NATURE 



497 



THURSDAY, SEPTEMBER 21, 1S82 



PSYCHOLOGICAL DEVELOPMENT IN 

 CHILDREN 

 Die Seele des Kindes, Beobcuktttngen uber die geistige 

 Entwiekelung des Menschen in den ersten Lebensjahren. 

 Von W. Preyer, ordentlichem Professor der Physiologie 

 an der Universitat und Director des physiologischen 

 Instituts zu Jena, etc. (Leipzig: Th. Grieben, 18S2.) 



THIS is a large octavo volume, extending to over 400 

 pages, and consisting of daily observations without 

 intermission of the psychological development of the 

 author's son from the time of birth to the end of the first 

 year, and of subsequent observations less continuous up 

 to the age of three years. Prof. Preyer's name is a suffi- 

 cient guarantee of the closeness and accuracy of any 

 series of observations undertaken with so much earnest- 

 ness and labour, but still we may remark at the outset 

 that any anticipation which the reader may form on this 

 point will be more than justified by his perusal of the 

 book. We shall proceed to give a sketch of the results 

 which strike us as most important, although we cannot 

 pretend to render within the limits of a few columns 

 any adequate epitome of so large a body of facts and 

 deductions. 



The work is divided into three parts, of which the first 

 deals with the development of the Senses, the second 

 with the development of the Will, and the third with the 

 development of the Understanding. 



Beginning with the sense of Sight, the observations 

 show that light is perceived within five minutes after 

 birth, and that the pupils react within the first hour. On 

 the second day the eyes are closed upon the approach of 

 a flame ; on the 1 ith the child seemed to enjoy the sen- 

 sation of light ; and on the 23rd to appreciate the rose 

 colour of a curtain by smiling at it. Definite proof of 

 colour discrimination was first obtained in the 85th week, 

 but may, of course, have been present earlier. When 

 770 days old the child could point to the colours yellow, 

 red, green, and blue, upon these being named. 



The eyelids are first closed to protect the eyes from the 

 sudden approach of a threatening body in the 7th or 8th 

 week, although, as already observed, they will close 

 against a strong light as early as the second day. The 

 explanation of their beginning to close against the 

 approach of a threatening body is supposed to be that an 

 uncomfortable sensation is produced by the sudden and 

 unexpected appearance, which causes the lids to close 

 without the child having any idea of danger to its eyes ; 

 and the effect is not produced earlier in lite because the 

 eyes do not then see sufficiently well. On the 25th day 

 the child first definitely noticed its father's face ; when 

 he nodded or spoke in a deep voice, the child blinked. 

 This Prof. Preyer calls a " surprise-reflex" ; but definite 

 astonishment (at the rapid opening and closing of a fan) 

 was not observed till the 7th month. The gaze was first 

 fixed on a stationary light on the 6th day, and the head 

 was first moved after a moving light on the nth day ; on 

 the 23rd day the eyeballs were first moved after a moving 

 object without rotation of the head ; and on the Sist day 

 objects were first sought by the eyes. Up to this date 

 the motion of the moving object must be slow if it is to 

 Vol. xxvi. — No. 673 



be followed by the eyes, but on the 101st day a pendulum 

 swinging forty times a minute was followed. In the 31st 

 week the child looked after fallen objects, and in the 47th 

 purposely threw objects down and looked after them. 

 Knowledge of weight appeared to be attained in the 43rd 

 week. Persons were first distinguished as friends or 

 strangers in the 6th month, photographs of persons were 

 first recognised in the ioSth week, and all glass bottles 

 were classified as belonging to the same genus as the 

 feeding-bottle in the Sth month. 



With regard to the sense of Hearing, it is first remarked 

 that all children for some time after birth are completely 

 deaf, and it was not till the middle of the 4th day that 

 Prof. Preyer obtained any evidence of hearing in his child. 

 This child first turned his head in the direction of a sound 

 in the 11th week, and this movement in the 1 6th week 

 had become as rapid and certain as a reflex. At 8 months, 

 or a year before its first attempts at speaking, the infant 

 distinguished between a tone and a noise, as shown by its 

 pleasure on hearing the sounds of a piano ; after the first 

 year the child found satisfaction in itself striking the 

 piano. In the 21st month it danced to music, and in the 

 24th imitated song ; but it is stated on the authority of 

 other observers that some children have been able to sing 

 pitch correctly, and even a melody, as early as 9 months. 

 One such child used at this age to sing in its sleep, and 

 at 19 months could beat time correctly with its hand while 

 singing an air. 



Concerning Touch, Taste, and Smell, there is not so 

 much to quote, though it appears that at birth the sense 

 of taste is best developed, and that the infant then re- 

 cognises the difference between sweet, salt, sour, and 

 bitter. Likewise, passing over a number of observations 

 on the feelings of hunger, thirst, satisfaction, &c, we 

 come to the emotions. Fear was first shown in the 14th 

 week ; the child had an instinctive dread of thunder, and 

 later on of cats and dogs, of falling from a height, &c. 

 The date at which affection and sympathy first showed 

 themselves does not appear to have been noted, though 

 at 27 months the child cried on seeing some paper figures 

 of men being cut with a pair of scissors. 



In the second part of the book it is remarked that 

 voluntary movements are preceded, not only by reflex, 

 but also by "impulsive movements"; the ceaseless 

 activity of young infants being due to purposeless dis- 

 charges of nervous energy. Reflex movements are fol- 

 lowed by instinctive, and these by voluntary. The latter 

 are first shown by grasping at objects, which took place 

 in Preyer's child during the 19th week. The opposition 

 of the thumb to the fingers, which in the ape is acquired 

 during the first week, is very slowly acquired in the child, 

 while, of course, the opposition of the great toe is never 

 acquired at all ; in Preyer's child the thumb was first 

 opposed to the fingers on the 84th day. Up to the 17th 

 month there is great uncertainty in finding the mouth 

 with anything held in the hand — a spoon, for instance, 

 striking the cheeks, chin, or nose, instead of at once 

 going between the lips ; this forms a striking contrast to 

 the case of young chickens which are able to peck grains, 

 &c, soon after they are hatched. Sucking is not a pure 

 reflex, because a satisfied child will not su:k when its lips 

 are properly stimulated, and further, the action may be 

 originated centrally, as in a sleeping suckling. At a later 



