Glass-cylinder-seeking rats

Although any form of an acquired drive is rooted in one of the innate drives, as soon as the new drive develops and operates in an inextinguishable manner, the roots become unrecognizable. Watching a glass-cylinder-seeking rat in operation, one cannot recognize that escape from a hot plate was the foundation of this acquired drive. 

The heat/pain stimulation via a hot plate at 60 °C confused some of the animals and, out of a group of ten, three died and one became ill (see Table 16 in Knoll 1969). Nevertheless, for producing glass-cylinder-seeking rats we used this temperature as it proved to be the most efficient. 

Fig. 4.2. Diagram of the setup used to analyze the behavior of glass-cylinder-seeking rats (see details in the text)...

The rat with the performance detailed in Protocol 1 behaved as usual on March 4 and 5. The duration of the first reaction, as always, was a longer one on both March 4 (12 01") and March 5 (10 27"). This is the characteristic warming up behavior of the glass-cylinder-seeking rats (see Knoll 1969, for review). A longer time is obviously needed until the state of enhanced excitability is reached in the proper group of cortical neurons which operate as the active focus, the cortical representation of the drive. 

We studied the appearance of this phenomenon on many well-performing glass-cylinder-seeking rats. We found that the rats lingered either at the start (Protocol 1 gives an example), hesitated to climb the rod (Protocol 2 provides an example), or were unwilling to jump onto the top of the glass cylinder (Protocol 3 furnishes an example). 

The long-term observation of the behavior of glass-cylinder-seeking rats convinced us that even a rat influenced by an acquired drive must be subject of a kind of psychic experience inseparable from emotions. This accords well with common experiences regarding the behavior of domesticated animals. We found convincing experimental evidence in support of this reasoning in a study by Phillips et al. (2003) on a peculiar form of goal-directed behavior performed by rats. 

In the most efficiently trained, best performing rats the acquired drive was so powerful that it suppressed even innate drives. When such a rat has been deprived of food for 48 h and then food was offered within the usual setup that contained the glass-cylinder, the rat looked for the glass cylinder and left the food untouched. Similarly, when a receptive female was offered to a sexually fully active glass-cylinder-seeking male rat in the usual setup, the male looked for the glass-cylinder and neglected the receptive female. 

An analysis of the ability of rats to acquire the glass-cylinder-seeking drive is another example that convincingly illustrates the great individual differences... 

We changed the environment after the 10th glass-cylinder-seeking performance. The plate from which the rat started to work and where the animal lingered for a long time was eliminated and the rat was placed directly on the bridge (A)... 

Protocol 3. Illustration of the typical behavior of a rat which acquired the glass-cylinder-seeking-drive within 58 days, being trained daily. The rat, whose training started on February 16, displayed the typical signs of boredom on July 18 for the first time. The protocol shows as examples the normal performance of the rat on April 25, the appearance of boredom, its elimination by changing the environment on July 18, and its return to the boring environment on September 17 ... 

It is a great pleasure to first of all mention my indebtedness to Karoly Kelemen and Berta Knoll (my wife), who entered my laboratory as students and were my only coworkers in the early 1950s when we learned to instill the glass-cylinder-seeking drive into the cortex of rats. This method allowed us to study the nature of an acquired drive and catalyzed my understanding of the crucial importance of this mechanism in the development of social life on earth. 

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