In this sentence,it could be explained like that(While S V)in English.But accurately speaking,it means during the time when I'm not aware of in Chines(grammatically).But you could understand it like that (While S V). In general, 在~中 has several explanations.It could refer to a limit of location,time,range and so forth.Well,it depends. For instance, 在家中 means at home(a limit of location) 在上班中 means at work/at the time of working Hope this won't make you feel confused.