In Spanish, native speakers typically learn (implicitly) or memorize (explicitly) the gendered article along with the noun, so instead of thinking "hmm, let me remember the gender of mapa" they'll just have that noun stored internally as "el mapa". It's still a matter of memorization (at least for words whose gender violates the typically spelling heuristics), but it's not really conceived of as memorizing the word and then separately memorizing its gender. And of course, there will always be rare or specialized terms that a native speaker might recognize but confidently know the gender. This is especially true for the small set of nouns whose gender varies by region or context.