Substance use is prevalent among adolescents in the U.S., especially males.
View Article and Find Full Text PDFPurpose: Both substance use and depression are common in adolescence and often comorbid. Past research has produced conflicting results on whether there is a temporal relationship, and if so, in which direction it operates and how it may vary by sex. We examined the longitudinal associations between substance use frequency and depressive symptoms from adolescence into young adulthood and whether the associations were moderated by sex.
View Article and Find Full Text PDFPurpose: Both substance use and depression are common in adolescence and often comorbid. Past research has produced conflicting results on whether there is a temporal relationship and if so, in which direction it operates and how it may vary by sex. The purpose of this paper is to explore the longitudinal, potentially bidirectional, relationships between high-frequency substance use and depressive symptoms from adolescence into young adulthood for males and females.
View Article and Find Full Text PDFDespite the evidence that there is a daily rhythm in smoking behavior and that the effects of drugs of abuse exhibit diurnal variations, very few studies have explored the extent to which sensitivity to the effects of nicotine vary over the course of the day. In the studies described in this report, the melatonin proficient mouse strain C3H/Ibg and the melatonin deficient mouse strains C57BL/6J and DBA/2J were assessed for diurnal variations in sensitivity to the effects of nicotine. Results indicated that there is significant variation in sensitivity to both activity and body temperature depressant effects of nicotine in the melatonin proficient C3H/Ibg strain with maximal sensitivity occurring during the latter third of the light period of the light cycle and minimal sensitivity taking place during the last third of the dark phase of the light cycle.
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