Dealing with mental gaps.

[faa2010]

Is normal that after practicing the piece by heart, practicing it every day (or at least once a week), one day you forget a part of the piece?

They told me that the solution is practice, practice and more practice. I have done it, but there are some days or some moments that I cannot remember a section and I get more frustrated.

What can I do?

[pianisten1989]

Go through the piece carefully, so you know every note.. Or at least all chords, so you kind of know every note... do that once a week, and you wont forget it...

[mistermoe]

They told me that the solution is practice, practice and more practice.

That's exactly the wrong way! If u want to really know a piece by heart, u have to understand it. Devide it into many different sections, look and memorize the harmonic progressions.
U could try to play it in a different key. That will force you to think about all that stuff and help u understand.

In fact, the problem is, that you never know how well u really have memorized a piece until u play it in public. So ask a friend or your family to listen to you playing. But not spontaneously. Arrange a time and date. This way you will get into a concert mood (or at least a little bit).
Or record yourself. It has a similar effect.

I'm sure that if u use the search function, u will find tons of threads and useful ideas about memorizing.

[mistermoe]

I forgot about something very important.

Learn the notes of your pieces away from the piano. Just look at the sheets and play it in your head/sing it. And then the other way round. Play it in your head without looking at the scores. Play it on the table. Hands seperately.
If you are able to do this, u can say that you can really play it by heart.
Of course in concert you could still have mental gaps, but that's probably because you are just a human being. HA! (at least i suppose  )
But you can minimize the chances of this happening.

[mazeppa]

I strongly second mistermoe