Memory Transfer Studies at the Institute of Experimental Medicine: History and Analysis of Methodological Errors
This paper analyzes a long-term study conducted at the Physiological Division of the I. P. Pavlov Institute of Experimental Medicine in Leningrad (St. Petersburg) and devoted to the so-called memory transfer, i. e. the search for a memory substrate among the protein (peptide) molecules produced in the nervous system in the course of learning. A brief history of this work is provided and the methodological errors and causes of failures and achievements are discussed. Before the beginning of these studies, it was known from the literature that a considerable number of memory transfer studies had been conducted using the complicated behavioral and conditioned reflex models. In the 1960s, numerous data was obtained concerned with memory transfer or the transfer of learning from one animal to another. George Ungar was the first to abandon the idea of ribonucleic acids being memory agents and proposed peptides for this role. Later on it was shown that the methodology used by Ungar to demonstrate direct transfer of information was incorrect. At the time, however, these failures were associated by some researchers with methodological weaknesses rather than with the essential impossibility of memory transfer. Ungar's theory became a groundwork on which the Physiological Division of the I. P. Pavlov Institute of Experimental Medicine based their search for the direct memory transfer molecules, using another model that was believed at the time to be devoid of the previous model's weaknesses. It was only after the results of these studies proved to be inconsistent with the basic hypothesis and thus became the reason for abandoning memory transfer studies that the question of the cause of failure was raised. When looking into why these studies failed, it was initially suggested that the model used in these experiments was wrong and could only demonstrate the modulation of already existing skill with donor material rather then the transfer of a new skill. Only later on, it became clear that the failure was not associated with the drawbacks in methodology. The problems arose from the fact that the task itself had been set incorrectly methodologically from the standpoint of a psychophysiological problem; the mental and physical planes were integrated incorrectly; and it was unclear how the authors understood the term “memory” and the transfer of what exactly they were studying. Additionally, the positive results of these studies are described. The paper provides a brief summary of data obtained in the course of these studies apart from the work conducted to identify the “memory molecules”, and valuable both experimentally and clinically.