submitting a form when a checkbox is checked

is there are way to submit a form when a checkbox is checked?

<form id="formName" action="<?php echo $_SERVER['PHP_SELF'];?>" method="get">
    <input type ="checkbox" name="cBox[]" value = "3">3</input>
    <input type ="checkbox" name="cBox[]" value = "4">4</input>
    <input type ="checkbox" name="cBox[]" value = "5">5</input>
    <input type="submit" name="submit" value="Search" />
</form>

<?php
    if(isset($_GET['submit'])){
        include 'displayResults.php';
    }
?>

That is what I have currently, but I would like to submit the form without a submit button, when the user checks or unchecks a checkbox. Any help?