Presentation is loading. Please wait.

Presentation is loading. Please wait.

Walter J Freeman University of California at Berkeley 1 Each new pattern of neural activity occupies the whole bulb. It reflects context, not information.

Similar presentations


Presentation on theme: "Walter J Freeman University of California at Berkeley 1 Each new pattern of neural activity occupies the whole bulb. It reflects context, not information."— Presentation transcript:

1 Walter J Freeman University of California at Berkeley 1 Each new pattern of neural activity occupies the whole bulb. It reflects context, not information. Spatial patterns of EEG

2 Walter J Freeman University of California at Berkeley 2 EEG pattern classification in serial conditioning: Heraclitus was right. Lack of invariance of brain patterns with fixed stimuli

3 Walter J Freeman University of California at Berkeley 3 Complex partial seizures disrupt normal behavior. Each inhalation opens the landscape. Expectancy creates attractor landscape. Flat EEG reflects a point attractor. Mexican hat From Skarda & Freeman (1987)

4 Walter J Freeman University of California at Berkeley 4 SDx(t) vs. A(t), ECoG

5 Walter J Freeman University of California at Berkeley 5 SDx(t) vs. A(t), Simulated

6 Walter J Freeman University of California at Berkeley 6 Brain evolution

7 Walter J Freeman University of California at Berkeley 7 St. Thomas Aquinas, Hume, Intentionality

8 Walter J Freeman University of California at Berkeley 8 Elizabeth called Descartes on the mind body problem

9 Walter J Freeman University of California at Berkeley 9 The origin of voluntary action

10 Walter J Freeman University of California at Berkeley 10 Helmholtz, army surgeon, neuroscientist, 1st law of thermodynamics

11 Walter J Freeman University of California at Berkeley 11 Charles Darwin 1809-1882 “The involuntary transmission of nerve-force may or may not be accompanied by consciousness. Why the irritation of nerve- cells should generate or liberate nerve- force is not known; but that this is the case seems to be the conclusion arrived at by all the greatest physiologists such as Müller, Virchow, Bernard, and so on.” The Expression of Emotions in Man and Animals (1863) p. 70

12 Walter J Freeman University of California at Berkeley 12 Herbert Spencer 1820-1903 Conservation of Nerve Energy It is “… an unquestionable truth that, at any moment, the existing quantity of liberated nerve-force, which in an inscrutable way produces in us the state we call feeling, must expend itself in some direction. … An overflow of nerve-force, undirected by any motive, will manifestly take the most habitual routes.” Essays: Scientific and Political (1893) p. 109

13 Walter J Freeman University of California at Berkeley 13 Sigmund Freud Displacement “[My] approach is derived from clinical observations of ‘excessively intense’ ideas in hysteria. … I have in mind the principle of neuronic inertia. It finds expression in a current passing from dendrites to axon. … Memory is in contacts between the neurons that function as barriers.” Sigmund Freud (1893) “The Project of a Scientific Psychology”, pp. 356-359. [Three years later, Foster and Sherrington named the ‘synapse’.]

14 Walter J Freeman University of California at Berkeley 14 Brain theory collapsed. _________________________________ ________ ___________________________ At the beginning of the 20th century, brain theory collapsed. Psychiatry and neurology disintegrated. The reason: ‘nerve energy’ is not conserved; brains are open, dissipative systems. Today there is still no accepted brain theory.

15 Walter J Freeman University of California at Berkeley 15 Gilbert Ryle - Category error _________________________________ ________ ___________________________

16 Walter J Freeman University of California at Berkeley 16 Kohler

17 Walter J Freeman University of California at Berkeley 17 Roger Sperry

18 Walter J Freeman University of California at Berkeley 18 The rise of information theory By the 1950s with the emergence of Computational Neural Science, the failed doctrine of “nerve energy” was replaced by the new doctrine of “neural information processing”. The power of the metaphor: Sources and sinks Information flow rates Channel capacities Information as Negentropy

19 Walter J Freeman University of California at Berkeley 19 Santiago Ramon y Cajal 1852-1934 Superior temporal gyrus Santiago Ramon y Cajal Information Technology begins in the neuron doctrine:

20 Walter J Freeman University of California at Berkeley 20 Rafael Lorente de Nó The theory of neural information processing was led by Cajal’s last graduate student, Lorente de Nó. Rafael Lorente de Nó 1901-1982 The Entorhinal Cortex, 1934 McCulloch & Pitts, 1945 Digital Computers, AI Donald Hebb, 1949 Nerve Cell Assemblies Frank Rosenblatt, 1956 Neural Networks Hubel and Wiesel, 1959 Neurobiology

21 Walter J Freeman University of California at Berkeley 21 Classic Thermodynamics, equilibrium

22 Walter J Freeman University of California at Berkeley 22 Self-organized criticality - compare to complex plane

23 Walter J Freeman University of California at Berkeley 23 Self-organized criticality - action perception cycle

24 Walter J Freeman University of California at Berkeley 24 Conclusion

25 Walter J Freeman University of California at Berkeley 25 “I have already explained what I think of literal representation; but one cannot insist enough on this: there is no true meaning of a text. No author’s authority. Whatever he may have wanted to say, he wrote what he wrote. Once published, a text is like an implement that everyone can use as he chooses and according to his means: it is not certain that the maker could use it better than someone else.” Collected Works, 1957 Paul Valéry Paul Valéry 1871-1945

26 Walter J Freeman University of California at Berkeley 26 Acknowledgements Acknowledgments This work was supported by grants from NIMH (MH-06686), ONR (N00014-93-1-09380, and NSF (EIA-0130352). Human EEG and EMG data were collected and edited by Mark D. Holmes and Sampsa Vanhatalo in the EEG Clinic, Harborview Hospital, University of Washington, Seattle, and analyzed in the Dep’t of Molecular & Cell Biology in the University of California at Berkeley. Data processing and programming were by Linda Rogers and Brian Burke. The animal data were collected in collaboration with John Barrie and Gyöngyi Gaál.


Download ppt "Walter J Freeman University of California at Berkeley 1 Each new pattern of neural activity occupies the whole bulb. It reflects context, not information."

Similar presentations


Ads by Google