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41. Classical conditioning to hypercapnia in freely moving rats
Abstracts
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ly controlled breath. The role of muscular tensions in posture and respiration is reviewed, and the means and cases in which breathing therapy can be of help are discussed including the supposed corporal (sensorial) reasons for both hyperventilation and agoraphobia. 41. Classical conditioning to hypercapnia in freely moving rats Nsegbe, E.a, Vardon, G.b, Perruchet, P.b, Gallego, J.a “Facult& de Mddecine de Paris&d, bUniversitP de Picardie, France
France
Classical ventilatory conditioning refers to the fact that a stimulus (conditioned stimulus, CS) paired with hypercapnia or hypoxia (unconditioned stimulus, UCS) acquires the ability of eliciting a ventilatory response, as a consequence of the pairing. Conditioning must be assessed by comparing the ventilatory responses to the CS after the same number of paired or unpaired CS and UCS. Most animal studies on ventilatory conditioning lack this experimental control. We measured breathing variables in two groups of rats (Experimental, n = 9, and Controls, n = 7) using a whole body plethysmography. The UCS was an 8% CO, stimulus and the CS was a I-min tone. These stimuli were paired in the experimental group. In the control group, the UCS was delayed for 3 min from the onset of the CS. Each of the six successive phases comprised six paired-unpaired presentations of the UCS and CS, followed by one CS alone. The ventilatory responses to these latter CS served to test conditioning. The rates in the experimental group exhibited longer Tror (in about 15%) than controls following the CS at the end of acquisition. This conditioning effect was confirmed by a significant interaction term using phase as a repeated measure factor and group as a between-subject factor (F(5,70) = 3.48, P < 0.016). The fact that the conditioned response was opposite in direction to the hypercapnic response may be due to the mismatching between the anticipatory signal and the absence of hypercapnic stimulation when the CS is not followed by the UCS. The underlying process is not known. Alternatively, the decrease in frequency may be an avoidance response to limit aversive sensation provided by CO2 inhalation. This experiment confirmed the high sensitivity of breathing to conditioning, but it also suggested that ventilatory conditioning to exogenous CO, does not provide a suitable model of those processes actually occurring during exercise. 42. Treatment of repetitive strain injury (RSI) with respiratory sinus arrhythmia(RSA) training Pierce, L. Vancouver, B. C.. Canada
Repetitive strain injuries of the forearms appear to present at diagnosis in two subtypes: those which are definite overuse injuries to specific (often unilateral) anatomical structures at prime points of overload, compression or tension; and, those which
265
ly controlled breath. The role of muscular tensions in posture and respiration is reviewed, and the means and cases in which breathing therapy can be of help are discussed including the supposed corporal (sensorial) reasons for both hyperventilation and agoraphobia. 41. Classical conditioning to hypercapnia in freely moving rats Nsegbe, E.a, Vardon, G.b, Perruchet, P.b, Gallego, J.a “Facult& de Mddecine de Paris&d, bUniversitP de Picardie, France
France
Classical ventilatory conditioning refers to the fact that a stimulus (conditioned stimulus, CS) paired with hypercapnia or hypoxia (unconditioned stimulus, UCS) acquires the ability of eliciting a ventilatory response, as a consequence of the pairing. Conditioning must be assessed by comparing the ventilatory responses to the CS after the same number of paired or unpaired CS and UCS. Most animal studies on ventilatory conditioning lack this experimental control. We measured breathing variables in two groups of rats (Experimental, n = 9, and Controls, n = 7) using a whole body plethysmography. The UCS was an 8% CO, stimulus and the CS was a I-min tone. These stimuli were paired in the experimental group. In the control group, the UCS was delayed for 3 min from the onset of the CS. Each of the six successive phases comprised six paired-unpaired presentations of the UCS and CS, followed by one CS alone. The ventilatory responses to these latter CS served to test conditioning. The rates in the experimental group exhibited longer Tror (in about 15%) than controls following the CS at the end of acquisition. This conditioning effect was confirmed by a significant interaction term using phase as a repeated measure factor and group as a between-subject factor (F(5,70) = 3.48, P < 0.016). The fact that the conditioned response was opposite in direction to the hypercapnic response may be due to the mismatching between the anticipatory signal and the absence of hypercapnic stimulation when the CS is not followed by the UCS. The underlying process is not known. Alternatively, the decrease in frequency may be an avoidance response to limit aversive sensation provided by CO2 inhalation. This experiment confirmed the high sensitivity of breathing to conditioning, but it also suggested that ventilatory conditioning to exogenous CO, does not provide a suitable model of those processes actually occurring during exercise. 42. Treatment of repetitive strain injury (RSI) with respiratory sinus arrhythmia(RSA) training Pierce, L. Vancouver, B. C.. Canada
Repetitive strain injuries of the forearms appear to present at diagnosis in two subtypes: those which are definite overuse injuries to specific (often unilateral) anatomical structures at prime points of overload, compression or tension; and, those which