When the dog is repeatedly teased with the sight of objects inducing salivary secretion from a distance, the reaction of the salivary glands grows weaker and weaker and finally drops to zero.
Interpretation
This quote illustrates the concept of habituation, where repeated exposure to a stimulus reduces the response over time.
Ivan Pavlov's quote reflects his findings in classical conditioning and physiological responses, specifically how an organism's reaction diminishes when exposed to the same stimulus without reinforcement. In this scenario, the salivary glands of a dog eventually become less responsive to cues that previously triggered its salivation, highlighting the importance of consistency and expectation in learning and behavioral response.
In practice
In a psychology lecture about conditioning, you could use this quote to demonstrate how repeated exposures affect behavior.
If we could look through the skull into the brain of a consciously thinking person, and if the place of optimal excitability were luminous, then we should see playing over the cerebral surface, a bright spot with fantastic, waving borders constantly fluctuating in size and form, surrounded by a darkness more or less deep, covering the rest of the hemisphere.
From the described experiment it is clear that the mere act of eating, the food even not reaching the stomach, determines the stimulation of the gastric glands.
It is not accidental that all phenomena of human life are dominated by the search for daily bread - the oldest link connecting all living things, man included, with the surrounding nature.
Science demands from a man all his life. If you had two lives that would not be enough for you. Be passionate in your work and in your searching.
Learn the ABC of science before you try to ascend to its summit.
Do not become archivists of facts. Try to penetrate to the secret of their occurrence, persistently search for the laws which govern them.
The constancy of the internal environment is the condition for free and independent life: the mechanism that makes it possible is that which assured the maintenance, with the internal environment, of all the conditions necessary for the life of the elements.
The Soyuz craft weighs tons, and you're lying on the floor of it on your back. But the Russians do tell you, remember, before you land, stop talking so you don't bite your tongue off.
A study of Disease-of Pestilences methodically prepared and deliberately launched upon man and beast-is certainly being pursue in the laboratories of more than one great country. Blight to destroy crops, Anthrax to slay horses and cattle, Plague to poison not armies but whole districts - such are the lines along which military science is remorselessly advancing.
When we see the shadow on our images, are we seeing the time 11 minutes ago on Mars? Or are we seeing the time on Mars as observed from Earth now? It's like time travel problems in science fiction. When is now; when was then?
All models are wrong, and increasingly you can succeed without them.
[Decoding the human genome sequence] is the most significant undertaking that we have mounted so far in an organized way in all of science. I believe that reading our blueprints, cataloguing our own instruction book, will be judged by history as more significant than even splitting the atom or going to the moon.
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