the origin and nature of emotions-第28节

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n　of　the　Nissl　substance　is　also　lessened　or　prevented　by　nitrous　oxid。　But　morphin　does　not　prevent　the　action　of　adrenalin　injected　into　the　circulation；　hence　the　control　of　morphin　over　energy　expenditure　is　exerted　directly　on　the　brain…cells。　Apparently　morphin　and　nitrous　oxid　both　act　through　this　interference　with　oxidation　in　the　brain。　　We；　therefore；　conclude　that　within　a　certain　range　of　acidity　of　the　blood　adrenalin　can　unite　with　the　brain…cells　only　through　the　mediation　of　oxygen；　and　that　the　combination　of　adrenalin；　oxygen；　and　certain　brain…cell　constituents　causes　the　electric　discharge　that　produces　heat　and　motion。　In　this　interrelation　of　the　brain　and　the　adrenals　we　have　what　is；　perhaps；　the　master　key　to　the　automatic　action　of　the　body。　Through　the　special　senses　environmental　stimuli　reach　the　brain　and　cause　it　to　liberate　energy；　which　in　turn　activates　certain　other　organs　and　tissues；　among　which　are　the　adrenals。　　The　increased　output　of　adrenalin　activates　the　brain　to　still　greater　activity；　as　a　result　of　which　again　the　entire　sympathetic　nervous　system　is　further　activated；　as　is　manifested　by　increased　heart　action；　more　rapid　respiration；　raised　blood…pressure；　increased　output　of　glycogen；　increased　power　of　the　muscles　to　metabolize　glucose；　etc。

If　this　conclusion　be　well　founded；　we　should　find　corroborative　evidence　in　histologic　changes　in　that　great　storehouse　of　potential　energy；　the　liver；　as　a　result　of　the　application　of　each　of　the　adequate　stimuli　which　produced　brain…cell　and　adrenal　changes。


The　Liver

Prolonged　insomnia；　prolonged　physical　exertion；　infections；　injections　of　toxins　and　of　strychnin；　rage　and　fear；　physical　injury　under　anesthesia；　in　fact；　all　the　adequate　stimuli　which　affected　the　brain　and　the　adrenals；　produced　constant　and　identical　histologic　changes　in　the　liverthe　cells　stained　poorly；　the　cytoplasm　was　vacuolated；　the　nuclei　were　crenated；　the　cell　membranes　were　irregular；　the　most　marked　changes　occurring　in　the　cells　of　the　periphery　of　the　lobules　（Figs。　69　and　70）。　In　prolonged　insomnia　the　striking　changes　in　the　liver　were　repaired　by　one　seance　of　sleep。

Are　the　histologic　changes　in　the　liver　cells　due　to　metabolism　or　toxic　products；　or　are　they　〃work〃　changes　incident　to　the　conversion　of　latent　into　kinetic　energy？　　Are　the　brain；　adrenals；　and　liver　interdependent？　The　following　facts　establish　the　answers　to　these　queries：

（1）　The　duration　of　life　after　excision　of　the　liver　is　about　the　same　as　after　adrenalectomyapproximately　eighteen　hours。

（2）　The　amount　of　glycogen　in　the　liver　was　diminished　in　all　the　experiments　showing　brain…adrenal　activity；　and　when　the　histologic　changes　were　repaired；　the　normal　amount　of　glycogen　was　again　found。

（3）　In　crossed　circulation　experiments　changes　were　found　in　the　liver　of　the　animal　whose　brain　received　the　stimulus。

From　these　premises　we　must　consider　that　the　brain；　the　adrenals；　and　the　liver　are　mutually　dependent　on　one　another　for　the　conversion　of　latent　into　kinetic　energy。　　Each　is　a　vital　organ；　each　equally　vital。　It　may　be　said　that　excision　of　the　brain　may　apparently　cause　death　in　less　time　than　excision　of　the　liver　or　adrenals；　but　this　statement　must　be　modified　by　our　definition　of　death。　　If　all　the　brain　of　an　animal　be　removed　by　decapitation；　its　body　may　live　on　for　at　least　eleven　hours　if　its　circulation　be　maintained　by　transfusion。　An　animal　may　live　for　weeks　or　months　after　excision　of　the　cerebral　hemispheres　and　the　cerebellum；　while　an　overtransfused　animal　may　live　many　hours；　days　even；　after　the　destruction　of　the　medulla。　It　is　possible　even　that　the　brain　actually　is　a　less　vital　organ　than　either　the　adrenals　or　the　liver。

In　our　research　to　discover　whether　any　other　organs　should　be　included　with　the　brain；　the　adrenals；　and　the　liver　in　this　mutually　interdependent　relation；　we　hit　upon　an　experiment　which　throws　light　upon　this　problem。

Groups　of　rabbits　were　gently　kept　awake　for　one　hundred　hours　by　relays　of　students；　an　experiment　which　steadily　withdrew　energy　but　caused　not　the　slightest　physical　or　emotional　injury　to　any　of　them；　no　drug；　toxin；　or　other　agent　was　given　to　them；　they　were　given　sufficient　food　and　drink。　　In　brief；　the　internal　and　external　environments　of　these　animals　were　kept　otherwise　normal　excepting　for　the　gentle　stimuli　which　insured　continued　wakefulness。　This　protracted　insomnia　gradually　exhausted　the　animals　completely；　some　to　the　point　of　death　even。　　Some　of　the　survivors　were　killed　immediately　after　the　expiration　of　one　hundred　hours　of　wakefulness；　others　after　varying　intervals。

Histologic　studies　were　made　of　every　tissue　and　organ　in　the　body。　Three　organs；　the　brain；　the　adrenals；　and　the　liver；　and　these　three　only；　showed　histologic　changes。　　In　these　three　organs　the　histologic　changes　were　marked；　and　were　almost　wholly　repaired　by　one　seance　of　sleep。　In　each　instance　these　histologic　changes　were　identical　with　those　seen　after　physical　exertion；　emotions；　toxins；　etc。＇*＇　It　would　appear；　then；　that　these　three　organs　take　the　stress　of　life　the　brain　is　the　〃battery；〃　the　adrenals　the　〃oxydizer；〃　and　the　liver　the　〃gasoline　tank。〃　　This　clear…cut　insomnia　experiment　corresponds　precisely　with　our　other　brain…adrenal　observations。


＇*＇　Further　studies　have　given　evidence　that　the　elimination　of　the　acids　resulting　from　energy…transformation　as　well　as　the　conversion　of　energy　stored　in　the　kinetic　organs　causes　histologic　changes　in　the　liver；　the　adrenals；　and　possibly　in　the　brain。


With　these　three　kinetic　organs　we　may　surely　associate　also　the　〃furnace；〃　the　muscles；　in　which　the　energy　provided　by　the　brain；　adrenals；　and　liver；　plus　oxygen；　is　fabricated　into　heat　and　motion。

Benedict；　in　his　monumental　work　on　metabolism；　has　demonstrated　that　in　the　normal　state；　at　least；　variations　in　the　heart…beat　parallel　variations　in　metabolism。　　He　and　others　have　shown　also　that　all　the　energy　of　the　body；　whether　evidenced　by　heat　or　by　motion；　is　produced　in　the　muscles。　　In　the　muscles；　then；　we　find　the　fourth　vital　link　in　the　kinetic　chain。　　The　muscles　move　the　body；　circulate　the　blood；　effect　respiration；　and　govern　the　body　temperature。　They　are　the　passive　servants　of　the　brain…adrenal…liver　syndrome。

Neither　the　brain；　the　adrenals；　the　liver；　nor　the　muscles；　however；　nor　all　of　these　together；　have　the　power　to　change　the　rate　of　the　expenditure　of　energy；　to　make　possible　the　increased　expenditure　in　adolescence；　in　pregnancy；　in　courting；　and　mating；　in　infections。　No　one　of　these　organs；　nor　all　of　them　together；　can　act　as　a　pace…maker　or　sensitizer。　　The　brain　acts　immediately　in　response　to　the　stimuli　of　the　moment；　the　adrenals　respond　instantly　to　the　fickle　brain　and　the　effects　of　their　actions　are　fleeting；　the　liver　contains　fuel　only　and　cannot　activate；　and　the　muscles　in　turn　act　as　the　great　furnace　in　which　the　final　transformation　into　available　energy　is　made。　　The　Thyroid

Another　organthe　thyroidhas　the　special　power　of　governing　the　RATE　OF　DISCHARGE　of　energy；　in　other　words；　the　thyroid　is　the　pace…maker。　Unfortunately；　the　thyroid　cannot　be　studied　to　advantage　either　functionally　or　histologically；　for　there　is　as　yet　no　available　test　for　thyroid　secretion　in　the　blood　as　there　is　for　adrenalin；　and　thyroid　activity　is　not　attended　by　striking　histologic　changes。　Therefore　the　only　laboratory　studies　which　have　been　satisfactory　thus　far　are　those　by　which　the　iodin　content　of　the　thyroid　has　been　established。　　Iodin　is　stored　in　the　colloid　lacunae　of　the　thyroid　and；　in　combination　with　certain　proteins；　is　the　active　agent　of　the　thyroid。

Beebe　has　shown　that　electric　stimulation　of　the　nerve　supply　of　the　thyroid　diminishes　the　amount　of　iodin　which　it　contains；　and　it　is　known　that　in　the　hyperactive　thyroid　in　Graves'　disease　the　iodin　content　is　diminished。　　The　meagerness　of　laboratory　studies；　however；　is　amply　compensated　by　the　observations　which　the　surgeon　has　been　able　to　make　on　a　vast　scaleobservations　which　are　as　definite　as　are　the　results　of　laboratory　experiments。

The　brain…cells　and　the　adrenals　are　securely；　concealed　from　the　eye　of　the　clinician；　hence　the　changes　produced　in　them　by　different　causes　escape　his　notice；　but　the　thyroid　has　always　been　closely　scrutinized　by　him。　　The　clinician　knows　that　every　one　of　the　above…mentioned　causes　of　increased　brain…cell；　adrenal；　liver　and　muscle　activity　may　cause　an　increase　in　the　activity　of　both　the　normal　or　the　enlarged　thyroid；　and　lie　knows　only　too　well　that　in　a　given　case　of　exophthalmic　goiter　the　same　stimuli　which　excite　the　brain；　the　adrenals；　the　liver；　and　the　muscles　to　increased　activity　will　also　aggravate　this　disease。

The　function　of　the　thyroid　in　the　kinetic　chain　is　best　evidenced；　however；　by　its　role　in　the　production　of　fever。　　Fever　results　from　the　administration　of　thyroid　extract　alone　in　large　doses。　In　the　hyperactivity　of　the　thyroid　in　exophthalmic　goiter　one　sees　a　marked　tendency　to　fever；　in　severe　cases　there　is　daily　fever。　In　fact；　in　Graves'　disease　we　find　displayed　to　an　extraordin