Physiological mechanisms of viscerosensory events have been analyzed in detail, beginning with the pioneering discovery of the depressor nerve activity originating from the aortic arch by Cyon and Ludwig (1866). But in our thinking, the viscerosensory system is still not regarded as a special integrated entity of sensory physiology. This circumstance has been vigorously advocated in my papers (e.g., Ádám, 1974, 1978) going back to the monograph published in 1967. But the situation has not changed since then. The causes and the current theoretical trends are discussed else where in this book (see pp. 119–122). In this chapter, I raise this issue in order to set in its proper light the intention to make clear the functions of visceral afferent messages. The first of these relates to their adequate stimuli in their environment (i.e., mechanical, chemical, osmotic, thermal, and so on) in the framework of which they exert their primary impact on the normal functioning of the organism. The nature of the physical and chemical agents exercising influence on visceral afferent endings determines primarily the activity of their own receptive structures and only secondarily the physiological systems in which they act. In other words, the basic principles of activity of mechanical or chemical receptor organs are identical (or at least similar) regardless of whether they function in the framework of the alimentary or the circulatory systems. This evidence is clear to those working in the field of viscerosensory mechanisms, although, to my knowledge, only a few major comprehensive studies have been published in the last two decades integrating viscerosensory processes detaching them from their organ systems (Newman, 1974; Mei, 1983; Cervero & Morrison, 1986).
KeywordsAortic Arch Receptive Field Stellate Ganglion Afferent Pathway Glossopharyngeal Nerve
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