Contact is repulsive, but please note the "enclosed".
Dev Cell 2012 Jan 17; 22(1):5-6.
Previous models of neuronal dendrite arborization suggested that contact-dependent self-avoidance between dendrite branches prevents self-crossings within the arbor. Two papers in Neuron show how integrin-mediated adhesion to the extracellular matrix restricts dendrites to a two-dimensional space to optimize this mechanism (Han et al., 2012; Kim et al., 2012).
Burgess, Robert W; Garrett, Andrew M; and Tadenev, Abigail L D, "Contact is repulsive, but please note the "enclosed"." (2012). Faculty Research 2012. 17.