Millisecond Forums

If this is my code where target word and rectangle surrounding it appears at 200 ms and rectangle disappears after 300 ms whereas target remains on the screen  and a subject has to respond before rectangle disappears.
Then my question is - the latency recored by software, is it the response time from 200 ms ( when target appeared for the first time ) or is it the response time from the last fame which is 300 when the target reappears again ( although it is not evident to naked eye)