Stress

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Stress is the body’s biological and emotional response to demand — physical, emotional, cognitive, relational, or environmental. Feeling anxiety is one expression of a much broader brain–body shift. It occurs when the brain perceives something important is at stake and mobilizes the body to adapt. Mobilization can be helpful and protective, but can become destabilizing — especially in people with underlying biological vulnerabilities (such as heightened reward sensitivity or circadian fragility). For individuals with bipolar disorder, stress  can destabilize biological timing and reward systems that are already sensitive, increasing the risk of mood episodes. Stress activates multiple systems at once:

• Fight-or-flight response (FFR) of the autonomic nervous system
• Hormonal stress system (often called the HPA axis)
• Dopamine and reward pathways
• Inflammatory and metabolic systems
• Circadian timing system

Types of stress:

Acute stress is a short-term, intense physiological/psychological response to an event — negative or positive. The body surges with energy, attention sharpens, sleep may shift, and stress hormones rise. Acute stress is adaptive in the short run.

Episodic (repeated acute) stress consists of frequent bursts occurring close together. The system is repeatedly activated before it has fully returned to baseline. Over time, recovery becomes less complete. This pattern is destabilizing, particularly for people whose nervous systems are already highly reactive.

Chronic stress is a prolonged state of ongoing demand in which the stress system remains partially activated for weeks, months, or longer. The body adapts to a “new normal” of elevated stress signaling. This can alter sleep timing, energy regulation, immune function, and mood stability. More than feeling overwhelmed — it shifts baseline physiology.Stress is feeling anxious and distressed from challenging situations. Depending on the individual and how they handle stress, stress can trigger the fight-or-flight response (FFR)