Is there a way to iterate a function for each element of a large list in R?

Question

I would like to perform a ROC curve analysis using the pROC package in R. I have a dataset (dataframe) of 45 subjects; each one of them has about 1000 values in a column called "spike_conn" that should predict my categorial variable "Resected" (another column in the dataframe).

I have created a large list of 45 dataframes using the split function like this:

 list_data <- split(database_all, database_all$patient)

Then I have tried to use a for loop to perform the roc curve function for each element of the list (45 dataframes) like this:

Results_list <- list()
for (p in list_data) {
  rocbj <- lapply(p, roc(list_data[[]][,29], list_data[[]][,5]))  
  Results_list[p] <- rocbj$auc
}

But it seems to be wrong, can somebody help? Thank you in advance