Final answer:
The response to a vague sense of threat or danger is known as the fight-or-flight response, involving physiological reactions to prepare for confrontation or escape triggered by the sympathetic system. While it was crucial for survival in the past, frequent activation due to modern psychological threats can lead to health issues.
Step-by-step explanation:
The physiological and emotional response to a vague sense of threat or danger is usually termed the fight-or-flight response. This response involves a set of reactions induced by sympathetic activity that prepares the body to either confront the threat or escape from it. In modern times, these responses are often associated with feelings of anxiety rather than immediate physical danger. For instance, the sensations experienced during public speaking or before an exam are related to the fight-or-flight response, triggered by perceived psychological threats.
The sympathetic system is responsible for these physiological responses to emotional states. The fight-or-flight response is a deeply ingrained reaction in humans and most mammals, part of our evolutionary heritage designed to ensure survival. However, in the modern world where threats are more psychological, frequent activation of this response can lead to negative health consequences such as increased risk of heart disease and compromised immune system function.