r - For a stats class assignment I have to show that the anova will pick up significance in cases where the t-test does not?

Question

How can I run a Holm-Sidak test on a repeated measures anova in R?

MeanSEP is the voltag potential from the result of a paper I have to recreate the statistical testing for in a class. I am looking for a significant difference between the conditions; Baseline, ABCD, DCBA, and 300.

Here is as far as I've gotten:

control1 = data.frame(
  c("m1","m2","m3","m4"),
  c(129.43,152.48,118.79,156.02),
  c(180.85,228.72,257.09,278.37),
  c(198.58,230.5,235.82,304.96),
  c(134.75,159.57,223.4,255.32))
colnames(control1) = c("subject","Control","ABCD","DCBA","300")
control=stack(control1) 

subject = rep(control1$subject,4)        # create the "subject" variable
control[3] = subject                   # add it to the new data frame
rm(subject)                               # clean up your workspace
colnames(control) = c("MeanSEP", "Condition", "subject") 

testc= aov(MeanSEP ~ Condition + Error(subject/Condition), data=control)
summary(testc)