526 OF THE NEKVOUS SYSTEM AND ITS ACTIONS. 



Intelligence and Will are no more concerned in the one case than in the 

 other. And hence it follows, that all the movements which are per- 

 formed by the instrumentality of the Cerebro-spinal system of ganglia 

 and nerves, are in their essential nature automatic ; and that their cha- 

 racter as Reflex, Instinctive, Emotional, or Voluntary, is entirely 

 dependent on the nature and seat of the impulses which respectively 

 originate them. 



924. There are various conditions, some of them natural, others 

 morbid, in which the distinctness of the functions of the Cerebral Hemi- 

 spheres is well marked. Thus in profound Sleep, they seem to be 

 entirely dormant ; the Spinal Cord and Medulla Oblongata, by which 

 the necessary reflex actions are carried on, being alone in a state of 

 activity. In this condition, the Sensory ganglia also appear to be in a 

 torpid state ; but in less profound sleep, actions are often performed, 

 which may be referred to the consensual group, being such as the sen- 

 sation would immediately prompt, without any reflection, and not being 

 remembered in the waking state. Thus we turn in our beds, under the 

 influence of an uneasy sensation ; or we give some sign of recognition 

 when our names are called. The first of these appears to be a purely 

 consensual movement, being as automatic as if it were a reflex action ; 

 the other seems to have become as automatic, by the influence of habit, 

 and to belong to that class of secondarily automatic actions, in which 

 the movement, though at first directed by the will, has become, after 

 very frequent performance, so closely associated with the guiding sug- 

 gestion, as to be called forth by it alone ( 904). In the Coma of Apo- 

 plexy, Narcotic Poisoning, &c., we witness the same gradations as in 

 ordinary sleep. When it is least profound, it seems to affect the Cere- 

 bral hemispheres alone ; the Sensory Ganglia being still, in some degree, 

 open to the reception of impressions. When complete, however, none 

 but reflex actions can be excited ; and if it advance to a fatal termina- 

 tion, it does so by the supervention of the same state of torpidity in the 

 Medulla Oblongata, whereby the respiratory movements are brought to 

 a close. These movements do not cease until the power of deglutition 

 has been lost, and until the eye ceases to close, when the edge of the 

 lid is irritated ; but when this is the case, a fatal termination may be 

 apprehended, as it is thus shown that the torpor is extending to the 

 Spinal system of nerves. In the condition of Dreaming, it would seem 

 as if the Cerebrum were partially active ; a train of thought being sug- 

 gested, frequently by sensations from without ; which is carried on with- 

 out any controlling or directing power on the part of the Mind ; and 

 which is not corrected, or is only modified in a limited degree, by the 

 knowledge acquired by experience. This condition is still more remark- 

 able in Somnambulism, or (as it has been better termed) Sleep-waking ; 

 in which the dreams are not only acted, but may be often acted on with 

 the utmost facility, a suggestion conveyed through any of the senses 

 excepting sight (which is usually in abeyance) being apprehended and 

 followed-up with the utmost readiness, and, in like manner, with little 

 or no correction from experience. Between this condition, and that of 

 ordinary dreaming, on the one hand, and that of complete insensibility 

 on the other, there is every shade of variety ; which is presented 



