One study found that familiar stimuli are often preferred to unfamiliar stimuli.

The findings suggested that the exposure to unfamiliar stimuli was correlated to avoidance behaviors.

The unfamiliar stimuli may lead to increased arousal and increased avoidance behaviors.

This analysis found that the effect is strongest when unfamiliar stimuli are presented briefly.

Discerning between familiar and unfamiliar stimuli allows for rapid threat appraisals in often hostile environments.

In reinforcer sampling, a potentially reinforcing but unfamiliar stimulus is presented to an organism without regard to any prior behavior.

Featural processing is much more commonly used with an unfamiliar stimulus or face.

External inhibition may be observed if a strong or unfamiliar stimulus is presented just before, or at the same time as, the CS.

To accomplish this, the design was required to have particular consideration as to how the robot would be able to interact with unfamiliar stimuli.

In this case the invader is an unfamiliar stimulus entering through the senses.