Poster No:
2457
Submission Type:
Abstract Submission
Authors:
Patricia Hoyos1, Anna Williams1, Edan Daniel-Hertz1, Sabine Kastner1, Jesse Gomez1
Institutions:
1Princeton University, Princeton, NJ
First Author:
Co-Author(s):
Introduction:
Does development of visuo-spatial attention result from local computations in the visual cortex? The human visual system contains what is referred to as the "dorsal stream", a collection of retinotopic regions that process the visual image and play a key role in our ability to deploy visuo-spatial attention. However, the structural and functional properties of dorsal stream development across childhood have never been mapped, perhaps due to the difficulty of running attention-based experiments on young children. Overcoming this hurdle, we created two novel, child-friendly videogames designed to quantify how visuo-spatial computations develop in the dorsal stream. Because we will be measuring from visual cortex, we can quantify for each voxel the portion of visual space to which the population of neurons responds to a stimulus (the population receptive field, pRF). Modeling the pRF as a gaussian circle, we can quantify a pRF's position and size, as well as quantify how these parameters change when visuo-spatial attention is moved to test the hypothesis that pRF's become increasingly dynamic with development.
Methods:
In the first game called "Cartoonotopy", participants fixate at the center of the screen as a colorful cartoon-filled sliding bar sweeps across the visual field. This allows us to map pRF's and delineate the borders of the visual field maps that comprise the dorsal stream (V1 to the IPS0-5 maps in the parietal lobe). In the second game, "gopheRField", participants fixate while gophers emerge randomly from a grid of holes spanning the visual field. In alternating blocks, participants attend to either the gophers or a central stimulus. This allows us to quantify how each voxel's pRF dynamically shifts in response to the allocation of visuo-spatial attention to the periphery.
Results:
Outside the scanner, in a group of adults we demonstrate the gopheRField game can replicate known processing differences across the visual field (eccentricity and upper v. lower visual field effects), offering evidence that it is a tool sensitive to measuring visuo-spatial processing. We next performed functional MRI while participants played the gopherfield game to model pRF dynamics of the dorsal stream. In n=16 adults (mean age of 33.6), we find that the allocation of attention to the periphery significantly increases the size of pRF's particularly in higher-order regions of the dorsal stream such as IPS1-3 (pRF size center vs. peripheral condition; IPS1 p<0.05; IPS2 p<0.005; IPS3 p< 0.0005). Additionally, pRF's shift location and sample more eccentric portions of the visual field (IPS1-3 p's<0.005). However, pRF parameters were stable and not significantly different between conditions in areas of early visual cortex such as V1-V3.
We additionally collected data from n=5 (mean age of 10.6) children to evaluate developmental effects on pRF dynamics. Contrary to adults, pRF's of IPS1-3 did not show any significant changes between central and peripheral conditions. Instead, we found a significant age group effect on receptive field eccentricity in V2d (p<0.001), with children's V2d receptive fields shifting 0.6 degrees more than adults on average. These results suggest that the dorsal stream is undergoing development and earlier areas in the dorsal stream may be compensating for the higher-order area's protracted development.
Conclusions:
These data explicate the potential neural correlates of previous behavioral works showing that visuo-spatial attention undergoes protracted development. This developmental trajectory impacts the acquisition of skills that heavily rely on visuo-spatial attention, like reading (Hoyos et al., 2020). By studying the development of the attention network, we will provide useful benchmark data for future studies in children with ADHD and dyslexia, offering translational insight as to why there is a high comorbidity between the two disorders.
Lifespan Development:
Lifespan Development Other 2
Perception, Attention and Motor Behavior:
Attention: Visual 1
Perception: Visual
Keywords:
Cognition
Cortex
Development
FUNCTIONAL MRI
Perception
Other - Attention; Visuo-Spatial Attention; pRF mapping
1|2Indicates the priority used for review
Provide references using author date format
Hoyos, P. M. (2021), 'Development of spatial biases in school‐aged children', Developmental Science, vol. 24, no.3, pp. e13053