Assembly pointers for variable binding in networks of spiking neurons
We propose a model for binding of variables such as the thematic role of a word
in a sentence or episode (e.g., agent or patient), to concrete fillers (e.g.,
a word or concept). Our model is based on recent experimental data about
corresponding processes in the human brain. One source of information are
electrode recordings from the human brain, which suggest that concepts are
represented in the medial temporal lobe (MTL) through sparse sets of neurons
(assemblies). Another source of information are fMRI recordings from the
human brain, which suggests that subregions of the temporal cortex are
dedicated to the representation of specific roles (e.g.,subject or object) of
concepts in a sentence or visually presented episode. We propose that quickly
recruited assemblies of neurons in these subregions act as pointers to
previously created assemblies that represent concepts. We provide a proof of
principle that the resulting model for binding through assembly pointers can
be implemented in networks of spiking neurons, and supports basic operations
of brain computations, such as structured information retrieval and copying
of information. We also show that salient featrues of fMRI data on neural
activity during structured information retrieval can be reproduced by the
Reference: R. Legenstein, C. H. Papadimitriou, S. Vempala, and W. Maass.
Assembly pointers for variable binding in networks of spiking neurons.
arXiv preprint arXiv:1611.03698, 2016.