Experimental Psychology. — ''The Psychology of Conditions of 

 Confusion'. B3 Prof. E. D. Wikksma. 



(Communicated in the meeting of April 26, 1918). 



The contents of our consciousness distinguish tliemselves by 

 their intensity. When altentiveness is directed on them they have a 

 higli grade of consciousness. When our altention is scattered over 

 many psj'chical contents or there is a weakening or depression of 

 the attentivoness, we speak of a generally low grade of consciousness, 

 by which we have to understand a condition in which external 

 imi)ressions or also our own thoughts can not, or with difficulty, 

 cross the threshold of consciousness; in which associations do not, 

 or incompletely, come to pass; in which the formation of syntheses 

 is hampered, in other words, a condition in which the precision, 

 the clearness ami the velocity of conception of the contents of 

 consciousness is diminished. Such depressions of consciousness occur 

 in many forms, normally as well as pathologically. The momentary 

 weakenings of consciousness cause normally the phenomena of 

 depersonalisatiou and of "fausse i-econnaissance", as was proved l)y 

 the investigations of Heymans, and pathologically the epileptic fits 

 as the psychology of epilepsy teaches us. 



More prolonged depressions occur normally in dullness, exhaustion, 

 sleepiness, and sleep, and pathologically in the conditions of acute 

 confusion as we meet them in or after acute infectious diseases, in 

 some intoxications, and sometimes in meningitis. 



These processes can make their appearance in many different 

 forms. At one time the stupor is more pronounced, then again the 

 confusion and desorientation, strong disturbances of memory, hallu- 

 cinations, delusions, and motor restlessness. In whatever form the 

 disease presents itself the characteristics of a lowered grade of 

 consciousness are always clearly present. The constant presence of 

 this one syujptom with the great change in all other phenomena, 

 makes it probable that the former is primary to those other symptoms. 

 This opinion is strengthened by the fact that all the symptoms of 

 confusion disappear for a moment if we are able to obviate or 

 lessen the intensity of the depression of attentiveness. In a raving 

 fever patient, in a patient with delirium tremens, with uraemia or 



