Sniffing the distance: Scents can make objects appear closer.

Judging distances between oneself and objects in the environment is vital. Such distance judgments are based mostly on visual cues. But can smelling an object also affect how close the object appears? Building on sensory distance theory, we suggest that scents can make objects seem physically closer. We investigate this effect across four studies (total N = 479) using a range of scents, objects, and distances. Leading to predictable estimation biases, the effect emerges regardless of scent salience and holds across different scent delivery modes: directly from an object (Study 1), surrogate via vial (Study 2 and 3), and ambient (Study 4). The biasing influence of scent persists even when the accuracy of estimates is incentivized (Study 2) and is stronger when cognitive resources are unconstrained (Study 4). While the effect emerges even when scents emanate from targets that are typically unscented (e.g., notepad; Study 1), it is attenuated when the scent is not associated with the target (Study 3). These findings highlight a novel role of scent in spatial cognition and hold implications for distance perception and distancing behaviors.