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.Remarkably, he had the idea of the somatotopic organization of motorfunction in the cerebral cortex.He correctly localized control of the foot inthe dorsal cortex (he called it the  highest lobe ), the trunk in an intermediatesite, and the face and head in the ventral cortex (his third lobe):.the muscle and actions which are in the ultimates of the bodyor in the soles of the feet depend more immediately upon thehighest parts; upon the middle lobe the muscles which belong tothe abdomen and thorax, and upon the third lobe those whichbelong to the face and head; for they seem to correspond to oneanother in an inverse ratio.No other suggestion of the somatotopic organization of motor cortex appearsuntil the experiments of Fritsch and Hitzig in 1870.127 Chapter 3Further Insights into the Nervous SystemSwedenborg localized functions in addition to sensation and movement in thecortex.For example, he claimed that the anterior cortex is more important forhigher functions than the posterior38:If this [anterior] portion of the cerebrum.is wounded then theinternal senses imagination, memory, thought suffer; the verywill is blunted.This is not the case if the injury is in the backpart of the cerebrum.Frontal lesions are still considered to  blunt the will.Beyond the cortex, there are a number of other unusual insights aboutnervous function in Swedenborg s writing.He called the pituitary the  archgland.which receives the whole spirit of the brain and communicates it tothe blood. It was the  complement and crown of the whole chymical labo-ratory of the brain ; and the brain  stimulates the pituitary gland to pour outnew life into the blood. 39 Similar views of the pituitary do not appear untilthe twentieth century.Swedenborg s view of the circulation of the cerebrospinal uid was notsurpassed until the work of Magendie a 100 years later.40 He was the rst toimplicate the colliculi in vision,41 and in fact the only one until Flourens in thenineteenth century.He suggested that a function of the corpus callosum wasfor  the hemispheres to intercommunicate with each other. 42 He proposedthat a function of the corpus striatum was to take over motor control from thecortex when a movement became a familiar habit or  second Nature. 43Sources of Swedenborg s Ideas on the BrainWhere did Swedenborg s amazingly prescient views come from? Because of hisdetailed knowledge of contemporary brain anatomy and physiology, somehistorians thought that he must have visited brain research laboratories and there128 Emanuel Swedenborgcarried out dissections or participated in experiments.44 46 For example, he wasin Paris when Pourfour du Petit was conducting experiments on the effects oflesions of the cortex on movement in dogs.Thus, it was proposed that heparticipated in du Petit s experiments and might have observed the somatotopicorganization of motor cortex.Du Petit did realize that the cortex had motorfunctions, although his claims to this effect were ignored.47 However, there isno sign that du Petit himself had any notion of the topographic arrangementof motor cortex.Furthermore, Swedenborg s detailed travel diaries provide noevidence that he visited du Petit s or any other laboratory studying the brainduring his travels abroad.48 Visiting churches was more his wont.The available evidence indicates that Swedenborg s ideas came primarily,if not entirely, from a careful reading and integration of the anatomical,physiological, and clinicopathological literature that was available and that heso copiously quoted.49, 50 He paid particularly close attention to detailed de-scriptions and observations rather than simply to the authors own interpreta-tions and conclusions.Furthermore, he was unusual in attempting to integrateobservations of the effects of human brain injury with the details of comparativeneuroanatomy.Influence and Lack ThereofSwedenborg s writings on religion and spiritualism had an enormous impact onEuropean and American writers and artists.Blake, Yeats, Balzac, the Brownings,Beaudelaire, and Strindberg, for example, all claimed to be particularlyinuenced by him.51, 52 In nineteenth-century America his inuence was strongamong those interested in spiritualism and in transcendentalism.53 Ralph WaldoEmerson, who was involved in both, declared in 1854,  This age is Sweden-borg s.In spite of his fame in literary, artistic, and religious circles, or perhapspartly because of it, Swedenborg s ideas on the brain remained largely unknownuntil the twentieth century.The Latin originals of the Animal Economy booksof the 1740s were not even mentioned in the major physiology textbooks of129 Chapter 3the following decades, such as those by Haller (1754), Unzer (1771), Prochaska(1784), Blumenbach (1815), Magendie (1826), Bell (1829), or Mller (1840)English translations of Swedenborg that appeared in the 1840s do not seem tohave fared any better.They were ignored in the standard physiology textbooksof the day such as Carpenter s (1845) and Todd s (1845), and in Ferrier s (1876)monograph on the brain.Even one of the translators of The Animal Kingdom,J.J.G.Wilkinson, a London surgeon, hardly mentioned the brain in either hisbiography of Swedenborg or his commentary on The Animal Kingdom.54Early nineteenth-century reviews of Swedenborg s biological works werefew and puzzled.An Athenaeum reviewer in 1844 noted that The AnimalKingdom  will startle the physiologist and [contains] many assumptions he willbe far from conceding. 55 The most positive responses seem to have come frombooks on phrenology56 or mesmerism.57However, by the time the rst volume of The Brain was published in1882, the Zeitgeist had radically changed.Fritsch and Hitzig (1870) had dis-covered motor cortex, and the race to establish the location of the visual andother sensory cortices was well under way.Now Swedenborg s ideas on thebrain made sense, and both volumes received long rave reviews in Brain,58where the reviewer called it  one of the most remarkable books we have seenand noted that:.it appears to have anticipated some of the most moderndiscoveries [on the brain] but that because of its metaphysical,ontological, theological phraseology.if it had not been thatattention was arrested and enchanted by nding so many anticipa-tions of scientic discoveries by as much as 120 or 130 years, weshould have been tempted to throw aside the book as beyond ourprovince, if not hopelessly unintelligible [ Pobierz całość w formacie PDF ]

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