Spread of inhibition across an object's surface

For efficient visual search it is critical that attention is inhibited from returning to previously examined loci. It has been demonstrated that this inhibition can be associated both with the location and the object towards which attention was oriented. However, it is not known whether, after attending to one part of an object, the inhibition spreads to the entire object, or remains localized at the attended site. This study demonstrates that inhibition can spread across an object's surface. This confirms that the presence of objects in a display is sufficient to observe an object-based inhibitory attentional effect. However, it is also noted that this spread of inhibition appears to decline with exposure to the task, being generally non-significant in the second half of the study. The study suggests that the magnitude of pure object-based Inhibition of Return (TOR) effect may be modulated by the subjective salience of the objects and that, when not directly relevant to a subject's behavioural goals, object-based representations can have minimal impact on attentional orienting processes.