how to enable word highlight in the dropdown menu

[applemate]

typing 'ala' the character ala in alabama is highlighted. That screen shot is from twitter demo. How to enable that mode?

[applemate]

sorry, I thought the setting is different from twitter typeahead but not. Just do like this to enable highlight

$('#address').typeahead({
        highlight: true
    }, {
      displayKey: 'description',
      source: addressPicker.ttAdapter()

    });