| Cardiorespiratory |
| Increase in heart rate |
| Increase in blood pressure |
| Increase in respiratory rate |
| Fall in trancutaneous oxygen concentration |
| Sweat gland |
| Increase in palmar sweating |
| Increase in electrical conductance of the skin |
| Hormonal |
| Increased plasma concentrations |
| Cortisol Catecholamines |
| Renin activity and aldosterone |
| Growth hormone |
| Glucagon |
| Suppression of insulin secretion |
| Behavioural |
| Changes in facial expression |
| Onset and duration of crying (or in some cases, stopping of crying) |
| Flexor withdrawal of limb |