Acute Effects of Cannabis on Cognition and Mobility in Older HIV-infected and HIV-Un-infected Women

The purpose of this study is to try to understand and explain why HIV-infected and uninfected women who use cannabis (marijuana) currently, or have used cannabis in the past, have higher risk of having experienced a fall in our earlier analyses in WIHS. This study will compare what happens when women are given cannabis compared with placebo, on measures of mobility, including walking speed under walking conditions that vary in terms of difficulty; for example normal walking and walking while reciting alternate letters of the alphabet, as well as measures of balance and cognition (for example attention, memory).