Mean percentage of head-turning toward the sound for cocaine-exposed and control neonates during: familiarization phase quartile blocks (panel a); novelty phase trial blocks (panel b); and the dishabituation phase trial block (panel c).
Classification of Cocaine Users by Quantity and Frequency of Use*
n of 25
Percentage of users
* Cocaine use was divided into 4 categories as follows: light, cocaine use limited to the first trimester, <.5 g, less than once per week; moderate, use throughout gestation, 0.5 g or less between 1 and 3 times per week; heavy, use throughout gestation, .25–1 g daily; very heavy, use throughout gestation, more than 1 g daily. For 3 mothers who failed to complete the questionnaire, the extent of cocaine use was estimated from social work records.
Number of Cocaine-Using and Control Mothers Who Used Other Substances