Animal experiments are a common method used in psychology to study the effects of extreme stress. Here is how researchers use animal models to study the effects of extreme stress: **Why use animal models? ** Using animal models allows researchers to control experimental conditions, manipulate stress levels, and study adaptive and maladaptive physiological and psychological responses. This is difficult to achieve in humans, who have complex social, emotional, and life experiences that make scientific control difficult. **Commonly used animal models:** 1. **Rodents**: Rodents, such as mice and rats, are the most commonly used animal models to study the effects of stress. They are relatively cheap, easy to handle, and have a relatively short lifespan, which makes them ideal for long-term studies. 2. **Dogs**: Dogs are also used in stress research, especially to study social stress and canine behavior. 3. **Non-human primates**: Non-human primates, such as rhesus monkeys and macaques, are used to study the effects of stress on behavior and physiology, especially when there are similarities between primates and humans. **Testing extreme stress with animals:** 1. **Unpredictable or predictable stress**: Researchers can create unpredictable stressors, such as sudden loud noises, or predictable stressors, such as timed electric shocks. 2. **Increasing intensity or duration**: Gradually increasing the intensity or duration of a stressor can help study the limits of an animal's response. 3. **Social stress**: Exposing animals to social stressors, such as confrontation or competition, can help study stress responses to social interactions. 4. **Long-term or repeated exposure**: Animals can be exposed to stressors for a long time or repeatedly to study the effects of continuous or repeated stress. **Measurement methods:** 1. **Physiological indicators**: Heart rate, blood pressure, cortisol levels, and other physiological indicators can measure an animal's response to stress. 2. **Behavioral observation**: An animal's behavior, such as eating, activity, or social behavior, can be monitored after stress is induced. 3. **Cognitive tasks**: Animals can participate in cognitive tasks, such as mazes or problem solving, to assess the effects of stress on cognitive performance. **Application of research results:** Studying the response of animals to stress allows scientists to: 1. **Understand the basic mechanisms of stress**: Animal research helps to reveal the effects of stress on behavior, physiology, and cognitive performance. 2. **Develop interventions**: Studying the effects of stress on animals can provide reference for the development of stress management strategies for humans, such as relaxation techniques or psychotherapy. 3. **Improve animal welfare**: Animal research can also provide reference for maintaining the welfare of animals in human care, such as in zoos or laboratory settings. Remember that animal research should follow ethical guidelines and be approved by the Institutional Animal Care and Use Committee (IACUC) to ensure animal welfare.