Wednesday, 01.04.2020

Thomas A. Ban
Neuropsychopharmacology in Historical Perspective
Education in the Field in the Post-Neuropsychopharmacology Era

Sechenov’s re-evaluation of mental faculties and the brain
(Bulletin 11)

 

Preamble:

This “vignette” is based, in part, on my notes on Ivan M. Sechenov while preparing, in the late 1950s for my dissertation entitled “Conditioning and Psychiatry” for a Diploma in Psychiatry, McGill University, Montreal, Canada.

 

Sechenov’s re-evaluation of mental faculties and the brain

         

          In 1669, John Locke (1632–1704), an English philosopher, published his classic, “An Essay Concerning Human Understanding” (4 books) in which he examined the foundation of human knowledge and understanding. In his treatise, Locke expressed his view that the mind at birth is a blank slate (usually referred to as tabula rasa) that is filled in later through experience and defined the self through a continuity of consciousness. It was also in this essay that Locke postulated the dependence of psychic activity on sense experience (Locke 1669; Wells 1959).  

             Ivan Mikhaylovich Sechenov (1829-1905) was a Russian physiologist who spent some time during his training in the laboratories of Johannes Peter Müller, in Berlin, and Claude Bernard, in Paris. Both Müller and Bernard were involved in research studying one or another aspect of “reflex activity” (see Bulletin 10).  While in Bernard’s laboratory, Sechenov was involved in research in which he succeeded in demonstrating “inhibition” of “reflex activity” (response) in frogs (Müller 1831;    Sechenov 1935; Wells 1956).

          In the early 1860s Sechenov went back to Paris to carry out further research to detect nervous centers which inhibit reflex movements. After completing his experiments, he wrote a treatise, “An Attempt to Establish the Physiological Basis of Psychical Processes,” that was published in 1863 with the title “Reflexes of the Brain.”  Central to Sechenov’s thesis was Locke’s premise that psychic activity was dependent on sense experience (Sechenov 1863, 1935; Wells 1956).

          Sechenov developed his argument about the physiological basis of psychic activity around the nature of the “reflex” by pointing out that a “reflex” has a three–phase structure. It is initiated in the first phase by a stimulus from the external or internal environment via sense receptors. It continues in the second phase by the transmission of the stimulus to the spinal cord or to the brain where connections and interconnections are made. It culminates in the transmission outward to the muscles leading to activity in the third phase. Every external activity is based exclusively on the muscles. Since the final manifestations of all psychical activity are expressed in muscular activity either by words spoken or written, or in deeds, all psychical phenomena can be explained by the activity of the nervous system and the brain. Words are a combination of sounds produced in the larynx and the cavity of the mouth by means of muscular movements (Sechenov 1935; Wells 1956).

          To pursue his argument further and apply it to the concepts of “faculty psychology” (see Bulletin 6), Sechenov was on less solid grounds and postulated the presence of centers in the brain, the function of which were to augment or inhibit the third or muscular phase of the reflex arc. With consideration of the activity of these centers, he accounted for “emotions” in terms of an augmented muscular response and “thought” by an inhibited muscular response. In a similar manner to “emotions” and “thoughts,” Sechenov attempted to account for all psychic phenomena, e.g., sensation, perception, will, wish, desire, memory, imagination (Sechenov 1935; Wells 1956).         

          In 1641, Rene Descartes (1596–1650), a French philosopher, published his treatise Meditationes de Prima Philosophia (Meditations on First Philosophy) in which he presented his doctrine on psychophysical parallelism by postulating that body and mind comprise a completely separate and materially unrelated systems which somehow run on parallel tracks (Descartes 1996). With the publication of “Reflexes of the Brain,” in 1863, Sechenov challenged Descartes’ doctrine.   For Sechenov, the soul, the psyche, was a function of the central nervous system in general and the brain in particular (Wells 1956).

          Sechenov’s contributions provide further elaboration of Wilhelm Griesinger’s (1843) “psychic reflex.” (See Bulletin 10). They also provide a bridge between the “psychic reflex” and Ivan Petrovich Pavlov’s (1849 -1936) “conditional reflex” (Ban 1964, 1966; Griesinger 1843).    

 

References

 

Ban TA. Conditioning and Psychiatry. Chicago: Aldine; 1964 and London: Unwin; 1966).

Descartes R. Meditations on First Philosophy, translated by John Cuttingham. Cambridge: Cambridge University Press; 1996.

Griesinger W. Über psychische Reflexaktionen. Mit einem Blick auf das Wesen der psychischen Krankheiten. Archiv für physiologische Heilkunde 1843; 2: 76-112.

 

Locke J. An Essay of Human Understanding. London: Thomas & Bessett; 1690

Müller JP. Bestätigung des Bell'schen Lehrsatzes, dass die doppelten Wurzeln der Rückenmarksnerven verschiedene Functionen, durch neue und entscheidende Experimente". Notizen aus dem Gebiete der Natur- und Heilkunde (Weimar) 1831; 113–7; 129–34.

 

Sechenov IM. Physiologische studien Ueber die Hummungsmechanismen fur die reflecthatigkeit des Ruckenmarks in Gehirne des Frosches und ueber die Elektrische und Chemische Reizung der sensiblen Ruckenmarksnerven des Frosches. In: Sechenov IM. Selected Works. Moscow: Foreign Languages Publishing; 1935. 

Sechenov IM Reflexes of the Brain. In: Sechenov IM. Selected Works. Moscow: Foreign Languages Publishing; 1935

Wells HK. Ivan P. Pavlov Toward a Scientific Psychology and Psychiatry. New York: International Publishers; 1956

 

March 29, 2018