Are Qt signals to another thread queued?

Question

If I have:

class Worker : public QObject
{
  Q_OBJECT

public:

  Worker();

public slots:

  void doStuff();
}

And run it like this (assume we are in class Foo):

auto worker = new Worker;
connect(this, &Foo::stuffRequested, worker, &Worker::doStuff);
QThread workerThread;
worker->moveToThread(&workerThread);
workerThread.start();

Now if I emit stuffRequested() so frequently that the Worker cannot keep up what happens? Are the signal invokations queued?