To change notification / activity stream related settings, navigste to the settings screen.

settings - notification section

Show Wiki Notifications in the JIRA Activity Stream

This setting allows you to toggle on/off whether activity related to team pages (like creating a page, commenting on a page, attaching files, etc) should show in the general Jira activity stream.

Note: disabling this setting simply affects whether items show in the activity stream. If you re-enable this setting, historic changes will automatically show up again.