Heart rate changes after reinforcing brain stimulation in rats.
Science (New York, N.Y.)
|June 14, 1963
Summary
Brain stimulation affects heart rate, initially accelerating it. Reduced intervals reveal only acceleration, with varying effects on baseline heart rates depending on the stimulated brain region. Parasympathetic responses were not linked to brain stimulation reinforcement.
Area of Science:
- Neuroscience
- Cardiovascular Physiology
Background:
- Cardiac responses to brain stimulation are complex.
- Previous research suggests potential links between brain stimulation and autonomic nervous system activity.
Purpose of the Study:
- To investigate the cardiac responses to hypothalamic and septal stimulation.
- To analyze the effect of varying stimulation intervals on these cardiac responses.
- To determine if parasympathetic responses accompany reinforcing brain stimulation.
Main Methods:
- Electrical stimulation of hypothalamic and septal brain regions in animal models.
- Recording and analysis of polyphasic cardiac responses, including heart rate acceleration.
- Manipulation of interstimulus intervals during stimulation.
- Measurement of prestimulus heart rates to assess background levels.
Main Results:
- Cardiac responses were polyphasic, with an initial accelerative component.
- Decreasing interstimulus intervals resulted in only accelerative components.
- Septal stimulation decreased prestimulus heart rates, while hypothalamic stimulation had variable effects (increased or unchanged).
- No evidence supported the involvement of parasympathetic responses in reinforcing brain stimulation.
Conclusions:
- Hypothalamic and septal stimulation elicit distinct cardiac response patterns.
- Stimulation parameters significantly influence the observed cardiac and baseline heart rate effects.
- The study did not find support for parasympathetic activity during reinforcing brain stimulation.
