INSTRUMENTAL LEARNING OF HEART RATE AND BLOOD PRESSURE RESPONSES IN THE CURARIZED RAT

Abstract

The substantial experiments have shown that autonomic responses such as heart rate and blood pressure can be not only classically conditioned but also instrumentally established in the completely paralyzed and artificially respirated rats, to say nothing of the question whether the amount of changes of the responses caused by conditioning is more or less. Nevertheless, many theoretically and phenomenally unsolved issues remain in this kind of conditioning, and it is necessary that various studies should be done in the future to investigate and re-examine these problems. For years we have investigated primarily avoidance conditioning and operant conditioning of heart rate and blood pressure responses in the curarized rat. And we have confirmed that the animal could indeed learn to increase and decrease the heart rate and blood pressure in order to avoid and/or escape a painful electric shock and to obtain a reward of intracranial stimulation as described in Fig. 1 and 2. Now, to evaluate and provide a basic support for the clinical research we should have knowledge of the relationships among external stimuli, the brain and the internal organs. Learning paradigm can influence the observed behavior or a visceral organ in the following way : (1) through a learned skeletal response which is mechanically or chemically linked to the visceral organ, (2) through the mechanical or metabolic action of a learned skeletal response on the receptive field of an unconditioned autonomic reflex, (3) directly through the autnomic nervous system to the organ, and (4) directly through the autonomic nervous system and a particular skeletal response. Curare will block the visceral response in (1) and (2) but not (3). In case (4), if the skeletal response is primary and the innate connection is central, curare will not block the response. (for review, see Dworkin and Miller, 1976).