Sorry if this sounds like a humblebrag, but I would sing songs backwards as a kid but then stopped after some time. Surprisingly it all came back few years ago and I can still hum the songs with some minor efforts. Human brains are fascinating.

I think this happened when I was learning Devanagari script which is an Abugida and it makes it (relatively) easy to talk backwards just by reversing the syllable order.

E.g. "मेरा जूता है जापानी" can be reversed pretty easily by just switching the syllables "रामे ताजू है नीपाजा"