A Thousand Brains: A New Theory of Intelligence

by Jeff Hawkins

We started with the idea that the neocortex learns a rich and detailed model of the world, which it uses to constantly predict what its next sensory inputs will be. We then asked how neurons can make these predictions. This led us to a new theory that most predictions are represented by dendrite spikes that temporarily change the voltage inside a neuron and make a neuron fire a little bit sooner than it would otherwise. Predictions are not sent along the cell’s axon to other neurons, which explains why we are unaware of most of them. We then showed how circuits in the neocortex that use the new neuron model can learn and predict sequences. We applied this idea to the question of how such a circuit could predict the next sensory input when the inputs are changing due to our own movements. To make these sensory-motor predictions, we deduced that each cortical column must know the location of its input relative to the object being sensed. To do that, a cortical column requires a reference frame that is fixed to the object.