In pursuing the discussion of alcohol effects in the CNS, it is helpful to define our terms and to examine precisely what is meant by “low dose alcohol”. In this review, we will define “low dose” effects as those seen when blood alcohol concentrations (BACs) are between 220mM EtOH, while recognizing that this spans a wide range of behavioral effects in humans and the relationship between behavioral intoxication and measurement of BACs is complicated[2]. Very low alcohol levels (1–2mM) produce zero or undetectable effects, in all but alcohol-naïve individuals. Slightly higher levels, associated with minimal social drinking (5–10mM) produce detectable effects on visual acuity, are anxiolytic and elicit signs of modest behavioral disinhibition, while higher levels of blood alcohol (15–20mM) typically produce a degree of sedation and motor incoordination that is considered incompatible with operation of a motor vehicle [and which is illegal in many countries]. We will nevertheless define all of these effects as being within the low dose range (L).
