Different types of alcohol nystagmus.

In a series of earlier papers, (Aschan, Bergstedt, Goldberg, and Laurell 1955, 1956) positional alcohol nystagmus (PAN) appearing in two phases has been described, with special references to the relationship between PAN and the blood alcohol level. All details will be found in these publications. It should be mentioned here that in normal subjects the two phases of PAN were demonstrated at maximal blood alcohol concentrations as low as 0.02 per cent. This figure seems surprisingly low in comparison with the values reported by earlier authors, who consider that blood alcohol concentrations of 0.06 per cent or more are needed before alcohol nystagmus can be demonstrated clinically. Some of the forms of alcohol nystagmus described earlier have been observed under different conditions, in alcohol-intoxicated patients in a state of unconsciousness (Bernhard and Goldberg 1934), or with the patient looking in the lateral direction and with open eyes (Goldberg 1943). Positional nystagmus described by earlier auth...