JavaScript Object Property editing

I'm creating (what feels like) a complicated script for use in creating a data based glossary as part of an in5 HTML 5 export. 

It takes a tab delimited text file and converts it into a js Array of Objects, each object containing the properties: term, definition, and link. Example below:

{
  term:"Term goes here",
  definition:"The definition goes here",
  link:"Page links go here"
}

My issue arrises when trying to edit the contents of objects via my Dialog with a listbox containing the terms, and edittext fields which default to the properties of the array objects as they are selected. I use event listeners to detect 'changing' and 'change' on the edittext fields like so:

// Edittext field for the Term
var displayTerm = displayGrp.add("edittext", [0, 0, 350, 20]);

// Edittext field for the Defintion
var displayDef = displayGrp.add("edittext", [0, 0, 350, 150],
  {alignment: ['fill', 'fill']},{multiline: true});

// Statictext field for the Link
var displayLinks = displayGrp.add("statictext", [0, 0, 350, 20]);

//Update the Listbox item with the edittext field contents
//putting these items in the 'change' event listener only 
//updated after a few unfocus/focus of other fields
displayTerm.addEventListener('changing', function() {
   var index = termListBox.selection.index;
   var newText = this.text;

   termListBox.items[index].text = newText;
})

//Update the object property with the edittext field contents
displayDef.addEventListener('changing', function() {
    var index = termListBox.selection.index;
    var newText = this.text;
    splitGlossArray[index].definition = newText;
    updateGlossData(splitGlossArray)
})

//Update the object property with the edittext field contents
displayTerm.addEventListener('change', function() {
    var index = termListBox.selection.index;
    var newText = this.text;

    splitGlossArray[index].term = newText;

    //Alerts to check array object properties
    alert(splitGlossArray[index].term);
    alert(splitGlossArray[index]);
    alert(typeof(splitGlossArray[index]));

    alert(splitGlossArray[index].term);
})

But its producing curious results. If given the example object above, when editing the field text and clicking away you get the following outputs in the alerts:

Term field editted to: "Term will never go here"

alert(splitGlossArray[index].term);
//Returns "Term will never go here"

alert(splitGlossArray[index]);
//Returns:
// {
//   term:"Term goes here",
//   definition:"Definition goes here",
//   link:"Page links go here"
// }

alert(typeof(splitGlossArray[index]));
//Returns: object

alert(splitGlossArray[index].term);
//a double check to make sure the term property 
//hasnt been overwritten
//Returns "Term will never go here"

So whats going on here? Why is the object property saying its being changed in my alerts, but the object overall is not?