right|frame|Ivan Pavlov
'''Ivan Petrovici Pavlov''' (în limba rusă ''Иван Петрович Павлов'' * rus. I-a fost acordat condiţionării clasice în experimentele pe care le-a făcut cu câini.

==Viaţa şi activitatea de cercetare==
Pavlov s-a născut în Riazan, Rusia. Şi-a început studiile superioare ca seminarist, apoi a renunţat şi s-a înscris la Universitatea din Petersburg, pentru a studia ştiinţe naturale. A obţinut titlul de doctor în 1879.

thumb|250px|left|Câinele lui Pavlov, în muzeul Pavlov, 2005 În anii 1890, Pavlov a investigat funcţia gastrică a câinelui prin externalizarea glandei salivare pentru a putea colecta, măsura şi analiza saliva produsă ca răspuns la mâncare, în condiţii diferite. El a observat că aceştia au tendinţa de a saliva înainte ca hrana să ajungă în cavitatea lor bucală, şi a început investigarea acestei "secreţii psihice", cum a numit-o el.  A decis că aceasta este mult mai interesantă decât chimia salivei, şi a schimbat scopul cercetării sale, efectuând o lungă serie de experimente în care a manipulat stimulii care apăreau înainte de aducerea hranei. El a stabilit de aici legile fundamentale pentru apariţia şi eliminarea a ceea ce el denumea "reflexe conditionale" &mdash; adică, răspunsuri reflexe, precum salivarea, care nu apăreau decât condiţional, ca urmare a unor experienţe precedente ale animalului. Aceste experimente au fost efectuate în anii 1890 şi 1900, şi au fost puse la dispoziţia cercetătorilor occidentali prin traducerea unor experienţe individuale, dar au devenit disponibile în totalitate în limba engleză printr-o carte publicată în 1927.

Pavlov era obsedat de programul şi de obiceiurile sale de muncă. Obişnuia să ia prânzul exact la ora 12, se culca la aceeaşi oră în fiecare seară, îşi hrănea câinele la aceeaşi oră în fiecare noapte şi pleca din Leningrad în Armata albă &mdash; după aceea a suferit de insomnie.

Spre deosebire de mulţi oameni de ştiinţă pre-revoluţionari, Pavlov a fost respectat de guvernul sovietic, şi i s-a permis să îşi continue cercetările până la o vârstă înaintată. Pavlov însuşi nu avea o atitudine favorabilă faţă de Premiului Nobel era văzut ca un atu politic important, şi era puternic susţinut. După asasinarea lui Molotov, criticând persecuţiile în masă care au urmat, şi cerând rejudecarea unor cazuri ale unor oameni pe care îi cunoştea personal. Mai târziu în viaţă a fost în special interesat de folosirea condiţionării pentru a stabili un model experimental asupra inducţiei nerozei. A murit la Leningrad. Laboratorul său din Sankt Petersburg a fost păstrat până astăzi.

==Moştenirea==
În mod interesant, termenul lui Pavlov de ''reflex condiţional'' ("условный рефлекс") a fost tradus greşit din limba rusă ca ''reflex condiţionat'', iar alţi oameni de ştiinţă care au citit lucrările sale au ajuns la concluzia că dacă astfel de reflexe ar fi fost condiţionate, ar fi trebuit să fie produse printr-un proces denumit condiţionare. După ce munca lui Pavlov a devenit cunoscută în vest, în special datorită scrierilor lui John B. Watson, ideea de condiţionare ca o formă automată de învăţare a devenit un concept cheie în psihologia comparată, şi la referinţa generală la psihologie, behaviorismul.
Bertrand Russell a fost un avocat entuziast al importanţei lucrărilor lui Pavlov pentru filosofia minţii.  

Cercetările lui Pavlov asupra reflexelor condiţionale au influenţat puternic nu doar ştiinţa, dar şi cultura de zi cu zi. Termenul "câinele lui Pavlov" este adesea utilizat pentru a descrie o persoană care doar reacţionează la o anumită situaţie, în loc să folosească gândirea critică. Condiţionarea pavloviană a fost tema principală a romanului lui Brave New World''

Se crede de obicei că Pavlov anunţa aducerea hranei printr-un clopoţel, însă notiţele sale arată utilizarea unui număr mare de stimuli auditivi, incluzând fluiere, metronoame, împreună cu stimuli vizuali. În anii 1990, când savanţii occidentali au avut acces la laboratorul lui Pavlov, nu s-a găsit nici urmă de clopoţel.

==Vezi şi==
*Razan

''For other uses, see Pavlov (disambiguation).''
{{Infobox_Scientist
|name = Ivan Petrovich Pavlov<br />Иван Петрович Павлов
|image = Ivan Pavlov (Nobel).png
|image_width = 150px
|caption = Nobel Prize portrait, 1904
|birth_date = 
|birth_place = Russia
|death_date = 
|death_place = Leningrad, Soviet Union
|residence = Russian Empire, Soviet Union
|nationality = Russian, Soviet
|field = Physiologist, psychologist, physician
|work_institution = Military Medical Academy
|alma_mater = Saint Petersburg University
|doctoral_advisor =
|doctoral_students =
|known_for = Classical conditioning<br />Transmarginal inhibition<br />Behavior modification
|prizes =  Nobel Prize in Physiology or Medicine
|religion = Russian Orthodox
|footnotes =
}}
'''Ivan Petrovich Pavlov''' (, September 14, 1849 &ndash; February 27, 1936) was a Russian physiologist, psychologist, and physician. He was awarded the Nobel Prize in Physiology or Medicine in 1904 for research pertaining to the digestive system. Pavlov is widely known for first describing the phenomenon of classical conditioning.

== Life and research ==
Ivan Pavlov was born in University of Saint Petersburg to study the natural sciences. He received his doctorate in 1879.

In the 1890s, Pavlov was investigating the gastric function of dogs by externalizing a salivary gland so he could collect, measure and analyze the saliva and what response it had to food under different conditions. He noticed that the dogs tended to salivate before food coated with chili powder was actually delivered to their mouths, and set out to investigate this "psychic secretion", as he called it. 

He decided that this was more interesting than the chemistry of saliva, and changed the focus of his research, carrying out a long series of experiments in which he manipulated the stimuli occurring before the presentation of food. He thereby established the basic laws for the establishment and extinction of what he called "conditional reflexes" &mdash; i.e., reflex responses, like salivation, that only occurred conditionally upon specific previous experiences of the animal. These experiments were carried out in the 1890s and 1900s, and were known to western scientists through translations of individual accounts, but first became fully available in English in a book published in 1927.

Unlike many pre-revolutionary scientists, Pavlov was highly regarded by the Soviet government, and he was able to continue his researches until he reached a considerable age. Moreover, he was praised by Lenin and as a Nobel laureate.<ref name="Ivan Pavlov"></ref><ref>[http://wwwa.britannica.com/eb/article-5560 Ivan Petrovich Pavlov :: Opposition to Communism - Britannica Online Encyclopedia<!-- Bot generated title -->]</ref> 
thumb|Portrait by [[Mikhail Nesterov (1935).]]

After the murder of Molotov criticizing the mass persecutions which followed and asking for the reconsideration of cases pertaining to several people he knew personally.

In later life he was particularly interested in trying to use conditioning to establish an experimental model of the induction of Leningrad. His laboratory in Saint Petersburg has been carefully preserved as a museum.

Conscious until his very last moment, Pavlov asked one of his students to sit beside his bed and to record the circumstances of his dying. He wanted to create unique evidence of subjective experiences of this terminal phase of life. The great scientific courage of Pavlov is exhibited by this story: he tried to learn, and to increase knowledge of physiology, even on his deathbed.<ref>Chance, Paul. ''Learning and Behaviour''. Wadsworth Pub. Co., 1988. ISBN 0534085083. Page 48.</ref>

==Reflex system research==
Pavlov contributed to many areas of physiology and neurology. Most of his work involved research in conditioning and involuntary reflex actions. 
<!--thumb|One of Pavlov’s rats with a surgically implanted [[cannula to measure salivation, Pavlov Museum, 2005]]-->

Pavlov performed and directed experiments on digestion which earned him the 1904 Nobel Prize in Physiology and Medicine<ref>[http://nobelprize.org/nobel_prizes/medicine/laureates/1904/press.html 1904 Nobel prize laureates]</ref> Experiments included surgically extracting portions of the digestive system from animals, severing nerve bundles to determine the effects, and implanting fistulas between digestive organs and an external pouch to examine the organ's contents. This research served as a base for broad research on the digestive system.

Further work on reflex actions involved involuntary reactions to stress and pain. Pavlov extended the definitions of the four temperament types under study at the time: phlegmatic, choleric, sanguine, and melancholic. Pavlov and his researchers observed and began the study of transmarginal inhibition (TMI), the body's natural response of shutting down when exposed to overwhelming stress or pain. This research showed how all temperament types responded to the stimuli the same way, but different temperaments move through the responses at different times. He commented "that the most basic inherited difference. .. was how soon they reached this shutdown point and that the quick-to-shut-down have a fundamentally different type of nervous system."<ref>Rokhin, L, Pavlov, I & Popov, Y. (1963) Psychopathology and Psychiatry, Foreign Languages Publication House: Moscow.</ref> 

Carl Jung continued Pavlov's work on TMI and correlated the observed shutdown types in animals with his own introverted and extroverted temperament types in humans. Introverted persons, he believed, were more sensitive to stimuli and reached a TMI state earlier than their extroverted counterparts. This continuing research branch is gaining the name highly sensitive persons.

William Sargant and others continued the behavioral research in mental conditioning to achieve memory implantation and brainwashing (any effort aimed at instilling certain attitudes and beliefs in a person).

==Legacy==
Pavlov's term "conditional reflex" ("условный рефлекс") was mistranslated from the Russian as "conditioned reflex", and other scientists reading his work concluded that since such reflexes were conditioned, they must be produced by a process called conditioning. As Pavlov's work became known in the West, particularly through the writings of philosopher Bertrand Russell was an enthusiastic advocate of the importance of Pavlov's work for philosophy of mind.