Research Wonder: Heart Rate and Body Movement as Survey Quality Paradata?

What's a Research Wonder?  Read this to find out...

It seems inevitable - when many of us are wearing devices like smart watches and step counters that can also monitor our heart rate and even track movement while we sleep, when will that technology cross over into survey research?

It seems an obvious fit.  Imagine a survey of sexual assault victims where it is known that questions about certain topics could be disturbing to those who were victimized.  What if we monitored heart rate during the survey, and if we detected a spike in heart rate, we checked in with the respondent?  Is there a reason for the increased cardio-pump?  Are they now running while taking the survey?  Could it be that the questions are causing stress?  If that is the case, we could switch topics, or offer to "come back later".     

I WONDER...

Could the capture of movement and/or heart rate during a survey provide additional data that could play a role in logic/branching of the questionnaire or in the interpretation of the data? 

AND I WONDER...

Could we use heart rate increases during sensitive questions when the respondent skips a question as a proxy for a substantive response?  

AND I ALSO WONDER...

Would respondents agree to be monitored in such a way to begin with during a self-administered survey that they may be doing in the privacy of their own home?