20885
A crucial question is whether deficits in this circuit persist after drug cessation , and whether recovery of this system will be seen after extended periods of abstinence , a question with implications for treatment course and outcome .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None