          humanAction = 0;
        }
        if(lastKey == 39) {
          humanAction = 1;
        }
        if(lastKey == 38) {
          humanAction = 2;
        }
        if(lastKey == 40) {
          humanAction = 3;
        }
      }
    };

    var humanAction = -1;
    function enableHuman() {
      if(!humanControls) {
        humanControls = true;
        var a = new Agent();
        a.forward = function() {
          this.action = humanAction;
          humanAction = -1;
        };
        a.brai