var header_images_arr = ['sight','smell','hearing','taste','touch'];

function getHeaderImage(sense) {
	if (typeof(sense) != "undefined") {
		var imageID = sense;
	} else {
		var imageID = getRandomImage();
	}
	return "images/topRight_"+imageID+".gif";
}

function getSenseImage(sense) {
	if (typeof(sense) != "undefined") {
		var imageID = sense;
	} else {
		var imageID = getRandomImage();
	}
	return "images/senses_"+imageID+".jpg";
}


function getRandomImage() {
	return header_images_arr[Math.floor(Math.random()*header_images_arr.length)];
}