Inattentional

Inattentional is an adjective relating to inattention, especially the failure to notice unexpected objects or events when attention is focused on another task. In psychological literature, it is most often discussed in connection with inattentional blindness, a phenomenon in which people fail to perceive a salient item that is in plain sight because their attention is engaged elsewhere.

Inattentional blindness arises from the way attention selects information for conscious processing. Even though sensory input is intact, cognitive resources are allocated to a specific task, limiting awareness of other stimuli. Factors that influence the effect include the complexity of the primary task, the observer’s expectations, the salience of the unexpected item, and the observer’s goals or instructions. The phenomenon underscores that perception is not a passive process but an active, selective one.

Notable research includes the gorilla-in-the-mist study by Simons and Chabris (1999), in which participants counting basketball passes often failed to notice a person in a gorilla walking through the scene. Earlier work by Neisser and Becklen (1975) demonstrated that people could miss salient events when attention was divided between competing streams of information. These experiments illustrate that awareness can be highly dependent on where attention is directed, rather than on sensory limitations alone.

In everyday life, inattentional blindness has implications for activities demanding sustained attention, such as driving, medical screening, and aviation. It relates to but is distinct from change blindness, which concerns failures to notice changes in a scene, and from inattentive hearing, where important sounds are missed while focusing on another task.