Alphabetical list
FMC rules and notationsbrowse by initial: A B C D E F G H I L M N O P R S T U V W
Sagittal plane ( Henle, 1855 ) : In animals with bilateral symmetry, the plane of section parallel to the longitudinal axis (Barclay, 1803) of the body and passing dorsal (Barclay, 1803)-ventral (Schulze, 1893), orthogonal to the other longitudinal plane (Henle, 1855), the frontal plane (Henle, 1855). Term introduced by Henle (1855, p. 2), also see Kuhlenbeck (1973, p. 114). more details
Schematic diagram : An illustration of the arrangement of connections that is more abstract than a wiring diagram because it is concerned more with topological than with physical relationships; see Wikipedia (Schematic diagram). more details
Secondary hindbrain ( Sharpey et al., 1867 ) : Synonym for hindbrain (Baer, 1837); p. 577. Also used by for example Strong & Elwyn (1943, p. 13). more details
Site : An arbitrarily defined point, area, or volume in the nervous system (Monro, 1783) that may or may not correspond to a standard structural feature (term); examples include injection site, labeling site, lesion site, stimulation site, activation site, and sampling site. A site encompasses a neuron population (Burns, 2001). more details
Soma : Synonym for cell body (Deiters, 1865); see Peters et al. (1991, p. 14). more details
Somata : Pleural of soma. more details
Somatic spine : The equivalent of a dendritic spine on a neuron cell body (Deiters, 1865), the soma; see Swanson (1976a, p. 54). more details
Spinal bulb ( Chaussier, 1807 ) : Synonym for medulla (Winslow, 1733); introduced for macrodissected adult humans by Chaussier (1807, p. 120). more details
Spinal cord ( SP ; Galen, c162-c176 ) : The caudal (Cleland, 1879) topographic division of the cerebrospinal axis (Meckel, 1817); the rostral (Schulze, 1893) topographic division is the vertebrate brain (Cuvier, 1800). The usual criterion for distinguishing the two divisions in the adult is that the vertebrate brain lies within the skull whereas the spinal cord lies within the spinal (vertebral) column, although this is a difficult problem in practice; see Crosby et al. (1962, pp. 112-120). Definite knowledge of the spinal cord dates to Hippocrates in Fleshes (see translation by Potter, 1995, p. 139), and Galen (c162-c176) used the term specifically-see translation by De Lacy (1978, p. 85). Common synonyms include medulla spinalis (Hippocrates), or spinal medulla in English, and spinal marrow (Bannister, 1578). more details
Spinal marrow ( Bannister, 1578 ) : English form of medulla spinalis (Hippocrates); see Bannister (1578, f. 106v). more details
Spinal marrow ( Varolio, 1573 ) : Term included the spinal cord (Galen, c162-c166), medulla (Winslow, 1733), pons (Haller, 1747), and midbrain (Baer, 1837) for macrodissected adult humans; Fig. 2(1-3) on f. 19r. more details
Spinal marrow ( Vesalius, 1543 ) : Term included the spinal cord (Galen, c162-c166), medulla (Winslow, 1733), and pons (Haller, 1747) of macrodissected adult humans; see translation by Richardson & Carman (2002, p. 222). more details
Spinal medulla : English form of medulla spinalis (Hippocrates); see translations by May (1968, p. 575), Adams (1972, pp. 234, 309), and Potter (1995, p. 139). more details
Spinal nerve ganglia ( GS ; Burdach, 1819 ) : The topographic division consisting of sensory ganglia (Galen, c173) associated with the dorsal roots of the spinal nerve roots (Tiedemann, 1816), divided into cervical spinal ganglia, thoracic spinal ganglia, lumbar spinal ganglia, and coccygeal spinal ganglia. They were discovered in macrodissected adult humans by Coiter (1572, see translation, 1995, pp. 113-115) and named thus by Burdach (1819, vol. 1, p. 136). more details
Spinal nerve plexuses ( plxs ; Galen (c192) ) : A network of communicating branches (Winslow, 1733) between three or more spinal nerves (Camper, 1760); examples are the cervical plexus (Molinetti, 1675), brachial plexus (Camper, 1760), lumbar plexus (Vesalius, 1543), and sacral plexus (Vesalius, 1543). These plexuses (Galen, c192) were identified in macrodissected adult animals except humans in the second century by Galen; see translations of Duckworth (1962, pp. 230-264) and May (1968, pp. 598-603). more details
Spinal nerve primary branches ( spb ; Galen (c192) ) : In general, each spinal nerve trunk divides distally into a spinal nerve dorsal branch (Meckel, 1817) and a spinal nerve ventral branch; this arrangement was identified in macrodissected adult animals except humans in the second century by Galen; see translations by Duckworth (1962, p. 229 ff.) and May (1968, pp. 597-599); for contemporary terminology see Durward (1951, p. 1052 and Fig. 913). more details
Spinal nerve roots ( srt ; Tiedemann, 1816 ) : In general, each of the spinal nerves (Camper, 1760) has a peripheral dorsal root and ventral root between the surface of the spinal cord (Galen, c162-c166) and the plane where they merge into a composite spinal nerve trunk. The spinal nerve roots were discovered in macrodissected adult humans by Coiter (1572, see translation of 1995, p. 115); they were named such by Tiedemann (1816, see translation of 1826, p. 126). more details
Spinal nerve trunk ( spt ; Winslow, 1733 ) : The short segment of a spinal nerve (Camper, 1760) between the junction of the dorsal root and ventral root, and the origin of the spinal nerve primary branches; this arrangement was specifically described for macrodissected adult humans by Winslow (1733, Sect. VI, p. 76); for contemporary terminology see Durward (1951, Fig. 913). more details
Spinal nerves ( spin ; Camper, 1760 ) : The topographic division of vertebrate craniospinal nerves (Herrick, 1915)-the other being cranial nerves (Longet, 1742)-that arises from the spinal cord (Galen, c162-c166) and exits the vertebral or spinal column, and is also distinguished from autonomic nerves (Langley, 1898). They are divided into groups of cervical nerves (Galen, c173), thoracic nerves (Diemerbroeck, 1672), lumbar nerves (Diemerbroeck, 1672), sacral nerves (Camper, 1760), and coccygeal nerves (Camper, 1762), as enumerated now for macrodissected adult humans. Most of them were known to Herophilus (335-280 BC), the founder of human anatomy (see Solmsen, 1961; von Staden, 1989), and the term itself was first used in the currently accepted way for macrodissected adult humans by Camper (1760). The synonym vertebral nerves (Willis, 1664) might be a more accurate match for cranial nerves (Longet, 1742). more details
Spine ( Cajal, 1888 ) : Short form of dendritic spine (Cajal, 1899), or somatic spine; p. 4, "espinas" in Spanish. It may of course also refer to the spinal (vertebral) column. more details
Standard term : A defined term that is chosen from a list of synonyms to represent a concept in the Foundational Model of Connectivity; reference term is a nonpreferred synonym. more details
Structural connection : A long form of connection. more details
Subarachnoid space ( Magendie, 1827 ) : The part of the ventricular-subarachnoid space that lies between the outer and inner layers of meninges (Edwin Smith Surgical Papyrus, c1700 BC), the dura (Galen, c177) and pia (Galen, c192), respectively; it is continuous with the ventricles (Hippocrates) and is filled with cerebrospinal fluid. The existence of fluid under the dura, in what is now called the subarachnoid space, was known to Hippocrates (see Millen & Woollam, 1962, p. 1), and named by Magendie (1827, pp. 21, 25) in a variety of macrodissected mammals. more details
Subsystems arrangement of gray matter regions : An essentially neural network arrangement of gray matter regions based on functional subsystems. Swanson (2004, Table B) provided a systematic example for a 4-subsystem network model of rat central nervous system (Meckel, 1817) organization. more details
Subsystems microarchitecture of nervous system ( Swanson & Bota (2010) ) : One of two common orthogonal ways to describe completely the nervous system (Monro, 1873). Subsystems here deal with the accurate microscopic (histological) delineation and description of gray matter regions and white matter tracts, in contrast to the topographic description of nervous system that deals with macroscopic locations in the nervous system. For the nervous system (Monro, 1783), connections and the routes they take are described in terms of gray matter regions and white matter tracts, which are formed by neuron types (Bota & Swanson, 2007), neuron parts, and molecules. An individual nervous system subsystem is a set of connections that form a complex unity with a specific function; also see systems description of body. more details
Superficial ( Galen, c173 ) : A relationship between adjacent objects in the body; an object is superficial to another when it is closer to the surface; the opposite of deep. The dichotomy has been used at least since the second century by Galen; see translation by May (1968, p. 715), also see Standring (2008, p. xxii). more details
Superior ( Vicq d'Azyr, 1786 ) : He defined it as above or toward the head in human anatomy; pp. 51, 116; also see Standring (2008, p. xxii) and anterior (Aristotle). more details
Supporting structures of nervous system ( Swanson & Bota, 2010 ) : Topographic macrostructure features that include the connective tissue coverings of the nervous system (Monro, 17893)-the meninges (Edwin Smith Surgical Papyrus, c1700 BC)-and the compartment within and surrounding the nervous system that is filled with cerebrospinal fluid (CSF; in ventricles-subarachnoid space); see Millen & Woollam (1962). It is important to consider that the circulatory system pervades the nervous system. more details
Supraesophageal ganglion ( Swanson & Bota, 2010 ) : Invertebrate brain that lies dorsal (Barclay, 1803) to the digestive system in annelids and arthropods. One or more supraesophageal ganglia may be involved, depending on how many central nerve cords there are in a species; see Bullock & Horridge (1965, pp. 662, 1609), Reisinger (1972), and ventral ganglia. more details
Synapse ( Foster & Sherrington, 1897 ) : Generally, a natural junction achieving functional conduction between distinct neurons (Waldeyer, 1891), or a neuron and another cell (Hooke, 1665), and accomplished through contact or near contact without regard to mechanism; see Bullock & Horridge (1965, pp. 181, 196). They are usually divided into chemical synapses, electrical synapses, and mixed synapses. The most common in adult vertebrates, the chemical synapse, is a structure-function differentiation consisting of three parts: a neuronal presynaptic compartment (De Camilli et al., 2001) where neurotransmitter is released from the terminal (Cajal, 1899), a synaptic cleft of variable width, and a postsynaptic compartment (De Camilli et al., 2001) that may or may not be neuronal but does have plasma membrane receptors for neurotransmitters. At classical unidirectional chemical synapses neurotransmitters may have feedforward effects on the postsynaptic membranes and feedback effects on presynaptic membranes. It is thought, however, that these synapses are rectifiers, with neural network information flowing from presynaptic neuron to postsynaptic cell, modulated by presynaptic neurotransmitter feedback. In contrast, reciprocal or bidirectional chemical synapses release neurotransmitter on both sides of the synaptic cleft and can thus transmit neural network information in either direction depending on network activity. Bidirectional chemical synapses are characteristic of amacrine extensions rather than axons (Kölliker, 1896). Finally, the distance between presynaptic membrane and postsynaptic membrane can vary enormously, from about 20-30 nm at classical chemical synapses like the neuromuscular junction, to microns for the sympathetic innervation of blood vessels, to centimeters or meters for neurotransmitter released into the blood. Foster & Sherrington (1897, pp. 929, 969) supplied the term; Cajal (1894b, p. 447) had earlier called it an articulation. See Bullock & Horridge (1965, Tab. 2.1), Peters et al. (1991, Ch. 5), Cowan et al. (2001), Sandring (2008, p. 44-48). more details
Synapse en passant : French form of synapse-of-passage more details
Synapse in passing : Form of synapse-of-passage. more details
Synapse-of-passage ( Gerfen & Sawchenko, 1984 ) : A synapse (Foster & Sherrington, 1897) formed by either a terminal-of-passage or a bouton-of-passage; see Gerfen & Sawchenko (1984, pp. 231, 235, Fig. 10-F), Peters et al. (1991, pp. 150, 187, 358). more details
Synaptic bouton : Synonym for terminal (Cajal, 1899); see Jones & Cowan (1983, p. 306). more details
Synaptic cleft : The extracellular fluid domain between the plasma membrane of a particular presynaptic compartment (De Camilli et al., 2001) and the plasma membrane of a postsynaptic compartment (De Camilli et al., 2001); see De Camilli et al. (2001, p 115). more details
Synonym ( Swanson & Bota, 2010 ) : The semantic relationship between a standard term and a synonym is an identical definition, and for relevant Foundational Model of Connectivity terms implies identical connections. more details
Systems description of body ( Swanson & Bota, 2010 ) : One of two common orthogonal ways of describing completely the body; the other is the topographic description of body. An individual body system is a set of interconnected or interdependent parts that form a complex unity with a specific function; see Dorland's (2003), Oxford English Dictionary (1989). A set of body systems together describes completely the structure-function organization of the body; see Brash (1951, p. 4), Hollinshead (1974, pp. v-vii), Williams (1995, pp. 2, 15). Also called a systematic description of body. more details