the origin and nature of emotions-第5节

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pallor；　the　breathing　is　labored；　the　wings　of　the　nostrils　are　widely　dilated；　‘there　is　a　gasping　and　convulsive　motion　of　the　lips；　a　tremor　on　the　hollow　cheek；　a　gulping　and　catching　of　the　throat'；　the　uncovered　and　protruding　eyeballs　are　fixed　on　the　object　of　terror；　or　they　may　roll　restlessly　from　side　to　side。　　*　*　*　The　pupils　are　said　to　be　enormously　dilated。　　All　the　muscles　of　the　body　may　become　rigid；　or　may　be　thrown　into　convulsive　movements。　The　hands　are　alternately　clenched　and　opened；　often　with　a　twitching　movement。　　The　arms　may　be　protruded；　as　if　to　avert　some　dreadful　danger；　or　may　be　thrown　wildly　over　the　head。　*　*　*　In　other　cases　there　is　a　sudden　and　uncontrollable　tendency　to　headlong　flight；　and　so　strong　is　this　that　the　boldest　soldiers　may　be　seized　with　a　sudden　panic。　　As　fear　rises　to　an　extreme　pitch；　the　dreadful　scream　of　terror　is　heard。　　Great　beads　of　sweat　stand　on　the　skin。　　All　the　muscles　of　the　body　are　relaxed。　Utter　prostration　soon　follows；　and　the　mental　powers　fail。　The　intestines　are　affected。　　The　sphincter　muscles　cease　to　act　and　no　longer　retain　the　contents　of　the　body。　*　*　*　Men；　during　numberless　generations；　have　endeavored　to　escape　from　their　enemies　or　danger　by　headlong　flight；　or　by　violently　struggling　with　them；　and　such　great　exertions　will　have　caused　the　heart　to　beat　rapidly；　the　breathing　to　be　hurried；　the　chest　to　heave；　and　the　nostrils　to　be　dilated。　As　these　exertions　have　often　been　prolonged　to　the　last　extremity；　the　final　result　will　have　been　utter　prostration；　pallor；　perspiration；　trembling　of　all　the　muscles；　or　their　complete　relaxation。　And　now；　whenever　the　emotion　of　fear　is　strongly　felt；　though　it　may　not　lead　to　any　exertion；　the　same　results　tend　to　reappear；　through　the　force　of　inheritance　and　association〃＇*＇　（Fig。　12）。


＇*＇　Darwin：　　Expression　of　the　Emotions　in　Man　and　Animals。


In　an　experimental　research；　we　found　evidence　that　the　physiologic　phenomena　of　fear　have　a　physical　basis。　　This　evidence　is　found　in　the　morphologic　alterations　in　the　brain…cells；　which　are　similar　to　those　observed　in　certain　stages　of　surgical　shock　and　in　fatigue　from　muscular　exertion　（Figs。　2；　4；　5；　and　13）。　For　the　present；　we　shall　assume　that　fear　is　a　REPRESENTATION　of　trauma。　Because　fear　was　created　by　trauma；　fear　causes　a　discharge　of　the　energy　of　the　nervous　system　by　the　law　of　phylogenetic　association。　The　almost　universal　fear　of　snakes；　of　blood；　and　of　death　and　dead　bodies　may　have　such　a　phylogenetic　origin。　It　was　previously　stated　that　under　the　stimulus　of　fear　animals　show　preternatural　strength。　　An　analysis　of　the　phenomena　of　fear　shows　that；　as　far　as　can　be　determined；　all　the　functions　of　the　body　requiring　the　expenditure　of　energy；　and　which　are　of　no　direct　assistance　in　the　effort　toward　self…preservation；　are　suspended。　In　the　voluntary　expenditure　of　muscular　energy；　as　in　the　chase；　the　suspension　of　other　functions　is　by　no　means　so　complete。　Fear　and　trauma　may　drain　to　the　last　dreg　the　dischargeable　nervous　energy；　and；　therefore；　the　greatest　possible　exhaustion　may　be　produced　by　fear　and　trauma。


Summation

In　the　discharge　of　energy；　summation　plays　an　important　role。　Summation　is　attained　by　the　repetition　of　stimuli　at　such　a　rate　that　each　succeeding　stimulus　is　applied　before　the　nerve…cells　have　returned　to　the　resting　stage　from　the　preceding　stimulus。　If　drops　of　water　fall　upon　the　skin　from　a　sufficient　height　to　cause　the　slightest　unpleasant　sensation；　and　at　such　a　rate　that　before　the　effect　of　the　stimulus　of　one　drop　has　passed　another　drop　falls　in　precisely　the　same　spot；　there　will　be　felt　a　gradually　increasing　painful　sensation　which　finally　becomes　unbearable。　This　is　summation　of　stimuli。　　When；　for　a　long　time；　a　patient　requires　frequent　painful　wound　dressings；　there　is　a　gradual　increase　in　the　acuteness　of　the　pain　of　the　receptors。　This　is　caused　by　summation。　　In　a　larger　sense；　the　entire　behavior　of　the　individual　gives　considerable　evidence　of　summation；　_e。　g_。；　in　the　training　of　athletes；　the　rhythmic　discharge　of　muscular　energy　at　such　intervals　that　the　resting　stage　is　not　reached　before　a　new　exercise　is　given　results　in　a　gradual　ascent　in　efficiency　until　the　maximum　is　reached。　　This　is　summation；　and　summation　plays　a　large　role　in　the　development　of　both　normal　and　pathologic　phenomena。

We　have　now　pointed　out　the　manner　in　which　at　least　a　part　of　the　nervous　energy　of　man　may　be　discharged。　The　integrative　action　of　the　nervous　system　and　the　discharge　of　nervous　energy　by　phylogenetic　association　may　be　illustrated　by　their　analogy　to　the　action　of　an　electric　automobile。　The　electric　automobile　is　composed　of　four　principal　parts：　The　motor　and　the　wheels　（the　muscular　system　and　the　skeleton）；　the　cells　of　the　battery　containing　stored　electricity　（brain…cells；　nervous　energy）；　the　controller；　which　is　connected　with　the　cells　by　wiring　（the　receptors　and　the　nerve…fibers）；　and　an　accelerator　for　increasing　the　electric　discharge　（thyroid　gland？）。　The　machine　is　so　constructed　that　it　acts　as　a　whole　for　the　accomplishment　of　a　single　purpose。　When　the　controller　is　adjusted　for　going　ahead　（adequate　stimulus　of　a　receptor）；　then　the　conducting　paths　（the　final　common　path）　for　the　accomplishment　of　that　purpose　are　all　open　to　the　flow　of　the　current　from　the　battery；　and　the　vehicle　is　integrated　to　go　ahead。　It　spends　its　energy　to　that　end　and　is　closed　to　all　other　impulses。　When　the　controller　is　set　for　reverse；　by　this　adequate　stimulus　the　machine　is　integrated　to　back；　and　the　battery　is　closed　to　all　other　impulses。　　Whether　integrated　for　going　forward　or　backward；　if　the　battery　be　discharged　at　a　proper　rate　until　exhausted；　the　cells；　though　possessing　no　more　power　（fatigue）；　have　sustained　no　further　impairment　of　their　elements　than　that　of　normal　wear　and　tear。　　Furthermore；　they　may　be　restored　to　normal　activity　by　recharging　（rest）。　If　the　vehicle　be　placed　against　a　stone　wall；　and　the　controller　be　placed　at　high…speed　（trauma　and　fear）；　and　if　the　accelerator　be　used　as　well　（thyroid　secretion？）；　though　the　machine　will　not　move；　not　only　will　the　battery　soon　be　exhausted；　but　the　battery　elements　themselves　will　be　seriously　damaged　（exhaustionsurgical　shock）。

We　have　now　presented　some　evidence　that　nervous　energy　is　discharged　by　the　adequate　stimulation　of　one　or　more　of　the　various　receptors　that　have　been　developed　in　the　course　of　evolution。　In　response　to　an　adequate　stimulus；　the　nervous　system　is　integrated　for　a　specific　purpose　by　the　stimulated　receptor；　and　but　one　stimulus　at　a　time　has　possession　of　the　final　common　path　the　nerve　mechanisms　for　action。　　The　most　numerous　receptors　are　those　for　harmful　contact；　these　are　the　nociceptors。　The　effect　of　the　adequate　stimulus　of　a　nociceptor　is　like　that　of　pressing　an　electric　button　that　sets　great　machinery　in　motion。

With　this　conception；　the　human　body　may　be　likened　to　a　musical　instrumentan　organthe　keyboard　of　which　is　composed　of　the　various　receptors；　upon　which　environment　plays　the　many　tunes　of　life；　and　written　within　ourselves　in　symbolic　language　is　the　history　of　our　evolution。　　The　skin　may　be　the　〃Rosetta　Stone〃　which　furnishes　the　key。


Anoci…association


By　the　law　of　phylogenetic　association；　we　are　now　prepared　to　make　a　practical　application　of　the　principles　of　the　discharge　of　nervous　energy。　　In　the　case　of　a　surgical　operation；　if　fear　be　excluded　and　if　the　nerve…paths　between　the　field　of　operation　and　the　brain　be　blocked　with　cocain；＇*＇　no　discharge　of　energy　will　be　caused　by　the　operation；　hence　no　shock；　no　exhaustion；　can　result。　Under　such　conditions　the　nervous　system　is　protected　against　noci…association；　resulting　from　noci…perception　or　from　an　adequate　stimulation　of　nociceptors。　　The　state　of　the　patient　in　whom　all　noci…associations　are　excluded　can　be　described　only　by　coining　a　new　word。　　That　word　is　〃anoci…association〃　（Fig。　14）。


＇*＇　See　footnote；　page　4。@@@


The　difference　between　anesthesia　and　anoci…association　is　that；　although　_inhalation　anesthesia_　confers　the　beneficent　loss　of　consciousness　and　freedom　from　pain；　it　does　not　prevent　the　nerve　impulses　from　reaching　and　influencing　the　brain；　and　therefore　does　not　prevent　surgical　shock　nor　the　train　of　later　nervous　impairments　so　well　described　by　Mumford。　　_Anoci…association_　excludes　fear；　pain；　shock；　and　postoperative　neuroses。　　_Anoci…association_　is　accomplished　by　combining　the　special　management　of　patients　（applied　psychology）；　morphin；　inhalation　anesthesia；　and　local　anesthesia。

We　have　now　presented　in　summary　much　of　the　mass　of　experimental　and　clinical　evidence　we　have　accumulated　in　support　of　our　principal　theme；　which　is　that　the　discharge　of　nervous　energy　is　accomplished　in　accordance　with　the　law　of　phylogenetic　association。　If　this　point　seems　to　have　been　emphasized　unduly；　it　is　because　we　expect　to　rear　upon　this　foundation　a　clinical　structure。　How　does　this　hypothesis　apply　to　surgical　operations？


Prevention　of　Shock　by　the　Application　of　the　Principle　of　Anoci…association



Upon　this