Heritability of motor control and motor learning

Abstract

The aim of this study was to elucidate the relative contribution of genes and environment on individual differences in motor control and acquisition of a force control task, in view of recent association studies showing that several candidate polymorphisms may have an effect on them. Forty‐four healthy female twins performed brisk isometric abductions with their right thumb. Force was recorded by a transducer and fed back to the subject on a computer screen. The task was to place the tracing of the peak force in a force window defined between 30% and 40% of the subject's maximum force, as determined beforehand. The initial level of proficiency was defined as the number of attempts reaching the force window criterion within the first 100 trials. The difference between the number of successful trials within the last and the first 100 trials was taken as a measure of motor learning. For motor control, defined by the initial level of proficiency, the intrapair differences in monozygotic (MZ) and dizygotic (DZ) twins were 6.8 ± 7.8 and 13.8 ± 8.4, and the intrapair correlations 0.77 and 0.39, respectively. Heritability was estimated at 0.68. Likewise for motor learning intrapair differences in the increment of the number of successful trials in MZ and DZ twins were 5.4 ± 5.2 and 12.8 ± 7, and the intrapair correlations 0.58 and 0.19. Heritability reached 0.70. The present findings suggest that heredity accounts for a major part of existing differences in motor control and motor learning, but uncertainty remains which gene polymorphisms may be responsible.

Genetic basis in motor skill and hand preference for tool use in chimpanzees (Pan troglodytes)

“…Thus, we estimated the degree of genetic contributions to motor skill for the tool-use task, not the heritability in learning the task. Both motor learning and motor skill have been found to be heritable in humans [41]. To obtain such measures in chimpanzees or other nonhuman animals would require measures of both the acquisition and terminal motor performance on a novel motor learning task.…”

“…For instance, there is evidence of sex differences in tool use, with female humans reported to show better performance on fine motor tasks, whereas males perform better on tasks requiring more ballistic movements [38]. There is also a large body of data showing age-related changes in motor skill in humans [39], and there is evidence that tool-use learning and skill are both heritable [40,41].…”

Widespread Volumetric Brain Changes following Tooth Loss in Female Mice

“…However, these effects of tooth loss vary substantially across individuals (Haraldson et al, 1988; Zarb et al, 2013; Carr and Brown, 2015), both in terms of the type and severity of the outcomes, and also in the rate and quality of recovery. This suggests that while these traits are impacted by variable environmental factors, they may also be under genetic influences which are still unknown (Mishra et al, 2007; Seltzer and Mogil, 2008; Katz and Seltzer, 2009; Missitzi et al, 2013). Finding ways to prevent or treat tooth loss-induced impairments depends on knowledge of the involved genetic, cellular, molecular, structural, and functional brain mechanisms, which is currently largely lacking.…”

Anodal tDCS over the Primary Motor Cortex Facilitates Long-Term Memory Formation Reflecting Use-Dependent Plasticity

“…We used a double-blind within-subject cross-over design where subjects practiced ballistic thumb movements while either anodal tDCS or sham tDCS was applied during two separate sessions that were at least 3 months apart. The cross-over design was chosen to reduce the influence of inter-individual differences in ability to undergo practice related neuroplastic changes, which can vary substantially and might result from the genetic background of the individual [ 36 ] or previous motor experience [ 30 ].…”