Associations between genetic variations and global motion perception

Abstract

The cholinergic system is known to strongly modulate perceptual and cognitive processes, and the alpha7 subunit of the cholinergic nicotinic receptor (CHRNA7) is broadly expressed within the visual system. Here, we assessed whether genetic variations of the alpha7 subunit of the cholinergic nicotinic receptor gene (CHRNA7) affect coherent motion perception. Motion perception has been shown to decline with age, and it has previously been suggested that effects of genetic variations are magnified by age. Therefore, we tested both older (n=62) and younger adults (n=63). We found that motion coherence thresholds were significantly higher for older compared to younger adults, in accordance with previous studies. Interestingly, there was a strong relationship between variants of the SNP rs2337980 of the CHRNA7 and motion direction discrimination. In particular, participants carrying the TC genotype had considerably lower motion coherence thresholds than CC carriers. The effect of genotype did not interact with age. Our results show that genetic variations are associated with perceptual performance but are unlikely to explain age-related changes.

The optomotor response of aging zebrafish reveals a complex relationship between visual motion characteristics and cholinergic system

“…Our findings suggest that the performance increase due to cholinergic activation is specific to certain stimulus parameters (i.e., contrast) and age groups. Although these findings are in agreement with the behavioral studies on humans reporting that cholinergic transmission plays an important role in motion processing (e.g., Kunchulia et al, 2019), they also emphasize that there is a complex relationship between visual stimulation and cholinergic system during neural aging. In fact, previous studies on the primary visual cortex showed the ACh level significantly increases response gain in the contrast domain.…”

“…Surprisingly, despite the evidence demonstrating the various contributions of the cholinergic system to visual processes, its specific roles in age-related changes in visual motion perception have not been studied extensively. Using genetic variations in the alpha 7 subunits of cholinergic nicotinic receptor (CHRNA7), a recent study investigated the relationship between the cholinergic system in humans and agerelated changes in motion perception (Kunchulia et al, 2019). The behavioral findings suggest that genetic variations are associated with perceptual performance on direction discrimination, but these associations seem to be unrelated to age-related changes.…”