When I started preparing those courses I felt I am walking into unchartered territories as the academic literature is there , but as often happens in academic literature it is removed from real life and, not to my surprise, often unclear and seem to be more about filling pages in books then actual research and education.
When I look at visual vocabulary I divide the subject to three parts:
The first is how we perceive. How do we collect information and how do we analyze and internalize it. If you study nutrition you have to understand how your digestive system works, how the body handles different sources of energy and the building blocks of your body.
It is the same thing with design, if you don’t understand how the brain works and how we handle each and every signal that is gathered, all you are left with is fashionable trends and your personal aesthetic taste. (which explains why there is so much shitty design out there)
The second part is to understand the internal logic of the visual vocabulary. We know how the mind works, we know what it does with information, and now it is time to see all the different types of information we have, or can build, in order to get the maximum effect of passing our message across.
This part I generally divide into three groups (what? Yes, three groups. Everything in the world is divided to three groups, so? Ok, maybe it is just a private obsession, but still it works…) the groups are : colors, shapes, and fonts.
Color is the most immediate factor in the visual world, it is a primal instinct that has been part of our evolution and our way of life, keeping in mind we do have a limited spectrum of colors we see, and each living creature has it's own spectrum. (For example, bulls are color blind. The red cape waved in front of his face? It is red for our benefit, not for his.) of course there are cultural variations about color perception and it's meaning, but when it comes to western society, all in all we are playing in the same field, with more or less the same rules. Some of the best anecdotes I bring to my students is what happens when western thinking creates color related faux pas in other areas of the globe.
The second part is made out of forms and shapes, in a cubistic way of thinking. A layout is basically just the use of shapes, a logo is a combination of forms. Each form holds a significance on the most basic level of our recognition system, some are soft and inviting, some are pointy and scary, some can be symmetrical and bring a sense of stability and harmony, and some are chaotic and send signs of energetic movement and strength. It's a whole world summed up into the basic conceptual shapes, and it always has an effect on us we are not even aware of.
The third and last part is more directed to designers, although it appears a lot in art in the last fifty years – fonts. Again, there is a cultural baggage that comes with each font, a story, a meaning. It is up to the good designer to know these stories, and use them in his work. Choosing fonts is much more than an aesthetic decision, and this is why I cringe every time I see a young designer using a strange font he "found" because it looks cool in his mind, while completely shooting himself in the leg as the message the font gives is counterproductive to the project he is working on.
That's it. If you study these three fields, you will be a better designer, and probably also a better artist. After that? Break all the rules. Do what you want. But first? know and understand how visual vocabulary works.