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The brain restructures itself as it computes. Changes in the structure or function of the brain which result from activity or experience are called “plasticity”. Perhaps originally this term was meant as an analogy to thermosetting plastics, whose structure is relatively fixed most of the time, but can undergo dramatic changes under the right conditions (heat). These days the term is applied more broadly, and doesn’t necessarily denote processes with long periods of stability, punctuated with short periods of change. These days pretty much any change in the brain which is caused by activity or experience is called “plasticity”.
There’s a couple of levels at which “plasticity” phenomena are studied.
On the electrophysiological level, there are various phenomena which alter the response characteristics of individuals synapses (SynapticPlasticity), and individual neurons (IntrinsicPlasticity). These are often divided into ShortTermPlasticity (which is what might be called in other fields simply the “temporal dynamics” of the response functions), and LongTermPlasticity. LongTermSynapticPlasticity is is considered to be the most likely memory substrate (see SynapticWeightBasedMemory), although the evidence is not yet overwhelming that it is the memory substrate, and there are some dissenters.
Another grouping of types of low-level plasticity is HomeostaticPlasticity.
On a more macro- level, there are lots of experiments showing how the “map” of regions in the brain (as well as the intra-regional maps) are altered in a regular fashion by experience. Most often the “experience” consists of somehow shutting off one or another kind of sensory input, for example MonocularDeprivation studies.
Including map plasticity as a special case, ExperienceDependentPlasticity? looks at how not only maps, but any aspect of brain structure and function are altered by experience. In addition to cutting off inputs, experiments include having an animal learn a task, and then trying to determine the neurological correlates of learning. See for example MusicAndPlasticity.