Will this work? I get .16. I suspect correlation is not the right tool though. Logistic regression?
datafile0 <- data.frame(gender=c("Female", "Male", "Female","Female","Female", "Male"),
cognitive=c(4.56, 6, 5.43, 2.88, 3.55, 3))
datafile0$gender <- ifelse(datafile0$gender == "Female", 0, 1)
cor(datafile0$gender, datafile0$cognitive)