the factors are : ( i ) the patient 's expectations of the experience of going to sleep and his/her belief that he can or can not control the onset of sleep , ( ii ) the patients ' personal theory of the cause of the problem , ( iii ) what the patient says to himself privately about the problem , ( iv ) the presence of stimuli in the sleep setting which arouse the patients including objects , persons and behavioural rituals .
C0037313
sleep
C0004927
behavioural