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Carlos G. Dotti was first author of the 1988 study following axon and dendrite formation in cultured hippocampal neurons. ^[ref] The approach made a general cell-biological problem concrete: one cell develops compartments with different structures and functions. Following development in culture allowed temporal evidence to be combined with molecular markers of compartment identity.

Christopher A. Sullivan coauthored the 1988 study of neuronal polarity in cultured hippocampal neurons. The work combined repeated observations with molecular identification of developing dendrites. ^[ref] It supplied a way to test when an apparently similar neuronal process acquires a distinct identity, rather than inferring its history solely from mature shape.

Gary A. Banker coauthored work following the emergence of neuronal polarity in cultured hippocampal neurons. Sequential observations linked initially similar processes to distinct axon and dendrite outcomes. ^[ref] The culture model made cellular differentiation observable in the same cells through time, separating a developmental sequence from comparisons of unrelated endpoint images.

Microtubule-associated protein 2, commonly called MAP2, is a neuronal protein associated with microtubules and strongly enriched in many dendrites. It contributes to organization of the dendritic cytoskeleton. Enrichment makes it useful as an experimental marker, but marker abundance and the full functional identity of a cell compartment are different properties. ^[ref]

In cultured hippocampal neurons, MAP2 immunostaining helped confirm dendritic identity after processes had been followed through development. ^[ref] Combining time-resolved shape changes with a molecular marker is more informative than calling every short process a dendrite. Developmental stage, isoform and preparation conditions also matter when interpreting staining.

A neurite is an extension from a neuron's soma, used especially when the process has not yet been identified as an axon or a dendrite. This neutral term is useful in developmental biology: an early process need not already have the mature molecular composition or signaling role of either compartment.

Repeated imaging of individual cultured hippocampus neurons showed several initially similar neurites, followed by rapid elongation of one future axon and later differentiation of the other processes into dendrites. Shape at a single early time point therefore need not settle eventual identity.^[ref]

Neuronal polarity is the structural and molecular differentiation of a neuron into compartments such as an axon and dendrites. Different distributions of proteins, transport machinery and synapses support different roles in receiving and sending signals. This organization does not require every electrical event to travel in only one direction: action potentials can propagate back into dendrites.

In 1988, Carlos G. Dotti, Christopher A. Sullivan and Gary A. Banker followed individual embryonic rat hippocampus neurons in culture using repeated photography and time-lapse imaging. Several initially similar neurites preceded rapid growth of one future axon; staining for microtubule-associated protein 2 helped distinguish later dendrites. Following the same biological cells over time directly tested the developmental sequence, which a collection of mature shapes could only suggest.^[ref]