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Updated: Jul 13, 2026
Gaze in Action: Head-mounted Eye Tracking of Children's Dynamic Visual Attention During Naturalistic Behavior
Published on: November 14, 2018
Predictive tracking over occlusions by 4-month-old infants
Claes von Hofsten1, Olga Kochukhova, Kerstin Rosander
1Department of Psychology, Uppsala University, Sweden. Claes.von_Hofsten@psyk.uu.se
Insights
Infants visually track objects by predicting their motion, not just by time or visual cues. This predictive tracking, or
Area of Science:
- Developmental Psychology
- Cognitive Neuroscience
- Infant Perception
Background:
- Infants' ability to visually track objects is crucial for understanding their environment.
- Predictive eye movements, or saccades, are essential for maintaining continuous visual contact with moving objects.
- Previous research has explored infant object tracking, but the underlying predictive mechanisms at occluders remain unclear.
Purpose of the Study:
- To investigate the principles governing infants' predictive gaze shifts towards an occluded object's trajectory.
- To differentiate between time-based, visual salience-based, memory-based, and cognitive-based predictive tracking in infants.
- To determine if infants mentally represent object motion during occlusion.
Main Methods:
- Two experiments involved 16-20-week-old infants visually tracking a horizontally oscillating object passing behind a central occluder.
- Occluder width, oscillation frequency, and motion amplitude were systematically manipulated to vary occlusion durations (0.20–1.66 s).
- Infant eye and head movements, along with object motion, were recorded at 240 Hz to analyze gaze shift latencies and predictive behaviors.
Main Results:
- Infants (49% of passages) exhibited predictive gaze shifts to the occluder's exit side before object reappearance.
- Predictive gaze shifts were not solely explained by time since disappearance or occluder width.
- The latency of pre-reappearance gaze shifts was significantly influenced by the time of object reappearance and all manipulated factors (duration, frequency, amplitude).
Conclusions:
- Infants' predictive gaze shifts suggest an active cognitive representation of the occluded object's motion.
- The findings support the hypothesis that infants mentally track object velocity during occlusion.
- This indicates sophisticated cognitive abilities in young infants for predicting object trajectories.
Abstract:
Two experiments investigated how 16-20-week-old infants visually tracked an object that oscillated on a horizontal trajectory with a centrally placed occluder. To determine the principles underlying infants' tendency to shift gaze to the exiting side before the object arrives, occluder width, oscillation frequency, and motion amplitude were manipulated resulting in occlusion durations between 0.20 and 1.66 s. Through these manipulations, we were able to distinguish between several possible modes of behavior underlying 'predictive' actions at occluders. Four such modes were tested. First, if passage-of-time determines when saccades are made, the tendency to shift gaze over the occluder is expected to be a function of time since disappearance. Second, if visual salience of the exiting occluder edge determines when saccades are made, occluder width would determine the pre-reappearance gaze shifts but not oscillation frequency, amplitude, or velocity. Third, if memory of the duration of the previous occlusion determines when the subjects shift gaze over the occluder, it is expected that the gaze will shift after the same latency at the next occlusion irrespective of whether occlusion duration is changed or not. Finally, if infants base their pre-reappearance gaze shifts on their ability to represent object motion (cognitive mode), it is expected that the latency of the gaze shifts over the occluder is scaled to occlusion duration. Eye and head movements as well as object motion were measured at 240 Hz. In 49% of the passages, the infants shifted gaze to the opposite side of the occluder before the object arrived there. The tendency to make such gaze shifts could not be explained by the passage of time since disappearance. Neither could it be fully explained in terms of visual information present during occlusion, i.e. occluder width. On the contrary, it was found that the latency of the pre-reappearance gaze shifts was determined by the time of object reappearance and that it was a function of all three factors manipulated. The results suggest that object velocity is represented during occlusion and that infants track the object behind the occluder in their 'mind's eye'.
