Stimulus

Stimulus is a term used in psychology, physiology, and behavioral science to refer to an event or condition that provokes a specific reaction in an organ or tissue, or causes a living organism to react in a particular way. Stimuli can be internal or external. Internal stimuli are changes within the body, such as hunger or thirst, while external stimuli are changes in the environment, such as light or sound.

Types of Stimuli

There are several types of stimuli, including:

• Chemical Stimuli: These are changes in the chemical environment, such as changes in pH or the presence of certain molecules.
• Physical Stimuli: These are changes in the physical environment, such as temperature, pressure, or light.
• Biological Stimuli: These are changes in the biological environment, such as the presence of other organisms or changes in the organism's own body.

Response to Stimuli

The response to a stimulus is often a change in behavior or physiological processes. This can include changes in heart rate, breathing rate, or movement. The response to a stimulus is often mediated by the nervous system or the endocrine system.

See Also

• Sensory system
• Perception
• Reflex