In APA style, acronyms are capitalized only if the full term they represent is conventionally capitalized. If the full term is not capitalized (like "laser" – Light Amplification by Stimulated Emission of Radiation), then the acronym is generally not capitalized either. However, after the first use, you can use the acronym consistently.
Therefore, there's no blanket rule; it depends on the specific acronym and the full term it represents.