Creatures, Technology, and Scientific Psychology
2.6 Experimental Epistemology
Between the folds of the awareness of agency in perception—which was first grasped by Fichte, then served as a basis for Helmholtz’s physiological psychology, and ultimately reached neurophenomenology—a completely new conception of the a priori emerged in the second half of the ninetenth century. As we shall see, it was to provide the starting point for Rudolf Magnus’ research program.
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In the light of this new idea of a priori and through sustained experimentation, Magnus draws upon the work on the “integrative action of the nervous system”
conducted by Sherrington, whom he quotes with the utmost admiration in every paper. “And integration—Magnus writes—is especially necessary in the case of posture, because nervous excitations arising from very different sense organs are flowing towards the postural centers in the brain-stem, and must be combined so that a harmonizing effect will result” (p. 340, 1925).29
The strange fate of this man, who died only a few months before he was in all likelihood about to receive the Nobel Prize, is curiously reflected by the transmis- sion of his theoretical testament: a lecture significantly entitled “The Physiological A Priori” (1930)—one of a series of lectures he was meant to deliver at Stanford University and which were published posthumously. What makes this an interesting text is not only the overview it offers of Magnus’ understanding of man but also the fact that an imaginary dialogue may be read between its lines, a dialogue which had evidently shaped Magnus’ research and has Helmholtz as its interlocutor.
This emerges in a remarkably clear way when we compare this lecture with “The Facts of Perceptions,” the paper which Helmholtz had given 50 years before.
Magnus draws upon its arguments, further explores its themes, develops its sugges- tions, and clarifies the various points made by Helmholtz, setting his own contribu- tion against such background. Magnus writes: “We possess numerous mechanisms acting unconsciously and partly sub-cortically which prepare the work beforehand for our psyche, and the results of which are a priori present before sensory percep- tion and psychological awareness come into play” (p. 103). The stance of our body, which is determined not just by our sensory structure but also by our orientation with respect to gravity, is the a priori foundation for how we intuit and think of the world, the reality of which would otherwise be ungraspable. Thus, if a person is color-blind (red-green “dichromatic”), their sense impressions of the outside world—say, a green apple tree with red fruits—will be incomprehensible to a normal- sighted (“trichromatic”) person with the normal ability to distinguish col- ors. “The nature of our sensory impressions—Magnus states—is thus determined a priori, i.e. before any experience, by this physiological apparatus of our senses, sensory nerves and sensory nerve centers.” These are the fixed mechanisms of our sensory apparatus which determine the nature of experiences. “But beside these, other ‘active’ processes (reflexes), acting through the central nervous system, also influence our sensory observations and help to determine them a priori” (p. 99).
What Magnus is referring to is precisely a series of reflexes—constituting “a real physiological a priori “(i.e. the righting reflexes)—which enable the “normal” posi- tioning and orientation in space typical of each species. This is the Kantian-Fichtian heart of Magnus’ work. But if this is the case, it is reasonable to posit an interplay between the processes of knowledge-acquisition and their results: “Since all study, analysis, and understanding of the events in the outer world are conducted through
29 Nervous impulses, which can influence posture, arise (1) from the labyrinths, (2) from the pro- prioceptive sense organs, (3) from exteroceptive nerve endings of the body surface, and (4) from teleceptors, reacting to distance stimuli, such as the eye, the ear, and the nose (Magnus 1925).
2.6 Experimental Epistemology
the senses, a scientific worker surely ought to know what are the fundamental mech- anisms of his body and of his nervous system which determine the results of his work.”30 With this final statement, questioning the dependence of scientific observa- tions upon the observer’s biology, a lecture that sheds light on two centuries of natu- ral science comes to a close. As we shall see, these pages resonate with the extraordinary view which Magnus had borrowed from von Uexkull (1903).
Upon Magnus’ death, the chair of Physiology fell vacant. Dusser de Barenne, who had been a close associate of his, applied for the position, but for reasons that have nothing to do with science—as is all too often the case in academia—the chair was assigned to someone else. Dusser de Barenne quit Holland for Yale. Here, in order to delineate the entire central system subserving bodily sensation, he contin- ued to carry on the same experimental procedure he had developed in his studies with Magnus: local strychninization. This technique consisted in the local applica- tion of strychnine to various areas of the cerebral cortex, combined with clinical observation of the animal’s exaggerated responses to stimulation.
Once at Yale, Dusser de Barenne demonstrated in a series of experiments that this procedure, being a more precise tool, was preferable to the two most common methods at the time: the method of extirpation—employed by Magnus, for exam- ple—which consisted in removing areas of the brain in order to study residual func- tions and that of electrical stimulation, based on the electrical stimulation of different brain loci and peripheral nerves as a means to map sensory and motor functions.
Both techniques presented some significant limits.
The crucial point that emerges from Dusser de Barenne’s work, in line with the neo-Kantian physiological tradition to which he belonged, is once again an innova- tive search for the physiological foundations of the a priori. Dusser de Barenne believed these could be found in cortical integration: he constantly put his practical skills to the service of this principle, which would appear to have been the lodestar of his experimental intelligence. This explains the considerable attention he paid to the development of a wide range of techniques: from local strychninization to lami- nar thermocoagulation,31 from the later coupling of the strychnine method with the recording of the electrical activity of the cortex (Dusser de Barenne and McCulloch 1938, 1939) down to chemical neuronography as a means to study communication between different regions of the brain. On the other hand, from this perspective we can also understand his constant attacks on the classic localization theory, “with its assumption of a sharp, point-to-point, geometric projection of the body on the cor- tex, with its centers for separate psychic functions” (Dusser de Barenne and McCulloch, 1939). Dusser de Barenne endeavored to demonstrate that the a priori was rather to be grasped in the organization and integration of the sensory-motor
30 Foreshadowed here is the key theme of the second cybernetics.
31 “The principle of the method is very simple. Local application of moderate heat to the exposed cortex for short periods of time results in destruction of the nervous tissue. By using different temperatures and different periods of application it is possible to ‘dose’ the depth of the destruc- tion, and thus to produce laminar lesions” (p. 517) (1934).
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functions in the cerebral cortex, which was seen to work as a whole through its system of neural connections.
This integration was studied by employing both electrical methods (electrical recording) and chemical ones (local strychninization), which represent “a powerful tool for delimiting the origin and ending of neurons in the central nervous system”
(Abraham 2003). At the same time, these methods paved the way for the momen- tous transformation which brought about the development of the cognitive sciences and technologies, particularly with McCulloch.
This mode of research sheds light on one important aspect of the transformation highlighted by Sheets-Johnstone (p. 181), when she observes that the de-animation of perception and the rise of cognitivist science are two intimately related phenom- ena. The reason for this is clearly connected to experimental praxis, as McCulloch explicitly confirms: “When one is working on the physics and chemistry of the anesthetized brain, as I was, one is doing biophysics and biochemistry necessary for neurophysiology, but falling short of physiology because the nervous system is then deprived of its functions; but even if it were working properly it would still be only physics and chemistry and not physiology unless one were studying the function also” (McCulloch 1974). Indeed, the neurophysiologist who anesthetizes the brain to study its mechanisms, connections, and organization isolates the brain, as a coherent whole, from any context and therefore ignores its relations with the out- side. The remarkable efforts made by cybernetics researchers largely go in this direction.32