Ermentrout and Cowan (1979) applied bifurcation and group theory to neural-field equations to explain visual hallucination patterns — a neuroscience target, not morphogenesis
Ermentrout and Cowan's "A mathematical theory of visual hallucination patterns" (Biological Cybernetics 34(3):137–150, 1979) carried the Turing-style analytical toolkit — instability analysis, bifurcation theory, the emergence of doubly-periodic solutions — into the neural-field equations. Per the authors' own abstract: "Neuronal activity in a two-dimensional net is analyzed in the neighborhood of an instability. Bifurcation theory and group theory are used to demonstrate the existence of a variety of doubly-periodic patterns, hexagons, rolls, etc., as solutions to the field equations for the net activity. It is suggested that these simple geometric patterns are the cortical concomitants of the 'form constants' seen during visual hallucinosis."
The paper is built on the Wilson–Cowan field equations rather than on Amari (1977), but because the two formulations describe the same object (claim-wilson-cowan-and-amari-neural-field-formulations-are-the-same-object), the pattern-formation machinery that Turing's morphogenesis work motivated did reach the Amari-family neural-field formalism. Crucially, the target was a neuroscience phenomenon — spontaneous cortical activity patterns underlying geometric visual hallucinations — not embryonic or developmental-biology morphogenesis. The same lineage later extended to other adult-cortex phenomena (rhythmogenesis, sleep, epilepsy), never looping back to developmental patterning (claim-no-amari-1977-neural-field-application-to-morphogenesis-found).
This is the affirmative half of a two-sided finding: the Turing toolkit went somewhere in the neural-field lineage, and that somewhere was neuroscience. The originating thread that motivated the search is Amari's own reaction-diffusion debts in claim-amari-1977-neural-field-paper-rooted-in-reaction-diffusion-morphogenesis-literature.
Source
“Neuronal activity in a two-dimensional net is analyzed in the neighborhood of an instability. Bifurcation theory and group theory are used to demonstrate the existence of a variety of doubly-periodic patterns, hexagons, rolls, etc., as solutions to the field equations for the net activity. It is suggested that these simple geometric patterns are the cortical concomitants of the 'form constants' seen during visual hallucinosis.”
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