Phenomenology Life and Simplexity

1. PhenomenologyLife and Simplexity Jean-Luc Petit Université de Strasbourg

2. Plan • “The complexity of reality”  • Complexity – a threat to the living being • Simplexity: getting us out of predicament • Natural science and phenomenology • Constitution Theory a framework for simplexity

3. Plan • “The complexity of reality”  • Complexity – a threat to the living being • Simplexity: getting us out of predicament • Natural science and phenomenology • Constitution Theory a framework for simplexity

4. Palimpseste du Monastère de Ste Catherine, Mt Sinaï (IVe s)

5. Stars cradle Fly brain

8. Reaction of Belousov-Zhabotinsky Oxydoreduction of citric acid into a carbonic gas in which concentrations of bromate /bromure pass alternatively below and above a critical value under the influence of an autocatalytic coupling of states of the two substances, either oxidized or reduced. Periodicity of colour changes observed by Boris Belousov in a study of metabolism of glucose (1950)

9. Emergence in a network: u, v in same component becausethereis a pathfrom u to v. x, y in distinct components : no path. If one adds m random connections between the n nodal points of the network, as soon as m goes beyond n/2, a giant component develops, until it encloses all the nodes. An abstract mathematical model of the phase transitions and the appearance of structures out of chaos in dynamic physical or biological systems. T. Bohman, Science 323(2009)

10. Complex System = not completelyaleatorynorcompletelyregular. Brain: a mix of anatomicalsegregation and functionalintegration. G. Tononi et al, TICS 2/12 (1998)

11. Plan • “The complexity of reality”  • Complexity – a threat to the living being • Simplexity: getting us out of predicament • Natural science and phenomenology • Constitution Theory a framework for simplexity

12. A. Berthoz: « Nous vivons écartelés entre de nombreuses identités qui nous placent dans un entrelacs de toiles d’araignées sociales et psychologiques … » « L’homme d’aujourd’hui est un Thésée perdu dans un labyrinthe… »

13. Cerebral Cortex Basal Ganglia Striatum Subthalamic n. Globus Pallidus Substantia Nigra Thalamus Cerebral Cortex Multiplicity of functionalloops in the brainapparently incompatible with the stability of functioning of circuits E. Rolls The Brain and Emotion (1999)

14. Plan • “The complexity of reality”  • Complexity – a threat to the living being • Simplexity: getting us out of predicament • Natural science and phenomenology • Constitution Theory a framework for simplexity

15. The inventary of simplex solutions • F: 'X is an ingenious solution invented in the course of evolution to simplify (reduce the dimensions of) the problem posed by the complexity of the environment.' • F is then the general formula for drawing up an inventory of the remarkable features of living organisms – but a list still does not amount to a theory. • How does one get from a list to a Theory of simplexity?

16. A tool-box of simplifyingPrinciples • 'A simplex process, Berthoz tells us, is a process regulated by several principles... This list of principles is designed to provide a framework, inevitably incomplete and debatable, for specifying the concept of simplexity (4)'. • Only, this list knows no end: 'it is impossible to describe all the simplifying principles evolution has put in place: we discover more of them every day (73)'. • In the end, no procedure can be excluded: 'Evolution seems to have used any means available, adopting unpredictable paths, utilizing all the tools that physics and chemistry made available, with the sole end in view of simplifying (38)'.

17. Motor equivalence in gaze We can move our gaze by moving the eye or by moving the eye and the head or even by moving the whole body : For that the gaze movement needs to be coded sufficiently generally to be realized by any part of the body. The gaze movement is coded in a variable of velocity that is transformed in a signal of position according to the internal model controling the movement of the chosen limb. A retinotopic model map where each neuron is represented by its receptive field: The displacement of target in outer space is predicted by the change of activity in the map as a gaze-velocity signal is updated after the oculomotor command. No need of a higher cognitive spatial map to track the movement of targets in space. Proc. Natl. Acad. Sci. USA, 88, 9653 (1991)

18. Making a detour in trackingtasks: Instead of trying to continuously control the unpredictablychanging position of a movingtargetSubjectsintermittentlyminimize a composite variable s (a mixture of position, speed and acceleration) using a feedback (corrective) and feedforward (estimative) strategy in order to compensate for the unknowndynamics of the limbs-object system keepingitwithin the limits of one dimension. The hand movementneeded for that correction mightbe a simple ballisticmovementwith a stereotypedcinematic profile. Biol. Cybern. 77, 381 (1997)

19. Decidingwhere to look Self-initiated (not externallycued) eyemovementsbetweenalternatively possible targetsrely on the prefrontal cortical areas of decision-making in behavior. Decision condition: subjects are free to decide the direction of the forthcoming saccade. Dorsolateralprefontal cortex active in decision condition not in case of imposed saccades. Task: fMRIresults: Neuroreport 18(12) (2007)

20. Catching a fallingballthanks to an internal model of gravity: The brain triggers hand movementbased on the visual image of the objectcomplemented by an implicitknowledge of the accelerationeffect of gravity. In the shuttle (0 g) the anticipatorymovementoccuredearlierthan on earth. Prediction of movementissimplified by an internalization of laws of physicsmaking possible to simulatemovingobjects in the world with the body. Nature Neurosc. 4, 7 (2001) ---Lag of time-to-contact visual estimation (1g) ---Precocious TTC based on internal model (0g) Anticipatory biceps EMG response (0g)

21. Head stabilization for top-down control of locomotion: The task of coordinating the degrees of liberty of the limbs in walkingisorganizedfrom the head not the feet. The headisused as a mobile inertialplatformfreeing the body from the ground. Head kinematicsvideorecorded and reconstructed by computer (10 sj). Exp. BrainRes(1990) 82, 97-106

22. Differentbrain areas for egocentric and allocentricstrategies in spatial location: Orientingoneself in space supposes an ability to change point of view: fromrefering to oneself to taking an object or a landmark in the environment as frame of reference. Egocentrationactivates a network including: parietal (1) occipital (2) and frontal (3, 4) areas. Allocentrationactivates a partlydifferent network includingalsooccipito-temporal (7, 9) areas. J Cogn. Neurosci. , 169 (2004) Tasks : 1) Whichgarbagecaniscloser to you? 2) Whichcaniscloser to the redball? 3) Whichcaniscloser to the front of palace?

23. Perspective taking : two mental imagerystrategies for embodiment of the other a: ReflectionSymmetry: A tilts on hisleftwhen B tilts on his right and vice versa as if A sawhimself in amirror. b: Rotation Symmetry: A tilts on hisleftwhen B tilts on hisleft as if disembodying and adoptingB’s perspective. c: experimental setting: Subject on a ground trace in line with the rope of the acrobate. d: goniometerrecording the tiltings of the bar. e: videoof avatar acrobate tilting on his right (or left:f).Brain& Cognition (2009)

24. Plan • “The complexity of reality”  • Complexity – a threat to the living being • Simplexity: getting us out of predicament • Natural science and phenomenology • Constitution Theory a framework for simplexity

25. 'Any science has to replace, or economize on, experience, by reproducing, or prefiguring, facts in the form of thoughts, such reproductions being more readily available than experience itself, and therefore capable of replacing the latter in many respects (452) ... Science can itself therefore be regarded as a minimal task, consisting in representing the facts in the most complete manner possible and with the least expenditure of thought (E. Mach, Die Mechanik in ihrerEntwickelung, 1883, 461)'. 'This would-be principle is nothing less than an attempt at an ultimately rational explanatory principle, the mere grouping together of an entire complex of evolutionary facts in advance of any ideal reduction to elementary facts and laws, and this whether or not any such reduction will ever be realizable (Husserl 1913,IX, §.55).'

26. A Dynamic Model ofMorphogenesis The cortical map of a hand simulated • Formation of neuronal groups on the computer: • A: initial state of part (12 x 6) of a network of 144 excitatory cells and 2448 synaptic connections. • = cell — = synaptic connection, colors = strength of synaptic connection B: state after hand surface stimulation (activation of 3x3 receptors) : formation of neuronal groups by reinforcing connections between neighboring cells and weakening connections between distant cells. C: enlargement of B part including groups  et ‡ : Blue borders of weak connections protecting groups from encroachment by other groups. Interface /‡ corresponds to the frontier between palm and back of hand. J. Pearson et al., The J. of Neuroscience (1987)

27. Plasticity of hand functionalorganizationinduced by stimulation Receptive Fields of 3b neuronslocated on trained hand (monkeyswithimproved performances) 3b RFs on controlateral hand Recanzoneet al., J. of Neurophysiology (1992)

28. Hand functionalreorganization aftermedian nerve transsection 3b ///// : back of hand representation  : loss of response Median nerve transsection deprives the cortex of palm entries D1-D2 Stages of reorganization: Silence of some cortical regions; new responses in back D1-D3; (2) Almost complete recovery of reactivity. Buonomano & Merzenich, Annu. Rev. Neurosci., 21, (1998) / Merzenich et al., (1983).

29. 1. Cortical Maps: Plasticity of hand representations : 2. Cutaneous Receptive Fields: 1. A. areas 3b + 1 Parietal cortex. B normal topographic representation of hand in 3b. C. After median nerve transsection: loss of palm receptive fields + acquisition of back RF. 2. centers of palm receptive fields after nerve recovery (76j, 153j, 322j): re-innervation of median nerve territory: • RF unique (normal)○ RF multiple (anomalous). Wall et al., J.Neuro.(1986)

30. Maps of cutaneous receptive fields • after stimulation (normal/ abnormal) • A: before group formation • • cell responsive to palm stimuli • ○ cell responsive to dorsal stimuli • (mixed cells unmarked) • B: after formation of groups: • Most cells are of an exclusive type of response, mixed cells regrouping on the borders of network. • C: after repeated stimulation of one digit (X): • Expansion of representation of digit palm (x 13,7) detrimental to adjacent digits and back of same digit representations. • D: after transsection of median nerve : • Interruption of palm inputs of 2 digits safeguarding dorsal connections • invasion of dorsal representations in regions initially dedicated to palm representations • reactivity of some cells lost (black). J. Pearson et al., The J. of Neuroscience, 1987

31. Plan • “The complexity of reality”  • Complexity – a threat to the living being • Simplexity: getting us out of predicament • Natural science and phenomenology • Constitution Theory a framework for simplexity

32. Jackendoff: Projection Projected World Conceptual Structure ComputationalMind Gap Real World Information Petitot : Projection Projected World Phenomenological World • Conceptual Structure • ComputationalMind Pheno-physical Real World Information Geno-physical Real World Information

33. Schema of the dynamics of temporel field Transcendent Objects in objective Time Immanent Objects in phenomenologic time Things Processes Movements & durations ----------------- Preconstituted /Constituted ImpressionalConsciousness |Retentional Consciousness & Act (seizing the Now) | & Act (seizing the Now) ----------------------------------------------------------------------------------------- HyleticDatum[Now] Modification [ActualNow] Retention […[[[Ur-Jetzt]Jetzt]Jetzt]…letzte Jetzt] = [Ur-Jetzt], [[Ur-Jetzt]Jetzt], [[[Ur-Jetzt]Jetzt]Jetzt], … Originäre Zeitfeld: „Das Zeitfeld verschiebt sich gleichsam über die wahrgenommene und frisch erinnerte Bewegung und ihre objektive Zeit, ähnlich wie das Gesichtfeld über den objektiven Raum.“ (Vorlesungen über Zeitbewusstsein 1905 §.11)

34. Constitution d’objet temporel Rétention Impression originaire Saisie d’identité Recouvrement continu Passé Présent Distance temporelle Associations primaires présent présent présent présent Série des champs temporels Modification de passé présent « Cette saisie de présent est aux points de présent antérieurs comme le noyau à une queue de comète de rétentions. » présent Husserl, 1905. Positions dans le temps objectif

40. „…nur muss man beständig denken, dass, was wir schon so objektiviert finden, erst als dieses Objektivierte konstituiert ist durch die Sinngebung der Erfahrung; sie als die konkrete Erfahrung, durch die ich den vertrauten Leib als Leib immerzu erfahre, gibt ihm diesen Sinn durch die wohleingeübte Vermöglichkeit des wechselseitig Betastenkönnens, wobei sich das gesamte Empfindungsfeld in Lokalisation verteilt auf die „Glieder“ des Leibkörpers in ihrer Phantomkonstitution und dadurch auf den ganzen Körper…Nun ist aber jedes Organ einerseits durch betasten taktuell konstituiert und die dabei fungierenden Kinästhesen, andererseits aber selbst konstituiert als wirklich oder möglicherweise tastendes, sodass wir immer und notwendig in ursprünglichster Tasterfahrung, die den Leib als Körper und als Leib ergibt, ein funktionelles Beieinander von tastendem und getasteten Organ finden, und mit der jeweils vermöglichen Umkehrung dass das getastete zum tastenden werden kann…Dadurch sind also auch die Partialkinästhesen möglicher Betastung verteilt auf die Leibglieder, ein jedes ist nicht nur konstituiert als betastbar, sondern als betastend, als Glied mit Kinästhesen, die in Freiheit in Gang gebracht werden können…Ist diese volle Konstitution erreicht, so wird es verständlich, dass der Leib ohne Besehen und Betasten, während er ausschließlich für aussendingliche haptische Konstitution fungiert, immerfort doch ganz lebendig bewusst ist und in seiner haptischen Anschaulichkeit bewusst zu machen ist; nämlich dass das immerfort erfüllte und in sich zu durchlaufende Tastfeld sowie die fest auf es verteilten Kinästhesen beständig sein taktuelles „Aussehen“ indizieren. Bei aller sinnlicher Erfahrung, so zunächst der visuellen, ist irgend welches Hapsis mit dabei, und auch mein Leib als ursprünglich haptisch konstituierter mit dabei…“ [ms D12III (1931), p. 18-20]

41. Thank you!