Navigating the timeline using labels?

I have a slideshow and am using “Interval” to advance the images. They fade in & out over 12 frames. I want to allow the user full control of the slideshow by providing movie playback controls. I have frame labels for each image in the timeline. Each image is labeled “image”. Providing a back and next button, how do I make the playhead jump to the prev/next image when the prev or next buttons are clicked? My code is below. Thank you for any help.

var myInterval = setInterval (nextSlide, 3000);

function nextSlide () {
slideshow_mc.play();
}

next_btn.onRelease = function() {

}

prev_btn.onRelease = function() {

}

play_btn.onRelease = function() {
myInterval = setInterval (nextSlide, 3000);
slideshow_mc.play();
}

pause_btn.onRelease = function() {
clearInterval(myInterval);
slideshow_mc.stop();
}