Sentence:  In view of the important role which emotional disturbances play in the genesis of neurotic and psychotic disorders and the parallelism observed between autonomic states and psychological behavior in several instances , it is <WSD>further</WSD> suggested that a hypothalamic imbalance may play an important role in initiating mental changes . 
Meaning of the word marked with <WSD> tags:  to or at a greater extent or degree or a more advanced stage (`further' is used more often than `farther' in this abstract sense)