一天内挤出来的15页term paper。快疯了

（经常有人问，心理学是读什么的，我不知道怎么答你，自己看呗）

Ivan Pavlov: Does His Name Ring A Bell?

Ivan Petrovich Pavlov was a well-known physiologist and being acknowledged as the founder of Classical conditioning theory in 1927. He’s been awarded Nobel Prize on his research on conditioning, which is a form of unconscious learning that plays an important role in modern day behaviorism psychology. To acknowledge this historical figure, I would like to write about his biography, background, theory, and his influence to other psychologists in this paper.

Biography

According to Nobel Foundation (2014), Ivan Pavlov was born on September 14, 1849 at Ryazan, a city of Russia. He was the first child out of ten siblings. His father was a village priest and he was strongly influenced by his father’s religious practices. During his young age, Pavlov was highly interested in natural science and spending plenty of time in gardening and observing the environment. To understand more about the nature, Pavlov made a decision to pursue higher education in science field.

When Pavlov decided study physiology and chemistry, he faced a very painful struggle in between science and religion. His father who was a pious priest did not agree with Pavlov’s decision in pursuing science instead of religious career. Yet, Pavlov ignored the objections and left the seminary to study at St. Petersburg University in 1869.

He graduated from St. Petersburg University with outstanding record and received the Degree of Candidate of Natural Sciences in 1875. To fulfill his cravings for knowledge, he decided to pursue his studies at the Academy of Medical Surgery. In 1879, Pavlov completed the course and was awarded a gold medal. Since then, Pavlov’s been committed a fellowship with the Academy to continue his research work. Throughout the years, Pavlov did plenty of researches and published several theories that caused revolutionary changes in the aspects of physiology, neurology, and psychology.

Background and Zeitgeist

Ivan Pavlov is famous due to his classical conditioning theory that provided a clear explanation in human reaction and response toward a stimulus. Pavlovian theory is definitely epic and remarkable, but he couldn’t come with the theory out of nowhere at the first place. There were zeitgeists, influence, and inspiration from other aspects in order for him to carry out the Pavlovian conditioning theory.

He was inspired by Dmitry Ivanovich Pisarev, a famous social critic and writer in Russian. Pavlov admired his literacy skills and knowledge in natural science and biology. Pisarev’s idealistic and nihilistic attitude eventually induced Pavlov to give up in religion and put fully attention in science (Todes, 2002).

Besides, Pavlov’s physiology career was strongly inspired by Sechenov, to the extent Pavlov address Sechenov as “the Father of Physiology”. Sechenov had introduced electrophysiology and neurophysiology into Russian physiology aspect which been used widely by other physiologist including Pavlov. Pavlov used Sechenov’s electrophysiology (linking brain activity and electric current) concept in carrying out his researches. According to Ostrovsky (2009), Sechenov and Pavlov were the first scientists who figured out the relationship between brain physiological reaction and psychological activity, which created a remarkable impact in Russian physiology history. Yet, Pavlov managed to improvise the concept and carry out experiments to support the theory. He studied neuro-regulation which means the role of the brain in regulating physiological condition. For example, stomach secretes gastric juice when we are hungry and saliva gland secretes saliva when we sense the presence of food.

During Pavlov’s early career life as physiologist, he used to carry out researches on animals due to ethical qualities. There were plenty of researches done by Pavlov in investigating animal digestive reflex and eventually he published a book named “The Work of the Digestive Gland” in 1897. This book was the first physiological book narrated about how the psychological action affects the physiological reaction. Like a stone being tossed into a lake, the ripple eventually becomes a huge wave affecting the physiology field in Russia. It was considered as a huge breakthrough in physiological studies and psychological studies too.

In Pavlov’s book, he mentioned that the experiment was successful and the result was significant. In the experiment, Pavlov installed a salivary fistula onto a subject dog’s mouth. Fistula is a surgical method to expose certain part of a body to enable easier and clearer observation for the researchers. Pavlov received help from his colleague, D. D. Glinskii who is the developer of fistula technique (Gantt, 1995). Glinksi developed fistula in 1895, which can be considered as the zeitgeist for Pavlovian theory. Without fistula, Pavlov’s experiment will be extremely difficult to be executed. When fistula was installed, it leaves the subject dog a big hollow hole at the side of the mouth and the salivary gland exposed. Hence, whenever there was a salivation take place, Pavlov was able to see it clearly and measure it by attaching a funnel to the fistula. Pavlov concluded that “eating causes salivation to take place” as the “unconditioned reflex” at the beginning of experiment by measuring the amount of saliva collected. But then he realized that the subject dog produced saliva even though the food was not entering the mouth. The appearance or the presence of the food was enough to make the subject dog salivated. Pavlov concluded this reflex as “conditioned reflex” (Anrep, 1927).

Pavlov had an idea which was “if a dog recognizes food, can it recognize other stimulus as well?” He started to combine the beat of metronome and the feeding process in order to observe the response of the subject dog towards the stimulus. After several number of trials, the subject dog salivated even by hearing the beat of the metronome. Pavlov recorded it down and called it as a “conditioned reflex” too. He mentioned that a conditioned reflex can be formed using any external stimulus if the stimulus is associated with any unconditioned stimulus. The pairing process must be used regularly in order to maintain the activation of the conditioned reflex. When food was not presented for the first time, the subject dog was still salivating by merely hearing the beats of the metronome. Yet, the subject dog was not salivating anymore if several times of metronome beating were not associated with food. Pavlov named this phenomenon as “extinction of conditioned reflex” (Anrep, 1927).

Besides from dogs, Pavlov did his experiments on monkeys too. Subject monkey showed a similar result as subject dog, which both of the subjects can be conditioned and the conditioned reflex can be extinct if the conditioned stimulus was not presented. Pavlov decided to go further in his conditioning theory by investigating the reflexes of the monkey on differentiation of the stimulus. First, Pavlov set the metronome beats to 1.3 beats per second/78 beats per minutes and associated it to food. The subject monkey recognized the beats and be ready for feeding whenever it heard the metronome beat. When the metronome was set to 2.5 beats per second/150 beats per second, the subject monkey was not move at all.  Once the beat was set back to 1.3bps, the subject monkey became alert and ready. Pavlov concluded this phenomenon as “differentiation”, the ability to distinguish small changes of stimuli.

Unfortunately, Pavlov’s theory faced much opposition and criticisms because the experiments were only focusing on animals and animal intelligence level cannot be applied to human. Therefore, Pavlov decided to support his theory by using an orphan child as the subject of his experiment. The subject child was placed in lying position on the bed and a dispenser was placed above the subject mouth. The dispenser was loaded with small cookies and the wrist of the child was wrapped by a wristband. The wristband was connected to the researcher’s booth (which is invisible by the subject) and when the researcher stimulated the wristband, the dispenser dropped cookie into the subject child’s mouth. After a couple of conditioning process, the subject child learned that each time the wristband vibrates, a cookie will be dropped from the dispenser. Each time the wristband vibrates, the subject child opened his mouth to wait for the cookie dropped into his mouth even though there was no cookie. Also, subject child showed differentiation and extinction process similar as the subject dog and the subject monkey. Pavlov later published this experiment result and finally being accepted by public. Pavlovian theory later on being known as classical conditioning and being used widely in psychology and physiology field.

Emerging of Classical Conditioning Theory

Pavlov theory of classical conditioning is generally defined as a pairing of conditioned stimulus and unconditioned stimulus that can lead to the subject performing a conditioned response after several times of repetition (Anrep, 1927). This theory is being called as “classical” because Pavlov believed that every organism in the world including human learns through this method. It is the most essential way for survival and learning.

In Pavlov’s context, classical conditioning can be carried out in several ways as long as the essential elements (unconditioned stimulus - UCS, conditioned stimulus - CS, unconditioned response - UCR, conditioned response - CR) are applied. The most common way of learning is forward conditioning. Forward conditioning occurs when the CS appears earlier than US in order to have CR. For example, a researcher rings a bell first before giving the food to a subject dog. The bell as the CS comes first, and then the food as the UCS comes later. After several numbers of repetitions, the subject dog will still have the similar learning outcome, which is salivating whenever the researcher rings a bell. During the forward conditioning process, the CS and UCS can be either overlapped or not overlapped. Overlapped conditioning is known as delay conditioning when the US starts to kick in before even the CS ends. Non-overlapped conditioning is known as trace conditioning when the CS and UCS have a clear time interval in between. There is no difference in term of results between delay conditioning and trace conditioning except the time interval of CS and UCS. Pavlov also concluded that both of the CS and UCS can be presented at the same time in order to condition a subject. This method of conditioning is called as simultaneous conditioning. Pavlov used this in his classical conditioning experiment which giving the subject dog food at the same time activating the metronome.

There is another advanced conditioning method found out by Pavlov which is the higher-class conditioning. Higher-class conditioning is special and more complex because this process involved two CSs (Defryn, 2001). Usually subjects will have highly sensitive differentiation between two different stimuli, yet in higher-class conditioning enable the subjects to have more than one stimulus to have same response. For example, conditioning can be done by pairing of a can opening sound as CS and the food as the UCS for a subject cat to be alert. As soon as the subject cat heard the sound of can opening, it will be alert and ready to be fed. Higher-class conditioning is when the subject cat learned that the can opening sound is actually associated with the can opener which can be interpret as can opening sound is the CS1 and the can opener itself is CS2. After two stage of conditioning process have been done, the cat will now salivate to a can opener rather than the sound of can opening. Higher-class conditioning explains well about human’s complex reasoning skill because of stacking of different stimulus and responses at the same time.

Pavlov also explained that conditioning can be done without using a real stimulus too. By non-real stimulus means the stimulus can be replaced by time or interval. Within animal body (including human), there is a mechanism known as biological clock which controls the physiological activities in adapting changes on a daily or seasonal cycle. Temporal conditioning uses this biological clock to have the ideal CR (Kirkpatrick & Church, 2000). For example, a mother feeds her baby every 4 hours interval. As time goes on, the baby’s biological clock will be automatically adapt to the interval by producing gastric juice every 4 hours in order to prepare for digestive process. If the baby was not being fed during the time, the baby will feel hungry because his body was adapted to be fed every 4 hours interval. In a nutshell, the time interval acts as the CS and it interacts with biological clock within animal body.

Strength and Weakness

Besides from the theory itself, Pavlov explained that conditioning learning can be removed or extinguished too. When the learned behavior extinguished, the phenomenon is known as extinction of behavior. Hence, UCS cannot be totally removed if the researcher wants the learned behavior remains functioning in the subject. This theory is later on being strengthened and improvised by another behaviorist, B. F. Skinner.

Development of Pavlovian Theory

To improvise Pavlov’s theory and make it easier to be taught, Pavlov categories three fundamental element for the theory of reflexes: the principle of determinism, the principle of analysis and synthesis, and the principle of structure (Asratyan, 2001).

The principle of determinism is the motivation, impulse, and cause and effect of every action. Any living animal requires an actual motivation and purpose in order to achieve something. This principle has been used by different psychologist in developing theory of needs and motivation later on. The principle of analysis and synthesis is the process of destruct and construct a process into a whole new process. Lastly, the principle of structure is the distribution of the action of forces in space and the adaptation of the process to the structure (Asratyan, 2001). The development of these principles helped greatly towards the building-up of a scientific theory in medical field. Besides, it helps in discovering of laws governing the functioning of the organism.

To introduce more psychologists about Pavlov’s theory, Pavlov’s work has been translated into American English and later brought to American Psychological Association. According to International Encyclopedia of the Social Science (1968), John B. Watson and behaviorists in America were surprised by Pavlov’s work because he had discovered the relationship between psychological action and physiological reaction much earlier than the American behaviorist. Due to the completeness of Pavlovian theory, they decided to apply it in American behaviorism psychology. The implication of Pavlovian theory indicated the neobehaviorism era and Pavlov became one of the pioneers of behaviorism in America. Yet, there were several parts of Pavlov’s works had been changed and improvised by the American behaviorists. For example, Pavlov suggested that animal behavior process acts following the order of stimulus -> neural process -> response; meanwhile American neobehaviorist changed it into stimulus -> response.

In 1903, experiments done by Pavlov and his disciple displayed that conditioned reflexes take place in the cerebral cortex, which acts as the “prime distributor and organizer of all activity” of the organism and it is responsible for the regulating activity and equilibrium of an animal with its environment. In modern biology and anatomy, “the prime distributor and organizer of all activity” has been named as the central nervous system (CNS).  According to Teplov (1964), the basis of higher nervous activity (psychic activity such as thoughts and consciousness) in higher animals is conditioned reflexes formed in the higher centers of the central nervous system (in higher vertebrates and in man, predominantly in the cerebral cortex) in addition to complex unconditioned reflexes (instincts, emotions, and the like), that is, those forms of cerebral activity that arise mainly in the subcortical nuclei. Moreover, the cortex and the subcortical nuclei of the cerebrum, each with their specific functions, are in continual communication and interaction and work together as an integral mechanism. The basic physiological life-saving drives (hunger, sex, defense, and other motivations), which can be localized mainly in the subcortical centers, also serve as the basis for the formation of corresponding conditioned reflexes and thus are reflected in higher nervous activity as the product of the integral relationship between the cortex and the subcortical centers of the brain. Indirectly, Pavlov contributed his works in modern day biology too.

Pavlov’s Influence in Psychology and Biology Aspects

According to International Encyclopedia of the Social Science (1968), Pavlov’s theory has driven the field of psychology in 20^th century though he was not a psychologist or even a psychiatrist. A physiologist who came out with this idea was one of the developers of the behaviorism psychology and classical conditioning became the foundation of it. The diversity of psychology school of thoughts became much more intense during that time.

B. F. Skinner was the most influential behaviorist date back in 20^th century. He gave a systematic description of the manner in which environmental variables control behavior. He distinguished two sorts of behavior: respondent behavior and operant behavior. First respondent behaviors, which are elicited by stimuli and can be modified through respondent conditioning, which is often called "Pavlovian conditioning" or "classical conditioning". However, operant behaviors are different than respondent behaviors, meaning that initially they are not induced by any particular stimulus. Both of these sorts of behavior had already been studied experimentally, Pavlov was the one who did the experiment in investigating respondent behavior (classical conditioning) and Edward Thorndike who discovered the role of reinforcement and punishment in learning process. B. F. Skinner took inspiration from Pavlov and Thorndike, and then brought both of the theories under the same account – Behaviorism psychology.

Operant behaviors can be strengthened through operant conditioning/instrumental conditioning, which require an external reinforcement. Reinforcement, a key concept of behaviorism, is the primary process that shapes and controls behavior, and occurs in two ways, "positive" and "negative". According to Skinner (1938), positive reinforcement is the strengthening of behavior by the occurrence of some event (e.g., praise after some behavior is performed), whereas negative reinforcement is the strengthening of behavior by the removal or avoidance of some aversive event (e.g., opening and raising an umbrella over your head on a rainy day is reinforced by the cessation of rain falling on you). Both types of reinforcement strengthen behavior, or increase the probability of a behavior reoccurring; the difference is in whether the reinforcing event is something applied (positive reinforcement) or something removed or avoided (negative reinforcement). Punishment is the application of an aversive stimulus/event (positive punishment or punishment by contingent stimulation) or the removal of a desirable stimulus (negative punishment or punishment by contingent withdrawal). Though punishment is often used to suppress behavior, Skinner argued that this suppression is temporary and has a number of other, often unwanted, consequences. Skinner also agreed with Pavlov’s idea of extinction, which is caused by the absence of a rewarding stimulus eventually weakens behavior.

John B. Watson viewed Ivan Pavlov's conditioned reflex as primarily a physiological mechanism controlling glandular secretions. Through his behaviorist approach, Watson conducted research on animal behavior, child rearing, and advertising. To Watson (1924), behaviorism was a declaration of faith. It was based on the idea that a methodology could transform psychology into a science. He wanted to make psychology more scientifically acceptable. Watson became interested in the work of Pavlov and eventually included a highly simplified version of Pavlov's principles in his popular works, Little Albert experiment. The goal of the experiment was to show how principles of, at the time recently discovered, classical conditioning could be applied to condition fear of a white rat into "Little Albert", an 11-month-old boy. Later, in an attempt to see if the fear transferred to other objects, Watson presented Albert with a rabbit, a dog, and a fur coat. He cried at the sight of all of them. This study demonstrated how emotions could become conditioned responses and strengthened Pavlov’s idea of stimulus generalization.

Pavlov’s theory of higher nervous activity also inspired psychologist Hans Eysenck in developing the theory of the physiological bases of extraversion/introversion (Teplov (1964). This is principally due to Eysenck’s use of the Pavlovian concepts of excitation, inhibition, and equilibrium of cortical nervous processes. Eysenck hypothesized that extraversion-introversion is a matter of the balance of “inhibition” and “excitation” in the brain itself.  These are ideas that Pavlov came up with to explain some of the differences he found in the reactions of his various dogs to stress.  Excitation is the brain waking itself up, getting into an alert, learning state. Inhibition is the brain calming itself down, either in the usual sense of relaxing and going to sleep, or in the sense of protecting itself in the case of overwhelming stimulation. Someone who is extraverted, he hypothesized, has good, strong inhibition: When confronted by traumatic stimulation -- such as a car crash -- the extravert’s brain inhibits itself, which means that it becomes “numb,” you might say, to the trauma, and therefore will remember very little of what happened. The introvert, on the other hand, has poor or weak inhibition: When trauma, such as the car crash, hits them, their brains don’t protect them fast enough, don’t in any way shut down.  Instead, they are highly alert and learn well, and so remember everything that happened.  They might even report that they saw the whole crash “in slow motion!”  They are very unlikely to want to drive anytime soon after the crash, and may even stop driving altogether. This theory of extraversion/introversion is highly similar to Pavlov’s theory, but in more humanistic context.

Conclusion

Ivan Pavlov was an excellent Russia physio-psychologist who made a huge influence in different aspects of science. His research in theory of classical conditioning is a tough journey for him. Pavlov faced plenty of criticisms and oppositions from his religious father. Yet, he had successfully published his theory and became well-known in Russia. In the next ten years, his theory had been introduced to American Psychological Association and created revolutionary changes in behaviorism psychology. Bunch of well-known psychologist were inspired by Pavlov’s idea such as Skinner, Watson, and Eysenck. Until today, his theory is still standing and being the standard for behaviorism psychology school of thought. Lastly, I would like to thank Pavlov for his effort and hard work in psychology.

Reference

Anrep, G. V. (1927) Conditioned Reflexes: An investigation of the  physiological activity of thecerebral cortex,  Oxford University Press: Humphrey Milford,  UK

Asratyan, E. A. (2001) I. P. Pavlov: His Life and Work, p.155, University Press of the Pacific,     Honolulu, Hawaii

Defryn, M. (2001) Pavlov: Classical Conditioning. Massey University, University of New             Zealand

Gantt, W. H. (1995) Ivan Petrovich Pavlov. Encyclopaedia Britannica 15th ed.

"Ivan Pavlov - Biographical". Nobelprize.org. Nobel Media AB 2014. Web. 21 Nov 2015.             http://www.nobelprize.org/nobel_prizes/medicine/laureates/1904/pavlov-bio.html

Kirkpatrick, K. & Church, R. M. (2000) Stimulus and temporal cues in classical conditioning.       Journal of Experimental Psychology: Animal Behavior Processes, 26(2), DOI:             10.1037//0097-7403.26.2.206

Ostrovsky, M. (2009) Russia remembers the great scientists Sechenov and Pavlov, Voice of          Russia

"Pavlov, Ivan Petrovich." International Encyclopedia of the Social Sciences. 1968. Retrieved        November 22, 2015 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-      3045000916.html

Skinner, B. F. (1938) The Behavior of Organism: An Experimental Analysis, University of            Minnesota, Appleton Century Crofts, Inc. NY

Teplov, B. M. (1964) Pavlov’s Typology, Recent Theoretical and Experimental Developments      from the Laboratory of B. M. Teplov, Institute of Psychology, Moscow

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Watson, J. B. (1924) Behaviorism. New York: People’s Institute Publishing Company.