[Note. - The words and phrases here included fall under three main heads: -

(i) Words in common philosophical or medical use, to which no new shade of meaning is given in this inquiry, eg. ecmnesia. Introducing a few of these words for the ordinary reader's convenience, I have generally taken the definition from Hack Tuke's Dictionary of Psychological Medicine (London: Churchill, 1892), which is the most authoritative - almost the only - English work of its kind.

(2) Words or phrases in themselves not new, but used in psychical research with some special significance; - as, for instance, "systematised anaesthesia," "negative hallucination." These two phrases are constantly used by writers on hypnotism: but mere familiarity with the words themselves would not explain their meaning in that context to a reader fresh to hypnotic discussions.

(3) A few words, distinguished by an asterisk, for which I am myself responsible. I must leave it to my readers to judge how far these words are likely to be useful. But I would suggest that when a subject so novel as ours is made the subject of discussion in many countries, there is a convenience in using words of Greek or Latin derivation, which can be adapted to all languages, and can be made to bear a clearly defined signification].

Aboulia

Loss of power of willing. I have used the word hyperboulia to express that increased power over the organism, resembling the power which we call will when it is exercised over the voluntary muscles, which is seen in the bodily changes effected by self-suggestion.

After-Image

The picture of an object seen after removing the gaze from the object. It is called positive when it reproduces, negative when it reverses the true illumination or colours of the actual object. After-images are regarded as retinal or entoptic, belonging to the interior of the eye. After-images must be distinguished from memory-images, which may appear spontaneously, or may be summoned by an effort of will, long after the original sight of the object.

Agent

The person on whose condition a telepathic impression seems to be dependent; who seems to initiate the telepathic transmission.

Agraphia

See Aphasia.

Alexia

See Aphasia.

Alternation Of Personality

See Disintegration of personality.

Anasthesia

Anasthesia, or the loss of sensation generally, must be distinguished from analgesia, or the loss of the sense of pain alone. Many hypnotic subjects are analgesic but not anaesthetic. Systematised anesthesia or negative hallucination signifies the condition of an entranced subject who has been told (for instance) that Mr. A. is not in the room, while he is in reality present. The subject may thus be said to have a negative hallucination, or to have been deprived of a certain group or system of perceptions, in that he fails to see Mr. A. Other words descriptive of the general sensory condition are dysoesthesia, impaired or painful sensation; paroesthesia, erroneous or morbid sensation; hyperesthesia, unusually keen sensation, which may or may not be a morbid symptom. Hyperæsthesia may be peripheral, when it affects nerve-endings near the surface of the body, or central, when the excessive sensitiveness belongs to the central sensorium; - such parts, namely, of the brain as are concerned in receiving or generating sensory images and impressions. Hemi-anesthesia means anaesthesia of half the body, the median line (down the middle of the body) separating normal sensation from absence of sensation. Anaesthetic zones or patches (formerly deemed characteristic of witches) are common in hysteria.

Coenesthesia means that consensus or agreement of many organic sensations which is a fundamental element in our conception of personal identity. Finally, I have suggested the word *panoesthesia to express the undifferentiated sensory capacity of the supposed primal germ.

Analgesia

Insensibility to pain.

Aphasia

Incapacity of coherent utterance, not caused by structural impairment of the vocal organs, but by lesion of the cerebral centres for speech. Distinguished from congenital or acquired aphonia, due to paralysis or imperfect approximation of the vocal cords, and also from hysterical mutism, when the patient is obstinately and involuntarily silent, although the vocal organs are uninjured and the cerebral centres of speech are only functionally affected, with no visible lesion. All the four forms of verbalisation are subject to separate disorders of the type of aphasia. Lack of power to write words is called agraphia or agraphy; lack of power to understand words written, alexia or word-blindness; lack of power to understand words uttered, word-deafness. In each case the trouble may lie in the brain and not in the organ of sense or other organs. For instance, a man's sight even for printed musical notes may be unimpaired, while yet he is unable to understand printed words.

Aphonia

Incapacity of uttering sounds.

Attaque De Sommeil

This French term is more correct than the word "trance," to express those spontaneous lapses into prolonged and profound sleep which sometimes occur in hysterical subjects.