It might be useful to learn of learning and memory defined the broadest terms as like the food pyramid.
Yes, there are certainly different ways of encoding information in the body that effect behavior in different ways.
My skepticism comes when I think about the information passing through consciousness (the top of the pyramid). The human mind is processing tons of information every second -- much of it from external stimuli, but also integrated with information from memory. The human brain looks very much like a processor of information -- its neural networks learning to translate vast amounts of information into simpler, symbolic concepts that can also be fed again through neural networks to translate into yet finer concepts. The building and refining of these neural networks is certainly a way of encoding information in neurons. But this information works more like a software program -- other information flows through this system to generate new ideas. To me, the brain works like a computer processor (albeit of a more sophisticated, neural net type) along with some of the RAM needed for establishing relationships between neurons in this neural net, but where's the hard drive? I don't think most of the instantaneous information recall is being pulled from DNA coding or epigenetic memory.
Nor do I think the linkages between neurons are storing the incoming information from stimuli nor the outgoing symbols and concepts after processing it. They certainly rearrange their linkages in response to information flowing through them -- they are learning to process better and come up with new concepts and ideas, but I don't think they are storing the ideas themselves. The information flows through the brain only long enough to process it into something else.
Maybe the answer is that we are not, in fact, storing memories at all -- only the relationships and connections our neurons formed as they processed past experiences into new concepts and ideas. Our memories are just ghost imprints that fade over time as neuron linkages shift and change from new stimuli and ideas.
Maybe our brains are just one big reality filter, simplifying information into symbols and concepts encompassing broader and more global swaths of reality over time.
Consciousness, though, seems like it's inside that information, inside those symbols and concepts. And if that information is just a simplification, symbolization of reality in the first place, what the hell is our brain anyway? I think I've just spun this one into a circular reference, which probably means I'm getting too close to an ontological primitive (consciousness?) where causality starts to break down.
Bottom line: At least some of memory is stored in something other than the structure of the brain.