When we talk of academic research, particularly in the genre of sciences, abbreviations are staple and indispensable. They surely help to bring down the wordiness of complex sentences but there major use is down to bring down the word count of the manuscript and hence they are embraced in the academic community with a lot of preference.
The use of abbreviations has an influence in the design and figures of the paper and a lot of unnecessary use of abbreviations does make the paper difficult to read. They are particularly more troublesome for journal reviewers when they receive the figure legends separate from the figures.
If as an academic writer, you avoid using unnecessary abbreviations in your figure design, it will benefit you in ways more than one. Audience often have less time and attention span to understand figures and with minimum use of abbreviations there we make their task far easier.
When you have to link the use of abbreviations in figures as well as text in the manuscript, avoid the use of abbreviations that appear only at one or two places in the text and nowhere else. This does not create vagueness and ambiguity for the reader and they are able to establish a better link between the table and the text. It is also true for reviewers and not just readers so do not create an extra barrier in the understanding of your document by the reader. When you have coined or used an abbreviation in the text of the manuscript, it is more acceptable to use it in figured but still not recommended.
In a situation when the abbreviation you wish to use has been used extensively in the literature review, it is more acceptable to use it. But if you want to make you work get appreciated and accepted in the community outside your academic area, it is more recommended that you minimise the use. It would enhance the accessibility to a broader audience as they would not be apprehensive of terminology that is acronym or abbreviation specific to a sub field.
If you wish to use some abbreviations that are ubiquitous in nature, it is perfectly fine to use the as they would not come in your of widening your audience and understanding of your manuscript. It is all the more good to accommodate those globally accepted abbreviations in figures that have already been used in the text before.
