how to get multiple checkbox values from html form

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form name = "TestForm" action="Video1.php" method="post" onsubmit="return validateForm()">

<table>


    <tr>
        <th> <input type="checkbox" name="ParticipantSelection[]" value="image1">
        </th>

        <th><input type="checkbox" name="ParticipantSelection[]" value="image2">
        </th>

        <th><input type="checkbox" name="ParticipantSelection[]" value="image3">
        </th>
    </tr>


</table>
<input type="hidden" name="AnswerCondition" value="BrowserCheckAnswer">


<button type="submit">Continue</button>

</form>

var validateForm = function(){
 var checks = $('input[type="checkbox"]:checked').map(function(){
  return $(this).val();
 }).get()
    console.log(checks);
    return false;
}