1 Introduction |
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1.1 What is computational neuroscience? |
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1.1.1 Tools and specializations in neuroscience |
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1.1.2 Levels of organization in the brain |
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1.2.1 Phenomenological and explanatory models |
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1.2.2 Models in computational neuroscience |
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1.3 Is there a brain theory? |
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1.3.1 Emergence and adaptation |
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1.4 A computational theory of the brain |
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1.4.1 Why do we have brains? |
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1.4.2 The anticipating brain |
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I Basic neurons |
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2 Neurons and conductance-based models |
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2.1 Biological background |
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2.1.1 Structural properties |
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2.1.2 Information-processing mechanisms |
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2.2 Basic synaptic mechanisms and dendritic processing |
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2.2.1 Chemical synapses and neurotransmitters |
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2.2.2 Excitatory and inhibitory synapses |
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2.2.3 Modelling synaptic responses |
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2.2.4 Non-linear superposition of PSPs |
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2.3 The generation of action potentials: HodgkinHuxley equations |
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2.3.1 The minimal mechanisms |
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2.3.3 HodgkinHuxley equations |
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2.3.4 Numerical integration |
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2.3.6 Propagation of action potentials |
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2.3.7 Above and beyond the HodgkinHuxley neuron: the Wilson model o |
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2.4 Including neuronal morphologies: compartmental models |
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2.4.2 Physical shape of neurons |
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3 Simplified neuron and population models |
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3.1 Basic spiking neurons |
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3.1.1 The leaky integrate-and-fire neuron |
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3.1.2 Response of IF neurons to very short and constant input currents |
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3.1.3 Activation function |
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3.1.4 The spike-response model |
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3.1.5 The Izhikevich neuron |
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3.1.6 The McCullochPitts neuron |
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3.2 Spike-time variability o |
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3.2.1 Biological irregularities |
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3.2.2 Noise models for IF neurons |
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3.2.3 Simulating the variability of real neurons |
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3.2.4 The activation function depends on input |
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3.3 The neural code and the firing rate hypothesis |
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3.3.1 Correlation codes and coincidence detectors |
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3.3.2 How accurate is spike timing? |
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3.4 Population dynamics: modelling the average behaviour of neurons |
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3.4.1 Firing rates and population averages |
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3.4.2 Population dynamics for slow varying input |
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3.4.3 Motivations for population dynamics o |
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3.4.4 Rapid response of populations |
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3.4.5 Common activation functions |
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3.5 Networks with non-classical synapses: the sigmapi node |
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3.5.1 Logical AND and sigmapi nodes |
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3.5.2 Divisive inhibition |
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3.5.3 Further sources of modulatory effects between synaptic inputs |
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4 Associators and synaptic plasticity |
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4.1 Associative memory and Hebbian learning |
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4.1.3 Hebbian learning in the conditioning framework |
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4.1.4 Features of associators and Hebbian learning |
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4.2 The physiology and biophysics of synaptic plasticity |
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4.2.1 Typical plasticity experiments |
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4.2.2 Spike timing dependent plasticity |
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4.2.3 The calcium hypothesis and modelling chemical pathways |
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4.3 Mathematical formulation of Hebbian plasticity |
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4.3.1 Spike timing dependent plasticity rules |
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4.3.2 Hebbian learning in population and rate models |
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4.3.3 Negative weights and crossing synapses |
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4.4 Synaptic scaling and weight distributions |
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4.4.1 Examples of STDP with spiking neurons |
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4.4.2 Weight distributions in rate models |
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4.4.3 Competitive synaptic scaling and weight decay |
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4.4.4 Oja's rule and principal component analysis |
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II Basic networks |
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5 Cortical organization and simple networks |
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5.1 Organization in the brain |
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5.1.1 Large-scale brain anatomy |
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5.1.2 Hierarchical organization of cortex |
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5.1.3 Rapid data transmission in the brain |
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5.1.4 The layered structure of neocortex |
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5.1.5 Columnar organization and cortical modules |
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5.1.6 Connectivity between neocortical layers |
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5.1.7 Cortical parameters |
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5.2 Information transmission in random networks o |
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5.2.2 Divergingconverging chains |
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5.2.3 Immunity of random networks to spontaneous background activity |
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5.2.5 Information transmission in large random networks |
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5.2.6 The spread of activity in small random networks |
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5.2.7 The expected number of active neurons in netlets |
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5.2.8 Netlets with inhibition |
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5.3 More physiological spiking networks |
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5.3.2 Networks with STDP and polychrony |
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6 Feed-forward mapping networks |
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6.1 The simple perceptron |
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6.1.1 Optical character recognition (OCR) |
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6.1.3 The population node as perceptron |
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6.1.4 Boolean functions: the threshold node |
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6.1.5 Learning: the delta rule |
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6.2 The multilayer perceptron |
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6.2.1 The update rule for multilayer perceptrons |
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6.2.3 The generalized delta rules |
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6.2.4 Biological plausibility of MLPs |
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6.3 Advanced MLP concepts o |
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6.3.1 Kernel machines and radial-basis function networks |
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6.3.3 Batch versus online algorithm |
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6.3.4 Self-organizing network architectures and genetic algorithms |
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6.3.5 Mapping networks with context units |
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6.3.6 Probabilistic mapping networks |
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6.4 Support vector machines o |
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6.4.1 Large-margin classifiers |
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6.4.2 Soft-margin classifiers and the kernel trick |
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7 Cortical feature maps and competitive population coding |
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7.1 Competitive feature representations in cortical tissue |
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7.2.1 The basic cortical map model |
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7.2.3 Ongoing refinements of cortical maps |
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7.3 Dynamic neural field theory |
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7.3.1 The centre-surround interaction kernel |
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7.3.2 Asymptotic states and the dynamics of neural fields |
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7.3.3 Examples of competitive representations in the brain |
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7.3.4 Formal analysis of attractor states o |
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7.4 Path' integration and the Hebbian trace rule o |
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7.4.1 Path integration with asymmetrical weight kernels |
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7.4.2 Self-organization of a rotation network |
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7.4.3 Updating the network after learning |
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7.5 Distributed representation and population coding |
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7.5.2 Probabilistic population coding |
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7.5.3 Optimal decoding with tuning curves |
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7.5.4 Implementations of decoding mechanisms |
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8 Recurrent associative networks and episodic memory |
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8.1 The auto-associative network and the hippocampus |
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8.1.1 Different memory types |
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8.1.2 The hippocampus and episodic memory |
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8.1.3 Learning and retrieval phase |
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8.2 Point-attractor neural networks (ANN) |
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8.2.1 Network dynamics and training |
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8.2.2 Signal-to-noise analysis o |
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8.2.4 Spurious states and the advantage of noise |
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8.2.5 Noisy weights and diluted attractor networks |
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8.3 Sparse attractor networks and correlated patterns |
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8.3.1 Sparse patterns and expansion recoding |
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8.3.2 Control of sparseness in attractor networks |
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8.4 Chaotic networks: a dynamic systems view |
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8.4.3 The Cohen-Grossberg theorem |
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8.4.4 Asymmetrical networks |
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8.4.5 Non-monotonic networks |
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III System-level models |
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9 Modular networks, motor control, and reinforcement learning |
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9.1 Modular mapping networks |
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9.1.2 The 'what-and-where' task |
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9.2 Coupled attractor networks |
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9.2.1 Imprinted and composite patterns |
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9.2.2 Signal-to-noise analysis |
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9.4 Complementary memory systems |
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9.4.1 Distributed model of working memory |
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9.4.2 Limited capacity of working memory |
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9.4.3 The spurious synchronization hypothesis |
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9.4.4 The interacting-reverberating-memory hypothesis |
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9.5 Motor learning and control |
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9.5.1 Feedback controller |
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9.5.2 Forward and inverse model controller |
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9.5.3 The cerebellum and motor control |
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9.6 Reinforcement learning |
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9.6.1 Classical conditioning and the reinforcement learning problem |
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9.6.2 Temporal delta rule |
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9.6.3 Temporal difference learning |
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9.6.4 The actorcritic scheme and the basal ganglia |
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10.1 Hierarchical maps and attentive vision |
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10.1.1 Invariant object recognition |
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10.1.3 Attentional bias in visual search and object recognition |
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10.2 An interconnecting workspace hypothesis |
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10.2.1 The global workspace |
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10.2.2 Demonstration of the global workspace in the Stroop task |
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10.3 The anticipating brain |
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10.3.1 The brain as anticipatory system in a probabilistic framework |
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10.3.2 The Boltzmann machine |
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10.3.3 The restricted Boltzmann machine and contrastive Hebbian learning |
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10.3.4 The Helmholtz machine |
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10.3.5 Probabilistic reasoning: causal models and Bayesian networks |
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10.3.6 Expectation maximization |
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10.4 Adaptive resonance theory |
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10.4.3 Simplified dynamics for unsupervised letter clustering |
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10.5 Where to go from here |
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A Some useful mathematics |
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A.1 Vector and matrix notations |
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B Numerical calculus |
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B.2 Numerical integration of an initial value problem |
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C Basic probability theory |
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C.1 Random numbers and their probability (density) function |
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C.2 Moments: mean, variance, etc. |
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C.3 Examples of probability (density) functions |
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C.3.1 Bernoulli distribution |
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C.3.2 Binomial distribution |
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C.3.3 Chi-square distribution |
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C.3.4 Exponential distribution |
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C.3.5 Lognormal distribution |
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C.3.6 Multinomial distribution |
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C.3.7 Normal (Gaussian) distribution |
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C.3.8 Poisson distribution |
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C.3.9 Uniform distribution |
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C.4 Cumulative probability (density) function and the Gaussian error function |
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C.5 Functions of random variables and the central limit theorem |
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C.6 Measuring the difference between distributions |
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C.6.1 Marginal, joined, and conditional distributions |
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D Basic information theory |
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D.1 Communication channel and information gain |
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D.2 Entropy, the average information gain |
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D.2.1 Difficulties in measuring entropy |
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D.2.2 Entropy of a spike train with temporal coding |
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D.2.3 Entropy of a rate code |
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D.3 Mutual information and channel capacity |
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D.4 Information and sparseness in the inferior-temporal cortex |
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D.4.1 Population information |
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D.4.2 Sparseness of object representations |
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E A brief introduction to MATLAB |
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E.1 The MATLAB programming environment |
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E.1.1 Starting a MATLAB session |
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E.1.2 Basic variables in MATLAB |
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E.1.3 Control flow and conditional operations |
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E.1.4 Creating MATLAB programs |
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E.2 A first project: modelling the world |
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