Many people have experienced a few nights of bad sleep that resulted in shifting attention spans, impulsive tendencies and hyperactivity the next day -- all behaviors resembling ADHD. A new study found that this dynamic may also be linked to increased entrepreneurial behavior...The results of the study published today in the journal Entrepreneurship Theory and Practice complement previous research that links sleep deprivation with lower productivity, lethargy and the hindrance of the longer-term success by suggesting that unhealthy sleep may have a limited upside.