Alphabetical list

Pachymeninges : Synonym for dura (Galen, c177); another form is pachymeninx; see Standring (2008, p. 389). more details

Pallium ( Burdach, 1822 ) : Synonym for cerebral cortex (Bauhin, 1605). Used first by Burdach for macrodissected adult humans (1822, p. 13), and by many others since, including His (1895, p. 85), Nauta & Feirtag (1986, p. 45). In Latin "pallium" refers to a mantle, cloak, or blanket (Oxford Latin Dictionary, 1996). more details

Parasympathetic ganglia ( PSY ; Kuntz, 1934 ) : Synonym for terminal ganglia (Gaskell, 1886); apparently named thus by Kuntz (1934, p. 126). more details

Paravertebral ganglia ( GPAS ; Langley, 1900 ) : A topographic division of autonomic ganglia (Langley, 1900) associated with the sympathetic trunk (Winslow, 1733) and branches arising directly from it, including the carotid ganglion (Lobstein, 1831), sympathetic trunk ganglia (Winslow, 1733), and intermediate ganglia. Falloppio (1561; see Johnstone, 1765, p. 177) is credited with discovering them in macrodissected adult humans, for contemporary terminology see Durward (1951, p. 1126). more details

Paravertebral nerves ( PAN ; Langley, 1898 ) : A topographic division of autonomic nerves (Langley, 1898) that macroscopically appear to arise from paravertebral ganglia and/or the sympathetic trunk (Winslow, 1733). more details

Parencephalon ( Aristotle ) : Synonym for cerebellum (Aristotle). This is the original term, derived from the Greek, used by Aristotle in Historia Animalium for the cerebellum; see Longrigg (1993, p. 212) and Clarke & O'Malley (1996, pp. 629-630). more details

Parencephalon ( Kupffer, 1893 ) : Synonym for thalamus (His, 1893a); in the original German, Nebenhirn, p. 61 and Fig. F-p. more details

Parent axon : Synonym for axon trunk. Galen in the second century used the term parent for macrodissected nerves (Herophilus, c335-280 BC) as a whole; see translation by Duckworth (1962, p. 203). more details

Pars optica hypothalami ( His, 1893b ) : Basically it consists of the anterior and tuberal regions (Swanson, 1987, p. 2) of the hypothalamus (Kuhlenbeck, 1927). It is part of the telencephalon (His, 1893b); see His (1893b, p. 178; 1895, p. 158). more details

Partial correspondence ( Swanson & Bota, 2010 ) : In neuroanatomy many terms do not fit exactly into any part of the structural hierarchy. Such terms partly correspond to a standard term somewhere in the hierarchy, and should be defined (described) with reference to the immediately higher standard term within which it completely fits. The concept of a partly corresponding term is important because such a term generally does not share all of the properties of any particular reference term and thus cannot fit exactly anywhere within the hierarchy as such-it does not have a strict PART-OF relationship with any component of the Foundational Model of Connectivity hierarchy. This is because gray matter regions and neuron types (Bota & Swanson, 2007) generally are not homogeneous; instead, they have defining and differentiable features in parameter space that occur in gradients. As a result different sites within a gray matter region generally have different features and thus different microconnections. more details

Partly corresponds : Verb form of partial correspondence; partly corresponding is another form. more details

Passing synapse : English form of "synapse en passant". more details

Pathway : The component of a connection that is demonstrated in a specific tracing experiment or analysis. This definition is specific to the Foundational Model of Connectivity where it is useful for description to have terms distinguishing between pathway and connection. As with connections, there can be macropathways, mesopathways, and micropathways. Other usages of the word pathway are common, especially as a synonym for connection or projection. The term path or pathway was used for a route of transmission in the nervous system (Monro, 1783) as long ago as Galen (c173); see translations by May (1968, pp. 401-402) and Clarke & O'Malley, (1996, p. 630). more details

Perikaryon ( Foster & Sherrington, 1897 ) : The cell body (Deiters, 1865) without the cell nucleus (Brown, 1833); p. 928, also see Peters et al. (1991, p. 14). more details

Peripheral ( Barclay, 1803 ) : Toward the surface of the body. Barclay (1803, pp. 120-121, 164) introduced a formal distinction between central (Barclay, 1803) and peripheral. more details

Peripheral ganglia ( GPR ; Swanson & Bota, 2010 ) : A peripheral ganglion is a macroscopic aggregation of neurons (Waldeyer, (1891), that is, a gray matter region, in the peripheral nervous system (Meckel, 1817) of invertebrates and vertebrates; see Bullock & Horridge (1965, p. 51), also see ganglion (Galen, c173). more details

Peripheral longitudinal communicating branch : The segment of a peripheral nerve cord trunk between two peripheral ganglia associated with the corresponding peripheral nerve cord as a whole. more details

Peripheral nerve cord ( Swanson & Bota, 2010 ) : A topographic division that has a longitudinal peripheral nerve cord trunk (equivalent to a white matter tract) with a series of more or less regularly spaced peripheral ganglia along its course, and a trunk segment between two adjacent ganglia called a peripheral longitudinal communicating branch. The prototypical vertebrate example is the sympathetic trunk (Winslow, 1733) with its sympathetic trunk ganglia (Winslow, 1733)-together the sympathetic cord. more details

Peripheral nerve cord trunk : The equivalent of a white matter tract for a peripheral nerve cord, with peripheral ganglia distributed along its length. more details

Peripheral nervous system ( PNS ; Meckel, 1817 ) : In bilateral animals, a topographic division with condensations of the nervous system (Monro, 1783) consisting of nerves (Herophilus, c335-280 BC) and ganglia (Galen, c173). When a PNS is present, its obligate companion topographic division is a central nervous system (Meckel, 1817). There is no known isolated part of the PNS that does not have a connection to the rest of the nervous system; see Bullock & Horridge (1965, pp. 9-14). While the nerves were discovered by Herophilus (335-280 BC; see Solmsen, 1961, p. 185; von Staden, 1989, pp. 250-252), the term peripheral nervous system as currently understood was first used by Meckel (1817; see English translation 1832, p. 153). more details

Pia ( PI ; Galen, c192 ) : The innermost of the meninges (Edwin Smith Surgical Papyrus, c1700 BC), closely covering the brain (Edwin Smith Surgical Papyrus, c1700 BC) and spinal cord (Galen, c162-c166) and consisting of reticular, elastic, and collagenous fibers. It is histologically similar to the arachnoid (Blasius, 1666), and the two are often considered together as the leptomeninges; see Dorland's (2003), Standring (2008, p. 389). The pia was apparently known to Hippocrates in Places in Man (see translation by Potter, 1955, p. 23) and was described and named such by Galen (c192; see translation by Duckworth, 1962, p. 6). more details

Pia mater ( Ali ibn' ul-Abbas, d994 ) : Synonym for pia (Galen, c192); for naming see Wiberg (1914, p. 86-89). more details

Plexus ( plx ; Galen, c192 ) : A general term for a group of interconnecting neurons (Waldeyer, 1891) or nerve (Herophilus, c335-280 BC) components that may be a sheet of interwoven fibers or a course mesh of communicating nerves, without or with neuron cell bodies (Deiters, 1865), including ganglia (Galen, c173); see Oxford English Dictionary, 1989; Bullock & Horridge, 1965, p. 1606). Examples include nerve nets, prevertebral plexuses, and spinal nerve plexuses (with postplexus spinal nerves distal to them). Galen (c192; see translation by Duckworth, 1962, p. 243) used the term plexus in describing the macrodissected adult mammalian brachial plexus (Camper, 1760). more details

Pons ( P ; Haller, 1747 ) : The ventral (Schulze, 1893) topographic division of the hindbrain (Baer, 1837); the dorsal (Barclay, 1803) topographic division is the cerebellum (Aristotle). The middle cerebellar peduncle on the periphery of the macrodissected adult human pons ("bridge" in English) was identified by Varolio (1573, Fig. I, f. 17v; also see Clarke & O'Malley 1996, pp. 634-635, 821). Collins (1685, see Tab. 48-L, his caudex of medulla oblongata) identified the pons as defined here, and Haller (1747, see translation by Mihles, 1754, pp. 287, 296) provided the term itself. Pons Varolii (Bell, 1802) is a synonym. more details

Pons Varolii ( Bell, 1802 ) : Synonym for macrodissected adult human pons (Haller, 1747); see Pls. VII-8, IX-N, X-b. more details

Posterior ( Aristotle ) : Caudal (Cleland, 1879) in relation to the longitudinal axis (Barclay, 1803); commonly used in this way for comparative anatomy, as was the case for Aristotle in De Partibis Animalium; see, for example, translation of Ogle (1912, 684b-25). Vicq d'Azyr (1786, pp. 51, 58) first clearly defined the term as behind or opposite the face, corresponding in most vertebrates to caudal, and in humans to dorsal (Barclay, 1803) or posterior (Galen, c177). Discarding the ambiguous terms anterior and posterior has been urged since at least 1880 (Spitzka, 1880, p. 75); also see anterior (Aristotle), Standring (2008, Fig. 1). more details

Posterior ( Galen, c177 ) : Dorsal (Barclay, 1803) in relation to the longitudinal axis (Barclay, 1803); commonly used in this way for human and other primate anatomy, as was the case for Galen; see translations of Singer (1999, p. 129) and Duckworth (1962, pp. 229, 231). Also see anterior (Aristotle), Standring (2008, Fig. 1). more details

Postplexus spinal nerves : Spinal nerves (Camper, 1760) distal to the spinal nerve plexuses. The major ones were described for macrodissected animals except human in the second century by Galen; see translations of Duckworth (1962, pp. 230-264) and May (1968, pp. 598-603). more details

Postsynaptic : Referring to the postsynaptic compartment (De Camilli et al., 2001). more details

Postsynaptic compartment ( De Camilli et al., 2001 ) : The part of a chemical synapse that binds neurotransmitters released from the presynaptic compartment (De Camilli et al., 2001) into the synaptic cleft; see pp. 112-113. more details

Presynaptic : Referring to the presynaptic compartment (De Camilli et al., 2001). more details

Presynaptic compartment ( De Camilli et al., 2001 ) : The part of a chemical synapse that releases neurotransmitter into the synaptic cleft for action on the postsynaptic compartment (De Camilli et al., 2001); see p. 93 ff. more details

Prevertebral ganglia ( GPRS ; Gaskell, 1886 ) : A topographic division of autonomic ganglia (Langley, 1900) associated with the prevertebral plexuses. Galen in the second century saw at least part of them-the celiac ganglion (Walter, 1783)-in macrodissected adult animals except humans; see translations by Duckworth (1962, pp. 217-218), May (1968, pp. 695-696, 711), Smith (1971, p. 179). Gaskell (1886, p. 3) named them for vertebrates based on structure-function criteria. more details

Prevertebral nerves ( PNE ; Gaskell, 1886 ) : A topographic division of autonomic nerves (Langley, 1898) that macroscopically appear to arise from prevertebral ganglia (Gaskell, 1886) and/or prevertebral plexuses, and typically end in terminal plexuses and/or terminal ganglia (Gaskell, 1886). more details

Prevertebral plexuses ( PVE ; Winslow, 1733 ) : A topographic division of autonomic nerves (Langley, 1898) that form an interconnected series of more or less distinguishable perivascular thoracic, abdominal, and pelvic plexuses (Galen, c192) of small communicating branches (Winslow, 1733) or anastomotic nerve fiber bundles. Their functional composition is complex with varying mixtures of postganglinic sympathetic axons (Kölliker, 1896) from paravertebral nerves, preganglionic parasympathetic axons, visceral afferent fibers, and prevertebral ganglia (Gaskell, 1886) that are mostly sympathetic-except in the inferior hypogastric plexus where there is a mixture of sympathetic and parasympathetic neurons (Waldeyer, 1891); see Durward (1951, pp. 1120, 1128, 1138) for name and Williams & Warwick (1980, pp. 1132-1137). more details

Process : Can be a short form of neuron process (Purkinje, 1838), a neuron extension. more details

Projection : Synonym for connection. more details

Projections : Synonym for connections. more details

Prosencephalon ( Mihalkovics, 1877 ) : Original Latin form of macrodissected adult vertebrate forebrain (Goette, 1873). more details

Prosencephalon ( Sharpey et al., 1867 ) : Original Latin form of forebrain (Baer, 1837), the endbrain (Kuhlenbeck, 1927); p. 577. more details

Proximal ( Barclay, 1803 ) : Toward the origin of an object like a tentacle, limb, or nerve; the opposite of distal (Barclay, 1803). Introduced by Barclay (1803, pp. 124-125, 164), also see Standring (2008, p. xxii). more details