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Neuroscience & Karma
to its ending in contact with yet another nerve-cell, or with a muscle or gland. This process of summation of the effects of the boutons is thus the means by which decisions are reached in the nervous system. 5. Decoding
The signals arriving in various combinations along the sensory nerve-fibres will activate particular nerve cells. The first stage of what may be called the decoding of the signals in a set of nerve-fibres is by the activation of certain particular cells of the brain by the synapses.
The basic outlines of the patterns of connection are laid down by heredity. These are our pre-program, such as that for breathing. Nearly all of our activities include a part that is hereditary and can be referred to as instinctive. Much more interesting is the question of how these basic patterns come to be combined with other patterns of action of the nervecells by the process of learning. This is how we acquire language and the socially transmitted programs that dominate so much of our lives. Even more interesting is the question of how new programs can arise within us, as they certainly do, if we are even minimally creative. These are some of the problems that we hope to face later. However, decoding does not mean that there is somet
re is some final stage where the message is understood. The decoding is completed only by action or preparation for action.
It should not however be concluded that we are activated only by external stimuli. In fact, many of the nerve-cells go through continual cycles of activity or changes in sensitivity. The effect of incoming impulses is then to alter their frequency of discharge. Whole sections of the nervous system never cease their activities. To take the simplest example, the cells of the respiratory centres send out nerve-impulses regularly every few seconds to the muscles of the chest, from our first breath to our last. Some of these rhythms are due to inherent properties of the membranes of the cells. Others are the result of cyclical chains of nerve-cells, so arranged that they continually re-excite each other. Our behaviour, thus, comes from the combined operations of this vast set of internal rhythms with the inflow of information from the sense organs.
