Maybe even more than "consciousness", "culture" is a word that everyone uses but few are comfortable defining. Perhaps it's commonly thought of as art, design, custom, folklore, ritual, etc., but even in anthropological circles, in which culture is the core of the discipline, the word often has a peculiar and somewhat frustrating vagueness. It might be defined, for example, as the shared or common values, traditions, norms, etc., "of a people", but how does that relate to the actual individuals that make up the "people", for example? Is there a difference between these "shared" values and individual values? How "shared" do such values need to be? How do we determine the boundaries of the "people"? And where do these shared values actually reside, after all?
Another hypothesis, then: linguistic consciousness provides the basis for a structure of sign/symbol pairs (a "sign" being a perception that evokes or activates a "symbol", which is a ready-made and meaningful element of consciousness), a structure which is imprinted on the mental apparatus of each individual making up a particular cultural group. If we use the admittedly slippery term "meme" to refer to such sign/symbol pairs, then we can refer to the entire structure of such pairs as the individual's "memotype", in an obvious analogy to the individual genotype. And just as each individual's genetic blueprint is unique, yet sufficiently like other humans' to constitute a species, so each individual memotype is unique, but similar enough to allow communication and shared understandings of certain values, etc. -- similar enough, in other words, to constitute a culture.