Neural Stimulus
A neural stimulus is a hormone that is released by the glands of the endocrine system. This is a non-voluntary process in which the nervous system stimulates the endocrine system to release neural stimuli.
For example, when a stress response is needed the sympathetic nervous system stimulates the adrenal gland to release neural stimuli: adrenaline and noradrenaline (also known as epinephrine and norepinephrine). The types of stress situations which cause stimulation of the endocrine system and the subsequent release of neural stimuli are the 'fight or flight' response and conditions of physiological stress such as dehydration or dangerously low blood pressure.