The exciting of receptors as such cannot specify objects or events in the world, that is, the sources of the stimuli. There are many answers. The trouble is that this pattern changes with every movement of the observer. This is Titchner's context theory of meaning, the climax of classical empiricism, but Koffka refuted it. This is the motor theory of meaning.
Meaning depends on habits of responses, on association learning , or on response-tendencies .
This is nativism or rationalism. It has all sorts of unwelcome implications. It is Helmholtz's ingenious combination of rationalism and empiricism. Despite the plausibility of this theory and its widespread acceptance, it has difficulties. Stimulus information can be defined as invariants in the flow of ambient energy.