Our insights in memory formation are still limited. The most studied candidate is LTP/D[1], the change of weights of synapses between neurons. Memory formation is a complex process though. While LTP can be induced with a short burst of spikes, its stabilization and maintainance depends on a sizeable number of molecules and genes. We still don't know at what level the memories may be stored, it could be the level of single synapses, groups of synapses, the level of single neurons or ensembles of neurons.
There are experiments involving fear memory that have shown that a fearful event can be "stored" in an ensemble of identifiable neurons, and even be turned on and off [2].
Then there are brain rhythms and sleep. Memories would become overwritten if they were stored in the same circuits over and over, so there are various theories about how memories are transferred to various parts of the cortex via coordinated rhytmic activity or sleep.
Closer to your question, the data structure that our serial thinking brain uses is language. We think, reason and communicate using it. Language has a tree-like syntax, but semantics are an unsolved problem. There is even a theory that suggests that brain rhythms may encode "sentences" into thoughts via neuronal oscillations[3].
There are experiments involving fear memory that have shown that a fearful event can be "stored" in an ensemble of identifiable neurons, and even be turned on and off [2].
Then there are brain rhythms and sleep. Memories would become overwritten if they were stored in the same circuits over and over, so there are various theories about how memories are transferred to various parts of the cortex via coordinated rhytmic activity or sleep.
Closer to your question, the data structure that our serial thinking brain uses is language. We think, reason and communicate using it. Language has a tree-like syntax, but semantics are an unsolved problem. There is even a theory that suggests that brain rhythms may encode "sentences" into thoughts via neuronal oscillations[3].
1: http://en.wikipedia.org/wiki/Long-term_potentiation
2: http://www.silvalab.com.cnchost.com/silvapapers/ZhouNN2009.p...
3: http://osiris.rutgers.edu/BuzsakiHP/Publications/PDFs/Buzsak...