the origin and nature of emotions-第31节

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ther；　and　by　nitrous　oxid。　　In　addition　our　tests　have　shown　that　under　ether　the　increase　of　the　H…ion　concentrationacidityis　more　gradual　than　under　nitrous　oxid；　an　observation　which　accords　well　with　the　fact　that　nitrous　oxid　more　quickly　induces　anesthesia　than　does　ether。

Further　striking　testimony　in　favor　of　the　hypothesis　that　the　production　of　acidity　by　inhalation　anesthetics　is　the　method　by　which　anesthesia　itself　is　produced　is　found　in　the　fact　that　although　lethal　doses　of　acid　cause　muscular　paralysis；　yet　this　paralysis　may　be　mitigated　by　adrenalinwhich　is　alkaline。　This　observation　may　explain　in　part　the　remarkable　success　of　the　method　of　resuscitation　devised　by　me；　in　which　animals　〃killed〃　by　anesthetics　and　asphyxia　are　revived　by　the　use　of　adrenalin。

In　animals　under　inhalation　anesthesia　Williams　found　that　no　nerve…current　could　be　detected　by　the　Einthoven　string　galvanometer；　a　fact　which　might　be　explained　by　postulating　that　nerve…currents　can　flow　from　the　brain　to　the　muscles　and　glands　only　when　there　is　a　difference　of　potential。　　Any　variation　from　the　normal　alkalinity　of　the　body　must　change　the　difference　in　potential。　Since　the　nerve…currents　in　animals　under　anesthesia　are　not　demonstrable　by　any　apparatus　at　our　command；　and　since　anesthesia　produces　acidity；　then　we　may　infer　that　acidity　reduces　the　difference　in　potential。　As　long　as　there　is　life；　a　galvanometer　of　sufficient　delicacy　would　perforce　detect；　a　nerve…current　until　the　acidity　increased　to　such　a　point　as　to　reduce　the　difference　in　potential　to　zero　the　point　of　death。　　If　at　this　point　a　suitable　alkali　adrenalin　solutioncan　be　introduced　quickly　enough；　the　vital　difference　in　potential　may　be　restored　and　the　life　processes　will　be　renewed。　Bearing　especially　on　this　point　is　the　fact　that　if　adrenalin　in　sufficient　quantities　be　administered　simultaneously　with　an　acid；　it　will　not　only　prevent　the　fall　in　blood…pressure　usually　caused　by　the　acid；　but　will　also　prevent　the　histologic　changes　in　the　brain；　adrenals；　and　liver　which　are　usually　caused　by　the　intravenous　injection　of　acids。

This　hypothesis　regarding　the　cause　of　anesthesia　and　unconsciousness　explains　and　harmonizes　many　facts。　　It　explains　how　asphyxia；　overwhelming　emotion；　and　excessive　muscular　exertion；　by　causing　acidity；　may　produce　unconsciousness。　　It　explains　the　acidosis　which　results　from　starvation；　from　uremia；　from　diabetes；　from　Bright's　disease；　and　supplies　a　reason　for　the　use　of　intravenous　infusions　of　sodium　bicarbonate　to　overcome　the　coma　of　diabetes　and　uremia　（Fig。　76）。　It　may　explain　the　quick　death　from　chloroform　and　nitrous　oxid；　and　may　perhaps　show　why　unconsciousness　is　so　commonly　the　immediate　precursor　of　death。

One　of　the　most　noticeable　immediate　effects　of　the　administration　of　an　inhalation　anesthetic　is　a　marked　increase　in　the　rapidity　and　force　of　the　respiration。　　The　respiratory　center　has　evidently　been　evolved　to　act　with　an　increase　of　vigor　which　is　proportional　within　certain　limitsto　the　increase　in　the　H…ion　concentration；　whereas　the　centers　governing　the　voluntary　muscles　are　inhibited。　In　this　antithetic　reaction　of　the　higher　cortical　centers　and　the　lower　centers　in　the　medulla　to　acidity　we　find　a　remarkable　adaptation　which　prevents　the　animal　from　killing　itself　by　the　further　increase　in　acidity　which　would　be　produced　by　muscular　activity。　　That　is；　as　the　acidity　produced　by　muscular　action　increases　and　threatens　life；　the　respiratory　action；　by　which　carbon　dioxid　is　eliminated　and　oxygen　supplied；　is　increased；　while　the　driving　power　of　the　brain；　which　produces　acidity；　is　diminished　or　even　inhibited　entirely；　that　is；　the　state　of　unconsciousness　or　anesthesia　is　reached。　We　conclude　first　that；　without　this　life…saving　regulation；　animals　under　stress　would　inevitably　commit　suicide；　and；　second；　that　it　is　probable　that　the　remarkable　phenomenon　of　anesthesia　the　coincident　existence　of　unconsciousness　and　lifeis　due　to　this　antithetic　action　of　the　cortex　and　the　medulla。

In　the　human；　as　in　the　animal；　the　degree　of　acidity　parallels　the　depth　of　inhalation　anesthesia。

Within　a　few　seconds　after　beginning　nitrous　oxid　anesthesia　the　acidity　of　the　blood　is　increased。　　This　rapid　acidulation　is　synchronous　with　almost　instantaneous　unconsciousness　and　increased　respiration。　If　the　oxygen　in　the　inhaled　mixture　be　increased；　a　decrease　in　acidity　is　again　synchronous　with　lighter　anesthesia　and　a　decrease　in　the　respiratory　rate。

If　these　premises　be　sound；　we　are　justified　in　asserting　that　the　state　of　anesthesia　is　due　to　an　induced　acidity　of　the　blood。　　If　the　acidity　is　slight；　then　the　anesthesia　is　slight　and　the　force　of　the　nerve　impulses　is　lessened；　but　the　patient　is　still　conscious　of　them。　As　the　acidity　increases　associative　memory　is　lost；　and　the　patient　is　said　to　be　unconscious：　　the　centers　governing　the　voluntary　muscles　are　not　inhibited；　however；　and　cutting　the　skin　causes　movements。　If　the　acidity　is　further　increased；　there　is　loss　of　muscular　tone　and　even　the　strong　contact　ceptor　stimuli　of　a　surgical　operation　do　not　cause　any　muscular　response；　and；　finally；　the　acidity　may　be　increased　to　the　point　at　which　the　respiratory　and　circulatory　centers　can　no　longer　respond　by　increased　effort；　and　anesthetic　death　that　is；　ACID　deathfollows。

Certain　clinical　phenomena　are　clarified　by　this　theory　and　serve　to　substantiate　it。　　For　example；　it　is　well　known　that　inhalation　anesthesia　precipitates　the　impending　acidosis　which　results　from　starvation；　from　extreme　Graves'　disease；　from　great　exhaustion；　from　surgical　shock；　and　from　hemorrhage；　and　which　is　present　when　death　from　any　cause　is　imminent。

We　see；　therefore；　that　anesthesia　is　made　possible；　first；　by　the　fact　that　inhalation　anesthetics　cause　acidity；　and；　second；　by　the　antithetic　adaptation　of　the　higher　centers　in　the　brain　and　of　the　centers　governing　respiration　and　circulation。

In　deep　contrast　to　the　action　of　inhalation　anesthetics　is　that　of　narcotics。　　Deep　narcotization　with　morphin　and　scopolamin　is　induced　slowly；　the　respiratory　and　pulse…rate　are　progressively　lessened　and　there　is　no　acidity。

By　our　researches　we　have　established　in　what　consists　the　generic　difference　between　inhalation　anesthetics　and　narcotics。　In　our　experiments　no　increase　in　the　H…ion　concentration　was　produced　by　morphin　or　by　scopolamin；　no　matter　how　deep　the　narcotization。　In　animals　already　narcotized　by　morphin　the　production　of　acid　by　any　of　the　acid…producing　stimuli　was　delayed　or　prevented。　　On　the　other　hand；　in　animals　in　which　an　acidity　had　already　been　produced　by　ether；　by　shock；　by　anger；　or　by　fear；　the　later　administration　of　morphin　delayed　or　inhibited　entirely　the　neutralization　of　the　acidity。　In　other　words；　morphin　interferes　with　the　normal　mechanism　by　which　acidity　is　neutralized　possibly　because　its　inhibiting　action　on　the　respiratory　center　is　sufficient　to　overcome　the　stimulating　action　of　acidity　on　that　center；　for；　as　we　have　stated；　the　neutralization　of　acidity　is　in　large　measure　accomplished　by　the　increased　respiration　induced　by　the　acidity　itself。


SUMMARY

Acidity　inhibits　the　functions　of　the　cerebral　cortex；　but　stimulates　those　of　the　medulla。　　This　antithetic　reaction　to　the　stimulus　of　increased　H…ion　concentration　is　an　adaptation　to　prevent　animals　from　committing　suicide　by　over…activity；　for　the　mechanism　for　the　initiation　and　control　of　the　transformation　of　energy　is　in　the　higher　centers　of　the　brain；　while　an　essential　part　of　the　mechanism　for　the　neutralization　of　aciditythe　centers　governing　circulation　and　respiration　is　in　the　medulla。　　This　explains　many　clinical　phenomena　why　excessive　acidity　causes　paralysis；　why　there　is　great　thirst　after　inhalation　anesthesia；　after　excessive　muscular　activity；　excessive　emotionafter　all　those　activities　which　we　have　found　to　be　acid…producing；　for　water；　like　air；　neutralizes　acids。　The　excessive　use　of　alcohol；　anesthetics；　excessive　work；　intense　emotion；　all　produce　lesions　of　the　kidney　and　of　the　liver。　The　explanation　is　found　in　the　fact　that　all　these　stimuli　increase　the　acidity　of　the　blood。　　and　that；　if　long　continued；　the　neutralizing　mechanism　must　be　broken　down　and　so　the　end…products　of　metabolism　are　insufficiently　prepared　for　elimination。

In　view　of　these　considerations　we　may　well　conclude　that　the　maintenance　of　the　normal　potential　alkalinity　of　the　blood　is　to　be　estimated　as　the　keystone　of　the　foundation　of　life　itself。



INDEX

ABDOMEN；　diseases　of；　phylogenetic　association　and；　44　Acidity；　227　Adaptive　energy；　176　variation　in　rate　of　energy　discharge；　177　Adrenalin；　Cannon's　test　for；　134；　196　injection　of；　changes　in　brain…cells　from；　186　Adrenals；　196　brain　and；　relation　of；　1。98　diseases　of；　effect　of；　on　output　of　energy；　216　functional　study　of；　196　histologic　study　of；　198　Alcohol；　changes　in　brain…cells　from；　116　Alkalescence；　227　Anemia；　pain　of；　77　Anesthesia；　2；　227　anoci…association　and；　differentiation；　34　effect　of　trauma　under；　upon　brain　that　remains　awake；　3　inhalation；　cause　of　exhaustion　of　brain…cells　as　res