A temporary loss of judgment and higher reasoning capability that one may experience immediately after consumption of KFC's double-down sandwich. Initial symptoms may include confusion, euphoria, and slurred speech. These are soon followed by loss of physical coordination and language ability (several patients have been observed to repeatedly utter variations of the phrase "hurr herp derp"). Patients may then enter a trance-like state for prolonged, variable amounts of time. A full recovery is typical within a few hours to a few days, although in some cases lasting brain damage has been reported.
In the hospital, it was discovered that what psychiatrists initially believed to be severe mental retardation was nothing more than a case of Double Down Syndrome after a late lunch.