Thanks Lefty,
I'm confident my button is correct. It's connected to pin 6 and being pulled down via a 10k resistor. When pressed a 5v high signal is passed to pin 6. I have even tested it using the serial monitor.
I believe my issue to be in the loop of my code. I have a command which states if LOW run PONG, else run PATTERN. I think I need to extend it to say; RUN PONG if LOW, RUN PATTERN if HIGH but all my experiments have failed.
Currently, the code runs and displays PONG. When I press the button it switches to PATTERN. Pressing the button again doesnt do anything.