Archives for the Month of February, 2014

Primal Generative: Form Constants & Entoptic Geometry

Subjective_visual_phenomena_-Johann_PurkinjeSubjective Visual Phenomena – Johann Purkinje [From Beiträge zur Kenntniss des Sehens in subjectiver Hinsicht, 1819]

The most primal generative visual experiences may be ones created by the visual cortex alone, or ones involving the visual cortex in close collaboration with entheogenic triggers or external psycho-visual simulate, such as stroboscopic lighting. Precursory research material includes Johann Purkinje’s investigations into subjective visual phenomena in Experiments on the Physiology of the Senses and Heinrich Klüver’s later extrapolation of the four groups of entoptic visual phenomena he called Form Constants. The four groups, lattices, cobwebs, tunnels, and spirals, where annotated by Klüver while studying the effects of mescaline.

A recent paper by Tom Froese and others explores the role of Turing instabilities in the generation of spatio-temporal patterns in the disinhibited visual system and its relationship to the prevalence of certain geometric patterns.

‘One of the originally proposed mechanisms for geometric hallucinations is that of a neural Turing mechanism, embodied in the Wilson–Cowan equations [1973] [..] For example, action potential propagation along a neuron’s axon can be directly described by reaction–diffusion equations, and reaction–diffusion equations are analogical to the Wilson–Cowan neural network equations (H. R. Wilson, 1999, pp. 267–268). We can think of the reaction component as the interactions between neuronal cells, and of the diffusion component as the spread of neural activity through local synaptic connections. Similarly, the local structure of neural interconnectivity dictates the type of emergent phenomena that can be produced. Neural network models of geometric hallucinations have gradually incorporated these empirical insights from neural anatomy and physiology, including the spatial arrangement of different neuronal cell types.’

FormConstantsHeinrich Klüver’s Form Constants

The paper goes on to say:

‘A striking feature that differentiates geometric hallucinations from other visual experiences is that they are generated intrinsically when the subject has been decoupled from its environment. The patterns form irrespective of our lifetime learned memories. Indeed, they could be considered internally directed perceptual experiences, since if the proposed models hold true, they are directly formed from the actual biological structure of the visual system. We are said to have a strange subjective experience of looking into oneself, where the patterns we see directly expose the underlying operation of our brains.’

The hyper-chromatic geologies found in the generative work of John Mccabe, who uses Turing instability equations, certainly hints at psychedelic topologies that can be created by these kinds of mathematical exchanges. Its a tidy thesis to suggest that visual representations, of this kind, are isomorphic to the processes involved. When Tim Leary compared psychedelics, in a sense, to the microscope, perhaps it was not entirely metaphorical. If these models are correct the psychotropic vision is a snapshot of the visual cortex looking at itself and looking at its own neural processes – mimicking recursive loops, and algorithms, in order to plot and sketch form constants on its own display.

In The Signs of All Times: Entoptic Phenomena in Upper Palaeolithic Art Lewis-Williams and Dowson explore evidence of motifs and compositions derived from entoptic phenomena in prehistoric art. The earliest humans may have ascribed enough relevance to entoptic visualisations to begin the journey into pictorial representation and subsequently writing.

Further Readings:

Turing instabilities in biology, culture and consciousness on the enactive origins of symbolic material culture – Tom Froese

Purkinje’s Vision: The Dawning of Neuroscience – Nicholas J. Wade and Josef Brožek [PDF]

Mechanisms of Hallucinations – Heinrich Klüver

What Geometric Visual Hallucinations Tell us About the Visual Cortex – Paul Bressloff and Jack Cowan

Aesthetics Beyond the Phenomenal: Tony Conrad’s THE FLICKER

Previously at Dataisnature:

Kyuha Shim – Spherical Form Constants & Syllabic Constructs

Form Constants – Wendy Collin Sorin

The Generative Song & Sound Pattern Matrixes of the Shipibo Indians

Mind Expanders – Haus-Rucker-Co

Descriptive Illustrated Catalogue of the Sixty-Eight Competitive Designs for the Great Tower for London – Fred. C. Lynde [1890]

great tower for London

While many of the entries to a completion to design a new tower for London, in 1890, appear as poor copies of the Eiffel Tower, other proposals transcend the architectural traditions and clichés of the time. Futurist monoliths and space-conquering rockets wait alongside Babelesque towers and medieval obelisks preparing for lift-off. The catalogue documents a structure with ‘a captive parachute to hold four persons’, a tower with a spiral railway climbing its exterior, a 1/12-scale model of the ‘Great Pyramid of Giza envisioned as a colony of aerial vegetarians, who would grow their own food in hanging gardens’. The fusion of styles generate anachronistic hybrids which look both forwards and backwards in time, many will be recognisable to those who have pondered the cities described by Calvino or Lovecraft.

great tower for London

great tower for London

great tower for London

great tower for London

great tower for London

great tower for London

great tower for London

great tower for London

Related:
Yuri Avvakumov – Agitarch Structures: Reconfiguring Utopia
The Spatio-Lumino-Chronodynamic Towers & Sculptures of Nicolas Schöffer