Since approximately at the age of 10(I'm now 19), I have been able to voluntarily induce a complex physiological state involving multiple typically involuntary systems. This ability includes:

• Voluntary contraction of deep internal muscles, particularly in the abdominal and pelvic regions, creating strong muscle tension and spasms without external effort or cues.
• Conscious constriction of blood vessels and capillaries, primarily in my arms, legs, and genital area, resulting in pronounced visible veins and sensations of tightening or pressure within those areas.
• Modulation of heart rate, where I can seemingly slow my heartbeat during the muscle contractions and experience an increased heart rate or palpitations immediately after releasing the contraction. This effect is noticeable and sometimes accompanied by a feeling of dizziness or lightheadedness.
• Voluntary activation of the tensor tympani muscles in the ears, which produces a low-frequency, deep rumbling or “thunder” sound internally, audible only to myself. This is a rare phenomenon that I have not encountered in others.
• Pupil dilation during or immediately after the episode, which I can observe in a mirror, alongside rapid, shallow, or irregular breathing patterns that occur during or after the contraction period.
• A pronounced yawn reflex and fatigue immediately following the episode, suggesting some form of autonomic nervous system rebound or reset.
• Occasionally, this ability seems to spontaneously engage during extreme fatigue or stress, including during the transition to sleep, and can help me “wake up” from certain altered states of consciousness.

I am deeply interested in understanding the physiological, neurological, and possible autonomic nervous system mechanisms behind this voluntary control of typically involuntary functions. I would like to know how common or rare this ability is, whether it carries any health risks or benefits, and if there is any scientific literature or clinical research documenting similar cases. Additionally, I seek guidance on whether this ability can be safely trained or refined and if it might have implications for autonomic nervous system disorders or other clinical contexts.