One of the biggest challenges in understanding the considerable variability of neurobehavioral outcomes of prenatal alcohol exposure involves identifying the dose and pattern of alcohol consumption as well as developmental timing of exposure. In general, the amount of alcohol consumed is correlated with the severity of outcome (e.g., Sood et al., 2001; Streissguth, Sampson, & Barr, 1989). However, pattern of alcohol exposure can often moderate these effects, with binge-like exposures resulting in more severe deficits than chronic exposure (Bailey et al., 2004; Bonthius, Goodlett, & West, 1988). Timing of exposure is also important. Alcohol exposure during different periods of fetal development can greatly influence the pattern and severity of structural and functional abnormalities (Guerri, Bazinet, & Riley, 2009). Unfortunately, this level of detail is often difficult to document, particularly in retrospectively recruited samples, and individual studies provide varying degrees of detail concerning levels and patterns of exposure. However, although criteria used to delineate heavy prenatal alcohol exposure may be inconsistent across studies, these samples generally include children of women who meet criteria for alcohol abuse and dependence (e.g., Coles et
