Pupil dilation is a common physiological response to stress.

Pupil dilation is a common physiological response to stress.

• A. True
• B. False
• C. Not enough information
• D. Depends on context

Answer: (A)

When the body encounters stress, the sympathetic branch of the autonomic nervous system is activated to prepare for a fight-or-flight response. A key effect of this activation is dilation of the pupils (mydriasis). Norepinephrine released to the iris dilator muscle causes the pupils to enlarge, which helps improve vision in potentially threatening situations by letting in more light and maximizing the field of view. This is a common sign of sympathetic arousal and is often seen with anxiety, fear, pain, or acute stress. Note that lighting can influence pupil size, but the stress response itself typically drives dilation as part of the body's rapid readiness to respond.

When the body encounters stress, the sympathetic branch of the autonomic nervous system is activated to prepare for a fight-or-flight response. A key effect of this activation is dilation of the pupils (mydriasis). Norepinephrine released to the iris dilator muscle causes the pupils to enlarge, which helps improve vision in potentially threatening situations by letting in more light and maximizing the field of view. This is a common sign of sympathetic arousal and is often seen with anxiety, fear, pain, or acute stress. Note that lighting can influence pupil size, but the stress response itself typically drives dilation as part of the body's rapid readiness to respond.