Self Comes to Mind

basic ingredients in the construction of conscious minds are wakefulness and images . On the matter of wakefulness , we know that it depends on the operation of certain nuclei in the brain-stem tegmentum and the hypothalamus. Using both neural and chemical routes, these nuclei exert their influence on the cerebral cortex. As a result, vigilance is either diminished (producing sleep) or enhanced (producing wakefulness). The work of the brain-stem nuclei is assisted by the thalamus, although some nuclei influence the cerebral cortex directly; as for the hypothalamic nuclei, they operate largely by release of chemical molecules that subsequently act on neural circuits and alter their behavior.
    The delicate balance of wakefulness depends on the close interplay of hypothalamus, brain stem, and cerebral cortex. The function of the hypothalamus is closely related to the amount of light available, the part of the wakefulness process whose disruption causes jet lag when we fly across several time zones. In turn, this operation is closely coupled with hormonal secretion patterns tied in part to day-night cycles. The hypothalamic nuclei control the operation of endocrine glands throughout the organism—pituitary, thyroid, adrenals, pancreas, testes, ovaries. 4
    The brain-stem component of the wakefulness process relates to the natural value of each ongoing situation. Spontaneously and nonconsciously, the brain stem answers questions that no one poses, such as, how much should the situation matter to the beholder? Value determines the signal and degree of emotional responses to a situation as well as how awake and alert we are to be. Boredom plays havoc with wakefulness, but so do metabolic levels. We know what happens during digestion of a large meal, especially if certain chemical ingredients are present such as tryptophan, which is released from red meats. Alcohol increases wakefulness at first, only to induce sleepiness later, as blood alcohol levels rise. Anesthetics suspend wakefulness altogether.
    One last cautionary note regarding wakefulness: the sector of the brain stem involved in wakefulness is distinct, in terms of its neuroanatomy and neurophysiology, from the sector of the brain stem that generates the foundations of the self, the protoself (which is discussed in the next section). The brain-stem wakefulness nuclei are anatomically close to the brain-stem protoself nuclei for a very good reason: both sets of nuclei participate in life regulation. However, they contribute to the regulatory process in different ways. 5
    On the matter of images , it may seem that we already know what we need to know, given that we discussed their neural basis in Chapters 3 through 6. But we need to say more. Images are certainly the source of the objects-to-be-known in the conscious mind, whether the objects are out in the world (external to the body) or inside the body (like my painful elbow or the finger you burned inadvertently). Images come in all sensory varieties, not just visual, and they pertain to any object or action being processed in the brain , actually present or being recalled, concrete as well as abstract. This covers all patterns originating outside the brain , either inside or external to the body. It also covers patterns generated inside the brain as a result of conjunctions of other patterns. Indeed, the brain’s ravenous map-making addiction leads it to map its own workings—once again, talk to itself. The brain’s maps of its own doings are probably the main source of abstract images that describe, for example, spatial placements and movement of objects, relationships of objects, velocity and spatial course of objects in motion, and patterns of occurrence of objects in time and space. These sorts of images can be converted into mathematical descriptions as well as musical compositions and executions. Mathematicians and composers excel at this sort of image-making.
    The working hypothesis advanced earlier proposes that conscious minds arise from establishing a relationship between the organism and an object-to-be-known . But how are the organism and the object and the relationship implemented in the brain? All three components are made of images. The object to be known is mapped as an image. So is the organism, although its images are special. As for the knowledge that constitutes a self state and permits the emergence of subjectivity, it too is made of images. The entire fabric of a conscious mind is