Sensory Substitution & Plasticity

Neat article in today’s NYT on how a tongue stimulator can re-route many different sensory modalities. The most dramatic example (which the article focuses on) is how the device helps rehabilitate a patient with extensive vestibular damage and trains her brain to use whatever vestibular neurons she has left by this alternative (somatosensory) pathway. Click below for the full article.
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Neural networks at your fingertips

This website has short, free, open-source C implementations of 8 kinds of neural networks:

  • Adaline Network
  • Backpropagation Network
  • Hopfield Model
  • Bidirectional Associative Memory
  • Boltzmann Machine
  • Counterpropagation Network
  • Self-Organizing Map
  • Adaptive Resonance Theory

    doing 8 kinds of tasks:

  • Classification of Digits 0-9
  • Prediction of the Annual Number of Sunspots
  • Associative Recall of Images
  • Association of Names and Phone Numbers
  • Traveling Salesman Problem
  • Determination of the Angle of Rotation
  • Pole Balancing Problem
  • Stability-Plasticity Demonstration
  • The symbol grounding problem and recurrent neural networks with parametric biases

    The symbol grounding problem (apparently) is: assuming that someone’s “cognitive” levels of mind work in terms of symbols, how to design the interface of the symbolic levels with the low-level sensory-motor systems?

    Jun Tani suggests a “recurrent neural network with parametric biases” (RNNPB).

    I haven’t had time to read further yet, but it looks very interesting so I’m passing it along now lest it get lost. When I get around to it I’ll post an update that summarizes what RNNPBs are and precisely how they interface symbol computation with lower-level systems. I may attend the talk (which is tomorrow).

    Read on for an abstract from Jun Tani’s talk.
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