1. What's in the brain that ink may character?1 What’s in the brain that ink may character? (Net-based models in neurology, cognition, and social processes) National Reading Conference, December 7, 2002. John E. McEneaney, Oakland University mceneane@oakland.edu mceneane@oakland.edu

2. What's in the brain that ink may character?2 Purpose of the presentation Historical/Conceptual Overview Logical Neurological Neuropsychological (from neurology to psychology) Psychoneurological (from psychology to neurology) Philosophical Issues What’s in the brain that ink may character? (Net-based models in neurology, cognition, and social processes)

3. What's in the brain that ink may character?3 Logical Foundations Established a systematic theoretical language for modeling complex systems Liebnitz & Boole: Algebraic Logic Frege & Russell: Propositional logic von Neumann: Computational logic

4. What's in the brain that ink may character?4 Ramon y Cajal (1889): independence of nerve cells Lloyd (1941): inhibitory synapses demonstrated McCulloch & Pitts (1943): A logical calculus … Penfield & Rasmussen (1957): motor & sensory map Lettvin, Maturana, M & P (1959): What the frog’s eye … Neurological Foundations Established fundamental principles governing neural systems

5. What's in the brain that ink may character?5 Pitts, W. & McCulloch, W. (1947). How we know universals, The perception of auditory and visual forms. In Warren S. McCulloch (Ed.), Embodiments of Mind, p. 53. Cambridge: MIT Press.

6. What's in the brain that ink may character?6 Pitts, W. & McCulloch, W. (1947). How we know universals, The perception of auditory and visual forms. In Warren S. McCulloch (Ed.), Embodiments of Mind, p. 53. Cambridge: MIT Press.

7. What's in the brain that ink may character?7 Pitts, W. & McCulloch, W. (1947). How we know universals, The perception of auditory and visual forms. In Warren S. McCulloch (Ed.), Embodiments of Mind, p. 53. Cambridge: MIT Press.

8. What's in the brain that ink may character?8 The Motor Homunculus Cortical regions and the motor functions they support. But localization is not limited to motor functions. Cognitive functions and even specific memories may be local.

9. What's in the brain that ink may character?9 Lettvin, Maturana, McCulloch, & Pitts (1959). What the frog’s eye tells the frog’s brain. In Warren S. McCulloch (Ed.), Embodiments of Mind, pp. 230-255. Cambridge: MIT Press. What the frog’s eye tells the frog’s brain “There are four types of fibers, each type concerned with a different sort of pattern. Each type is uniformly distributed over the whole retina of the frog. Thus, there are four distinct parallel distributed channels …” (my emphasis) 1. Local edges & contrast 2. Curved edges of dark objects 3. Edge movement 4. Dimming due to movement or rapid general darkening

10. What's in the brain that ink may character?10 Minsky, M. L. & Papert, S. A. (1988). Perceptrons, p. 144. Cambridge: MIT Press. From Neurology to Psychology Generalizations from neurology are applied in developing psychological theory and models Rosenblatt (1962): Principles of neurodynamics. Minsky & Papert (1969): Perceptrons McClelland and Rumelhart (1981): IA model McClelland and Rumelhart (1986): PDP Volumes Seidenberg (1992): Simulating phonological dyslexia Plaut & Shallice (1993): Simulating deep dyslexia McEneaney (1994): Simulating developmental dyslexia

11. What's in the brain that ink may character?11 Minsky, M. L. & Papert, S. A. (1988). Perceptrons, p. 5. Cambridge: MIT Press. Rosenblatt, F. (1958). The perceptron-a theory of statistical separability in cognitive systems. Cornell Aeronautical Laboratory Inc., Report No. VG-1196-G-1. Rosenblatt, F. (1962). Principles of neurodynamics. New York: Spartan. Perceptrons as pattern recognition devices

12. What's in the brain that ink may character?12 Minsky, M. L. & Papert, S. A. (1988). Perceptrons, p. 206. Cambridge: MIT Press. Introduction of multi-layer systems

13. What's in the brain that ink may character?13 McClelland, J. L. & Rumelhart, D. E. (1981). An interactive activation model of context effects in letter perception: Part 1. An account of basic findings. Psychological Review, 88, 375-407. The Interactive Activation Model of Word Recognition Multi-layer perceptrons re-emerge as PDP models

14. What's in the brain that ink may character?14 Architecture of the IA model

15. What's in the brain that ink may character?15 The problem of levels in PDP models Microstructure versus Macrostructure

16. What's in the brain that ink may character?16 Hinton, G. E. & Shallice, T. (1991). Lesioning an attractor network: Investigations of acquired dyslexia. Psychologiucal Review, 98, 74-95. Plaut, D. C. & Shallice, T. (1993). Deep dyslexia: A case study of connectionist neuropsychology. Cognitive Neuropsychology, 10(5), 377-500. Architecture of the Hinton & Shallice Model

17. What's in the brain that ink may character?17 From Psychology to Neurology (by way of medical imaging technology) Generalizations from psychology are applied in developing neurological theory and models Angiography: dye injection reveals blood vessels Electro-encephalography (EEG): reveals natural electrical activity Computerized Tomography (CT/CAT): X-rays, reveals structure Positron Emission Tomography (PET): radioactive decay, reveals activity Magnetic Resonance Imaging (MRI): induced emissions, shows structure CT/CATPET MRI PET + MRI

18. What's in the brain that ink may character?18 Distinguishing Dylexic and Normal Brains

19. What's in the brain that ink may character?19 Some Closing Questions Are there fundamental epistemological limits on a brain’s knowledge of itself? Are levels of description appropriate in biological and cognitive phenomena fundamentally incompatible? How should and/or could knowledge about brain function inform teaching? “I expect that the future art of brain design will have to be more like sculpturing than like our present craft of programming.” Marvin Minsky (1991)