

Illusion is a false, exaggerated, or perverted perception of something which is really appreciated by the senses; for example, the patient, seeing a small object moving across the floor, may think it to be a mouse or a reptile, having an illusion of sight. A person suffering with illusion of the sense of hearing, may pervert the gentle patter of rain into a conversation held between two persons in a neighboring room. The sense of touch, taste, smell, etc., may all be subject to illusion. This is not by any means a positive symptom of insanity, as the best of us are subject to illusion at times, and it has been very sagaciously suggested that it is nothing more than probable that we never appreciate objects exactly as they are, that our senses never inform us with absolute correctness, perhaps, of the objects with which we come in contact. This accounts for the difference in individual judgments in some matters, and in the judgment of the same individual at different times.

Hallucination as a Symptom of Insanity

This is a false perception which has no foundation whatever, originating entirely within the brain. The perception is wholly imaginary, and not, as in the case of illusion, a simple perversion of a real perception. A person affected with hallucination sees pictures and images upon a blank wall. He imagines himself surrounded by various persons or objects when he is quite alone. A very curious fact is that persons who may be absolutely deprived of any of the senses may suffer with hallucinations of the lost sense; as, for instance, a woman who had been totally deaf for years, being unable to perceive the loudest noises, not noticing even the firing of a cannon, when suffering with hallucination, was constantly troubled with voices whispering in her ears.

Delusion as a Symptom of Insanity

A person may suffer with both hallucinations and illusions and yet be perfectly aware of the imaginary character of his perceptions; but when the mind is so affected that hallucinations and illusions are considered as realities, the individual is subject to delusion. Although delusion is a much more serious mental derangement than either illusion or hallucination, it is by no means a positive test of insanity, as it has often been considered to be, by both legal and medical authors. As a recent writer remarks, if delusion were a test for insanity, "one-half of the world would be trying to put the other half into lunatic asylums."

Incoherence as a Symptom of Insanity

An individual is incoherent when he puts words together without proper relation to each other, so that they do not make sense.

Delirium as a Symptom of Insanity

Delirium is a condition of the mind in which all the previously mentioned symptoms are present, together with inability to sleep, active pulse, and great restlessness. It is very common in acute fevers.

Mental disease assumes a very great variety of forms, according to the different portions of the brain affected or the different faculties involved. We shall not attempt to go into an elaborate consideration of the subject, however, but will briefly call attention to some of the most common forms of the disease, which are termed mania, melancholia, and dementia.