CONSCIOUSNESS 203 



end, so that the time elapsing between the application 

 of a stimulus (say an electric shock lasting only one thou- 

 sandth of a second) and its recognition in awareness 

 ranges from one-tenth of a second to more than one sec- 

 ond. Even consciousness of a deliberate movement of the 

 hand or foot is equally removed in time from the motion 

 itself. The movement follows only after the interval re- 

 quired for the transmission of nerve impulses from the 

 motor cortex to the periphery, and since what is cus- 

 tomarily perceived is the contraction of muscles or 

 change of position of the hand or foot, the sensory im- 

 pulses recording the movement are further delayed by 

 transmission from the periphery back to the cortex. 



Both sensory and motor sequences are, however, given 

 the semblance of simultaneity by their fusion and per- 

 sistence in areas of the brain that are several steps re- 

 moved in nemologic level ( and in time ) from the initiat- 

 ing events themselves. It is this fusion and persistence 

 that give to consciousness its seeming continuity from 

 one moment to the next. 



Those things that dominate in consciousness are com- 

 monly said to occupy the 'center of attention,' but even 

 here the clarity and intensity of awareness vary from 

 moment to moment. Around the focus of attention is a 

 peripheral field functionally belonging to consciousness, 

 but not to immediate awareness; in this shadowy area 

 events may leave their mark in unconscious memory, to 

 be recalled only under hypnosis or in association with 

 special circumstances. This dim penumbra is the area 

 that the psychiatrist calls the 'unconscious [or subcon- 

 scious] mind.' These are meaningless words physiologi- 

 cally. We repeat Hume's definition of 'mind' as an ab- 

 stract term denoting the series of ideas, memories, and 

 feelings which appear in consciousness: it is meaningless 

 to think of an abstract term as being either unconscious' 

 or as 'subconscious.' These words represent a mistrans- 



