It is called disorganized thinking, this allows a person exhibit a disturbance in the way she acts, responds or thinks. It could make a person respond unclearly, the person can't focus on a particular thing that made her fail to concentrate to things. It could be seen above as Claire exhibits these symptoms, making her positive to have a disorganized thinking.
Any particular time? I guess the most relevant time for this question is early half of 20th century.
I think the event was first world war and some of its consequences (in many countries the monarchy was abolished so people "experimented" with new political organisatons, in Germany the war brought huge reparations which contributed to the deterioration of their economy)
and the global economic crisis of 1920
The state of being excluded from social activity as an 'outsider'
