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H Bekkering

Publications and source records attributed to H Bekkering.

21 records · Page 2Linked to original sources

Motion thresholds of briefly visible stimuli increase asymmetrically with age.

During a pursuit eye movement made across a stationary stimulus, that stimulus is often perceived as moving slightly in the direction opposite to the eyes (Filehne illusion). The illusion is generally thought to increase in strength when the stimulus is made visible only briefly. In two experiments the illusion was indeed observed with young subjects. However, with older subjects brief stimulus presentations yielded a strong inverted Filehne illusion (the stimulus appeared to move in the same direction as the eyes). This age dependency of the Filehne illusion is caused by an increase of only the threshold for stimulus motion in the direction opposite to the eyes. No such effect happens with the threshold for stimulus motion in the same direction as the eyes. These findings can be explained if we assume that with increasing age it takes more time to properly register retinal image velocity within the perceptual system.

Adult↗

Influence of visual, vestibular, cervical, and somatosensory tilt information on ocular rotation and perception of the horizontal.

By combining a tilting chair and a tilting room we investigated the subjective horizontal (SH) and ocular counterrotation (OCR) as a function of body tilt, trunk tilt, and tilt of a visual frame. Significant influences of (isolated or combined) vestibular and visual information were found, but no influence of neck proprioception. A second and similar experiment, however, now conducted with subjects devoid of labyrinthine function, suggested a contribution of the neck as well as of somatosensory origin. This made a reinterpretation of our data for normal subjects possible.

Adult↗

Arthrokinetic information affects linear self-motion perception.

A sensation of linear self-motion can be induced in a blindfolded stationary sitting subject, who keeps contact with a linearly moving platform (acceleration 0.1 m/s2) in the frontoparallel plane by means of a hand-over-hand walking action. When discordant suprathreshold vestibular information from the otoliths is added by moving the subject laterally (acceleration 0.1 m/s2) in the same direction as the platform (acceleration of the platform 0.2 m/s2, so the arthrokinetic stimulus is also an acceleration of 0.1 m/s2, but into the opposite direction), the arthrokinetic information was found to have a predominant effect on the perceived direction of self-motion.

Humans↗