Activities page layout - how to add Accounts?

Activities page layout - how to add Accounts?

Hi- 

Under Activities in the top navigation, I usually have All Activities displayed. It does not have an Account column. It has only Contact Name column. How do I add Account name column to this page? I haven't found under Customization where I could do this. 

Not all my Accounts have contact names, so I like to be able to view the Account name when there is no Contact information.