Just now, my brain feels as if it’s trying to be like the Tardis (you know, bigger on the inside …)

This question about learning lines – beloved of audiences at talk-backs – poses itself afresh every time a new production looms on the actor’s horizon. And I can’t help feeling that by now I ought to have the answer to making the learning process easier.

But I don’t.

What I have come to recognize as I get older is that there is a more distinct difference between my short-term and long-term memory. I don’t mean that I can’t remember the name of the Prime Minister or what I had for breakfast (although I have been known recently to put my cell phone in the refrigerator.) But I have become acutely aware that these two mental muscles work in very different ways – at least in my case.

Some people maintain that one’s memory improves with practice. I’m not sure that that’s true – but I do think that one acquires a variety of tricks to help with the torturous process of learning a script, not least because it’s usually a test of endurance.

When I was 10 or 11 years old, I remember mugging up for exams by learning my notes by heart – literally taking them to bed, reading and re-reading them before going to sleep, and then regurgitating them the next day in the exact form I had learned them. It wasn’t a process that made for insightful analysis of material – but what the hell, when you’re comparing the site, situation, and functions of the ports of Liverpool and San Francisco, you look for the easy way out.

Intensely boring though they may have been, childhood experiences like these made me adept at absorbing large quantities of material for short-term use and then scraping the palimpsest clean, ready to be written over for the next assignment. And later on it’s a great skill to have if your agent sends you twelve pages of copy to be learned for a session the following day – but don’t expect a word of that stuff to be there next week.

I once watched a fascinating documentary about the Danish recorder player, Michala Petri. A dazzling virtuoso, I saw her play florid passages of Baroque music at great speed and with complete technical assurance, and I remember her saying that the only way she was able to master such pieces was not to have to think once about what her fingers were doing. By committing the notes and the fingering to a deeper, more instinctive muscle memory, she was then able to focus on her interpretation of the music.

Musical virtuosity relies on far more than the player’s confidence that she knows the notes, of course – and I can hardly imagine what it is like to be a prodigy, infant or otherwise! But I’m intrigued by the question of how one transfers the retention – or rather, the recall – of a script from the short-term mental filing system to a more deeply ingrained memory that allows freedom and spontaneity in performance.

If I find the solution, I’ll post it here – and I’ll probably have fewer pre-show nightmares like the one where I discover that I’ve missed four pages of my script that were stuck together and we go up in ten minutes. But meanwhile, as I try to assimilate the text of Rory Fellowes’ luminous play A Victorian Eye, I’ll have to adopt the method of every other actor faced with “learning all those lines.”

Learn them one by one.