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Neuroscience & Karma
patterns Perception is an active search for meaningful clues and the brain builds programs that guide the search. These programs may possibly be something like those that artificial intelligence workers devise for pattern recognition with computers. Perception involves ina king structural descriptions from the data and testing interferences as to what these data mean for us. The brain presumably bas programs for examining features such as brightness, corners, edges and so on, in order to find, first points, then lines, regions, surfaces, bodies, and eventually objects that have meaning or use. The brain reads the letters, words, sentences, and paragraphs of the visual code. The optic nerves carry the information to at least three parts of the brain, the midbrain, cerebellum, and through the thalamus to the cortex. All these parts are interconnected and concerned in any act of vision, but the first two deal mainly with detailed control of the eye movements. Deeper in the centre of the midbrain are motor nerve-cells, each of which has its own 'movement area' so that it sends signals when there is movement in a particular part of the visual field. So, in a general way, we can say that ibe projection from the eye to the mid-brain is concerned with 'where to look, while the cerebral cortex determines 'what to look at.
The primary visual cortex is in the occipital region at the back of the head. Here the pattern of the retina is enormously enlarged, with 5000 cortical cells for each celi of the thalamus.
As signals from the retina pass through the various visual areas they are recombined in different ways. This is the process by which the words of the brain are joined in'grammatical' ways to give meanings. No doubt, there are hereditary and karmic elements in the development of the granunar and it is also greatly influenced by experience.
in the later stages of decoding, each pan of the system ---retina, cells of the thaiamus, the primary visual cortex ---progressively extracts more and more abstract or general features of the visual information. The process does not continue uninterruptedly for vision, or any other sense. The whole set of brain actions goes on in discrete packages, each of perhaps one-fifth of a second. Our own awareness of the stream of consciousness suggests that there is some central processor receiving
