Proximal stimulus

In perception, the proximal stimulus refers to physical stimulation that is available to be measured by an observer's sensory apparatus. It can also refer to the neural activity that results from sensory transduction of the physical stimulation. The proximal stimulus is usually contrasted with the distal stimulus, which is the state of objects in the world that were the cause of the proximal stimulus.

Perception is sometimes described as the process of constructing mental representations of distal stimuli using the information available in proximal stimuli. For example, when a person "sees" a dog, it is because the dog (the distal stimulus) created a retinal image (the proximal stimulus) that was interpreted as a dog by the person's visual system.

The word proximal means "near". The proximal stimulus is the stimulus that is "near" to the observer, in other words, the stimulus that the observer can measure directly.