PSYCHONEUROSIS 



6382 



PTARMIGAN 



energises a specific kind of active 

 response (e,g. flight). The character 

 of the emotion is practically per- 

 manent, but the objects which 

 stimulate it and the actions to 

 which it leads may vary enor- 

 mously from the simple types we 

 see in the animal world. For 

 example, the object feared may be 

 an infectious disease, and the de- 

 fensive action an elaborate process 

 of inoculation. There is in man a 

 further tendency of the instincts 

 to yield complex systems of emo- 

 tions and desires having permanent 

 and often ideal objects. These 

 systems are described by A. F. 

 Shand as sentiments. A man's own 

 self, his family, his business, his 

 country, are instances of objects 

 towards which sentiments are de- 

 veloped, and the nature of his 

 emotional reactions towards them 

 largely determines what we call 

 his character. 



Hypnotism and Personality 

 The simple observation that we 

 are, at a given moment, conscious 

 only of a minute fraction of the 

 memories we carry in our minds 

 suggested long ago the idea that 

 there are unconscious mental 

 phenomena. The study of hypnot- 

 ism and of " alternating person- 

 ality " has done much to increase 

 the significance of this idea, while 

 the discoveries of Freud and his 

 followers have shown that the 

 influences of the unconscious layers 

 of the mind constantly affect our 

 behaviour, often in the most im- 

 portant way. The results of 

 Freud's work are, indeed, likely 

 to have epoch-making significance 

 in medicine, criminology, and 

 education. 



" Behaviourism " has grown 

 partly out of experimental human 

 psychology, partly out of animal 

 psychology. A typical experiment 

 in human psychology is to exhibit 

 to a person a signal (e.g. a word), 

 and to measure the time he takes 

 to respond to it by a prearranged 

 act, e.g. pressing an electric key. 

 A typical investigation in animal 

 psychology is to put a hungry rat 

 repeatedly into a maze and to 

 observe how he learns to take the 

 direct route to the food placed at 

 the exit. In both cases the psycho- 

 logist is not the agent who ex- 

 periences the activity, but a by- 

 stander who arranges the experi- 

 ment and records what happens. 

 The rapid growth of interest hi 

 behaviourism is largely due to the 

 fact that many highly promising 

 applications of psychology depend 

 upon observations essentially of 

 this kind. For example, tests of 

 general ability and of fitness for 

 special vocations, inquiries into 

 industrial fatigue, and the best 



ways of carrying out skilled opera- 

 tions may all be regarded as appli- 

 cations of the method of be 

 haviourist psychology. 



Bibliography. Principles of 



Psychology, 2 vols., W. James, 

 1901 ; Psychology from the Stand- 

 point of Behaviorism, J. B. Wat- 

 son, 1919 ; Social Psychology, W. 

 McDougall, new ed. 1919 ; Mind 

 and Work, C. S. Myers, 1920; 

 Foundations of Character, A. F. 

 Shand, new ed. 1920 ; Psycho- 

 logical Principles, J. Ward, 2nd ed. 

 1920; An Introduction to Psycho- 

 logy, S. S. Brierley, 1921; The 

 Psychology of Everyday Life, J. 

 Drever, 1921. 



Psychoneurosis. Mental dis- 

 order, the result of a chain of ab- 

 normal psychological processes. See 

 Hysteria ; Neurasthenia ; Neurosis. 

 Psychophysics (Gr. psyche, 

 soul, mind ; pkysika, physics). 

 Term inventeu by the German 

 philosopher 

 Fechner, and de- 

 fined by him as 

 an exact theory 

 of the relations 

 between mind 

 and body, and, 

 generally speak- 

 ing, the rela- 

 tions between 

 the psychical 

 and physical 



worlds. According to Wundt, it 

 consists in the investigation of 

 the relations that can be shown 

 empirically to exist between the 

 psychical and physical aspects of 

 vital processes. The object is to 

 discover these relations ; beyond 

 that its interest ceases. Psychology, 

 on the other hand, examines these 

 relations from the point of view of 

 the mind ; physiology, from the 

 point of view of the body. 



Psychosis. Disorder of the 

 mind, not due to recognizable 

 psychological processes as are the 

 neuroses and psychoneuroses. The 

 term is practically equivalent to 

 insanity (q.v.). 



Psychotherapy (Gr. psyche, 

 soul ; therapeia, treatment). Treat- 

 ment of mental disorders by in- 

 fluencing the mind. Usually em- 

 ployed for the treatment of hys- 

 teria, neurasthenia, and kindred 

 affections, it embraces treatment 

 by suggestion, hypnotism, psycho- 

 analysis, and various forms of re- 

 education where function has been 

 impaired without organic disease. 

 Psychrometer (Gr. psychros, 

 cold ; metron, measure). Name 

 given to a wet and dry bulb ther- 

 mometer. It consists of two ther- 

 mometers, one with a bulb ex- 

 posed to the air, and the other with 

 the bulb covered with muslin kept 

 wet with water. The first gives the 

 direct air temperature ; the second 



a lower temperature due to the 

 evaporation of the water. The 

 drier the atmosphere the more 

 rapid the evaporation, and the 

 greater the difference of temper- 

 atures recorded by the two ther- 

 mometers, so enabling the amount 

 of moisture in the atmosphere to 

 be calculated. 



Ptah. Egyptian deity. The 

 local god of Memphis in the 1st 

 dynasty, he was the divine artificer, 

 creating all things out of the Nile 

 mud. Assimilated to other gods 

 Osiris, Apis, Sokar he is repre- 

 sented with a mummified body, 

 wearing a skull-cap. In later times, 

 as a bandy-legged dwarf, he 

 resembled the Greek Hephaestus. 

 See Egypt. 



Ptarmigan (Gaelic larmachan). 

 Species of grouse (Lagopus midus), 

 found in the mountainous districts 

 of N. Europe. In summer the 

 plumage is 

 brownish grey 

 marked with 

 black lines and 

 dark spots, and 



Ptarmigan. Species of grouse found 



in the Scottish highlands. Top. 



left, hen bird ; below, cock 



W. S. Btrridgt. F.Z.S. 



in winter it is white with the ex- 

 ception of a small scarlet comb, 

 a black line on each side of the 

 head, and black outer tail feathers. 

 It is the only British bird that thus 

 changes its plumage for protective 

 purposes. It is 14 ins. long, and the 

 legs and feet are thickly feathered. 

 In Great Britain it is restricted to 

 the highest parts of the Scottish 

 highlands and to some of the west- 

 ern islands. Both in summer and 

 whiter it so closely resembles its 

 surroundings that it is difficult to 

 detect until it takes flight. In the 

 nesting season the hen sits so close 

 that she may be approached with- 

 out difficulty, and when the young 

 are about, the hen will endeavour to 

 draw off an intruder by running 



