These studies were not unchallenged, and some investigators reported finding the opposite – that FHN were more responsive to alcohol [e.g. (McCaul et al. 1990)]. David Newlin surveyed this literature and attempted to explain this contradiction (Newlin, Thomson 1990). In essence, what he found was that the differences that the Schuckit group described generally occurred beginning around one hour after ingestion, when individuals were at the peak or on the descending arm of the blood alcohol curve. Those who found FHN individuals to be more responsive to alcohol tended to find changes earlier after ingestion. The overall suggestion of this analysis was that FHP individuals may really differ most in the development of acute functional tolerance. Because they develop more tolerance, and more quickly, they look less affected than FHN an hour or so after ingestion. Acute functional tolerance was first documented by Mellanby (1919), who placed dogs on a treadmill and slowly infused alcohol intravenously, leading to first rising and then falling blood alcohol levels (BAL). He noted that they stumbled more when BAL was rising than they did
