What is counted as changes to "last updated"?

Within the filter section or in the list sorting option, you will find the option to filter or sort by last updated (cf. the bluedots on the picture below). The following is taken into account when updating the time stamp:

• Changing the element’s content (title, abstract, text field, or user search field)

The following is not taken into account: 

• Interaction with the element (comment, rate, watch, and relating)