The Croonian Lectures on Evolution and Dissolution of the Nervous System

~~~~~LEC.TUR L iAmAnAital reference in this lecture, I will state what I believe to b6E Ie i4rrtdhy of nervous centres, which accords with thie doctrffit I used to arrange them according to the 'on'phol,4gjpl 4vpi'ous of the nervous, ysten-spinal cord, emedula ,.II -nlow arr.ange t;hat c an aistomiqoJphy4iologial basisi tItt f 49h !OIeaially, as, to degree of indirectness witI which eehl ,repreo i b6t15-, or pt ef it.The lowest mnbtbr centresddn d tise an ffl *}+ii i¢<'qf1the sriial cord, ahd also the Jho`i6logouS ncuei fe 1 erves higlier up; they exteind 'fro the lowest spiuig a1~g)Iq .horns up tQ the niuclei for: the ocular wseles, They rre at 6a(wlolst -erobral and lowvest cerebellar centres; hence lesion, of tiI4*lt 'sit diflie parts they represernt from the whole central neervoti tWa.tf i iorhin the terebehlar systedA The low6st)i*6fie afE,W;4p stn sirapl9 and most -orgalnised centres; ea, hire7 Is1I) s lixhited r6*gion of the hddy indiroctly, it.-'yet.tmost n*Wy -iditectly; they are representative.' The duiddle motor etfit+es are' the coanvolutions Tnakingg iip FevrieWs ihotor re ion.'6 ai'eQ oi-e complet and less`orp_anis6d, an(l reprxescnt wfr ?qt,6XIt 1 e lbody ou11bly indirectly; they aFe re-reprQsehtative, Tiw.igsat nptor contres are coiivq1utions infroDntof -thoe oEcW6d moi*ob.itioii.' Isay " so-called," as I believe, and have 'urged fdr ^i ,that the whole anterior part of 'the brain is motor, o# ^,* 'iAVous I specbk more in detail,of this iii another lectture.¶1$,4igAst' motor q,eonres are the, iost cmpple,$ and least organised c s, aud r wesent wiidest regions, (inov,pnt, of ,ll , tts of the bty) tipIy indiretly ; they are re7re represeujtat vY.Tlst t otor qenitres rep)resent over againl whlat a4llth o'estt motor eun res have rereseated, -will be disputed iv fem.I go further, and say bat tthe highest motor centres (frontal lobes) represent over again, A .pqor,p ex.combihations, what the nmiddle xumtorncentres repre- set.All ecwpitjlation, there i-s inereasing.comphAxity, or greater ic yiQ .rQpresentation,so that ultimateLy the highest motor .,pqentior,, in other wvordg' no-orlinate, aovements of all NW rWX#oely iij thp most special and(I complex co-binations.;t -, ,tp.give th& scheme of sensory cenitres.'he nain concW- that thle.highest(chiefly) sensoly centres.-parts'Jbehin4 *,#eaqy region-and also the highest (cieAy) motor cete par4., an front of the.sp-called otor region-make up the physical lt,Xpf §o Nso Ciousnless and,(2) that' juk as cqnsciouaness rqhesemits oi#lJe whote, persou psychical, so its anatomical.Insis' (highest t;p' jeqKesents -the whole persoli physical--rep'esents impressions t of all parts of his body; in old-f laAguage, the highest centres are potentiallv the wlhole orga4nism.8tates of "iqesps ttenil survivals of the fittest states.ef centres.represent-,thq,woIe organism..j.,b4vxeeveral timles in4isted that the symptoniatology of alltueryoAs pw fl.,duplex; that in every casq there is a finegatve, ,Ud that t4f+s 1i,oa ositive element..I shall further.illus4rate thips by c s'so f insanit.I ought to have mentioned before that -r, f!Pir!y-years ago, pointed out that, ,a insanity, there.isbth a,l^vt;nf ja positiv e element.t~r.t)irtimer.Grauvilleo whb has ypr s (pplied the doctrine of disso61gioo, uses the ter and takes.note of the "e pogrc"--o6 the' lower layers {JVW ,*,Jt vthe lower, jevpls o, evoluion re niniig).^opjder pqst-epilepti states, whic4 are, pn;ficpy r9gde41 s8jpj~,o;j i a iaty5 f ,they are% 4wpyqr JjiQy or;hoqyer sftory-&ip^rtares from -notsl tmebtal :4tes..; I wish to show three things: (1) that after epileptic fits of different degrees of vei*ty, 'the l'a di eveat "d'ptIs' -of, diss t , and,.conse- qumt1jly 'different J"shillowsa" of iolution remnahin#; (2) to try to awc4cut 'i the stinee in some of; the cses-wof increased excitability of'thn vomt Arfangements of the &Mferent lower levMlsiqf eoltion renAiiing' i."thiN double attempt, I s3hall make -use of a prmiciple e"sentiaIlyT Aated 'log-ago by'Layook, but much'more explicitly by Aistie, (3)-that negative lesions of the highest centresaugse paraiysis.