Development of radial optic flow pattern sensitivity at different speeds

Abstract

The development of sensitivity to radial optic flow discrimination was investigated by measuring motion coherence thresholds (MCTs) in school-aged children at two speeds. A total of 119 child observers aged 6-16years and 24 young adult observers (23.66+/-2.74years) participated. In a 2AFC task observers identified the direction of motion of a 5° radial (expanding vs. contracting) optic flow pattern containing 100 dots with 75% Michelson contrast moving at 1.6°/s and 5.5°/s and. The direction of each dot was drawn from a Gaussian distribution whose standard deviation was either low (similar directions) or high (different directions). Adult observers also identified the direction of motion for translational (rightward vs. leftward) and rotational (clockwise vs. anticlockwise) patterns. Motion coherence thresholds to radial optic flow improved gradually with age (linear regression, p<0.05), with different rates of development at the two speeds. Even at 16years MCTs were higher than that for adults (independent t-tests, p<0.05). Both children and adults had higher sensitivity at 5.5°/s compared to 1.6°/s (paired t-tests, p<0.05). Sensitivity to radial optic flow is still immature at 16years of age, indicating late maturation of higher cortical areas. Differences in sensitivity and rate of development of radial optic flow at the different speeds, suggest that different motion processing mechanisms are involved in processing slow and fast speeds.

Concurrent Investigation of Global Motion and Form Processing in Amblyopia: An Equivalent Noise Approach

“…23 For example, some studies reported that the global motion processing mechanisms follow a long and protracted developmental pattern extending beyond 14 years. [51][52][53] However, there are other studies reporting a similar maturation age for both global form and motion processing. 54,55 Recent studies question the generalizability of dorsal stream vulnerability in neurologic developmental disorders.…”

Motion perception: a review of developmental changes and the role of early visual experience

“…More recent studies demonstrated adult-like thresholds only by mid-to-late childhood. Manning et al ( 2014 ) showed adult-like thresholds at the age of 9, Hadad et al ( 2011 ) found that thresholds were not mature until age 13, and Bogfjellmo et al ( 2014 ) and Joshi and Falkenberg ( 2015 ) showed maturation occurs even later (after the age of 14).…”

“…Narasimhan and Giaschi ( 2012 ) used three different densities of 1, 15, and 30 dots/deg 2 in an RDK paradigm and showed that in children, thresholds decrease as density increases for speeds of both 1 and 4 deg/s. Density rates vary across studies, ranging from 0.2 dot/deg 2 (Ellemberg et al, 2004 , 2010 ), 0.57 dot/deg 2 (Manning et al, 2014 ), 0.75 dot/deg 2 (Hadad et al, 2011 ), 1.1 dots/deg 2 (Meier and Giaschi, 2014 ), 2 dots/deg 2 (Joshi and Falkenberg, 2015 ), 3.8 dots/deg 2 (Bogfjellmo et al, 2014 ), 4 dots/deg 2 (Spencer et al, 2000 ; Gunn et al, 2002 ; Atkinson et al, 2003 ), to 32 dots/deg 2 (Parrish et al, 2005 ). This could account for the different developmental rates reported in the different studies.…”

“…Similar to Hadad et al ( 2011 ), their data did not show any difference between dots moving at 1.5 and 6 deg/s, presumably because of floor effect caused by the extremely low density of the display. Bogfjellmo et al ( 2014 ) demonstrated maturation at 14 years of age, using a density of 3.8 dots/deg 2 (although this late maturation may also be attributed to the difficulty in making clockwise/counterclockwise discriminations and to the low contrast stimuli), and Joshi and Falkenberg ( 2015 ) used density of 2 dots/deg 2 and found that sensitivity to radial optic flow is still immature at 16 years of age. Boot et al ( 2012 ) used a density of 2.6 dots/deg 2 and found adult-like performance relatively late, even when sensitivity was measured implicitly using ocular motor reaction time to fixation (Boot et al, 2012 ).…”

A probabilistic atlas of the human motion complex built from large‐scale functional localizer data

“…Finally, brain structure and function develop significantly from childhood to adulthood (Casey, Giedd, & Thomas, 2000;Giedd et al, 1999;Gomez et al, 2017). Although the developmental trajectory of the hMT+ is poorly known (Taylor, Olulade, Luetje, & Eden, 2018), behavioral studies have revealed that the ability for motion perception continues to develop until 14 years of age (Joshi & Falkenberg, 2015). The atlas presented in this study was constructed from young adults within a narrow range of age (mean = 20.31 years, SD = 1.26 years).…”