It has been shown that the detection and discrimination of motion from random-dot kinematograms deteriorates with age. In addition to such low-level motion perception tasks, also the processing of more higher level motion stimuli, such as biological motion, changes with age; more specifically, it has been suggested that older adults rely more on the global form than the local motion information when processing point-light walkers (Pilz et al., 2010, Vision Research). Here, we investigated how the processing of local motion and form information in biological motion stimuli is related to sensitivity to coherent motion in healthy ageing. In a first task, we asked younger (18-32 years) and older participants (>60 years) to indicate the facing direction of three different point-light actions; normal actions that contained local motion and global form information, scrambled actions that contained primarily local motion information, and random-position actions that contained primarily global form information. In accordance with previous results, we found a general age-effect in that older adults performed worse than younger adults in all conditions. However, younger adults performed worse for random-position than normal actions, whereas older adults showed the same level of performance. Both age-groups performed worse for scrambled actions. In a second task, participants had to discriminate left/right (horizontal), or up/down (vertical) motion using random-dot kinematograms. We determined motion coherence thresholds for each participant using the method of constant stimuli with stimulus coherences varying between 1% and 80%. We found that overall, motion coherence was higher for vertical than horizontal motion but there was no difference in performance between age-groups. In addition, coherence thresholds did not correlate with performance in the biological motion task.
|Publication status||Published - 2015|
|Event||PSYPAG 2015 Annual Postgraduate Student Conference - Glasgow, United Kingdom|
Duration: 22 Jul 2015 → 24 Jul 2015
|Conference||PSYPAG 2015 Annual Postgraduate Student Conference|
|Period||22/07/15 → 24/07/15|