In line with this, comparable problems in motor timing should be observed in first degree relatives and might, therefore, form a suitable endophenotypic candidate.
In previous studies, we and others have shown that non-affected siblings have subtle problems, similar to their affected siblings, in motor timing, motor control, motor speed and variability, and speed of oculomotor control [ 33- 36], suggesting endophenotypes for ADHD may also lie inside the motor domain.
Using autocorrelation analyses on timing variables, we show that motor timing was event-based at slow tempi and emergent at faster tempi.
Here, we study the genetic architecture of the associations between intelligence, perceptual timing (auditory rhythm discrimination) and motor timing (finger tapping) in a large twin cohort.
This included timing problems with John William's musical score.
It may be hypothesized that timing functions may be deteriorated to a different extent in motor and non-motor timing, because in motor timing the underlying brain structures may be more demanding than in non-motor timing.
Biologically justified revisions to the model eliminate the timing problems.
However, performance in the TE-task was poor in pHDs, suggesting for "motor timing" deficits.
They distinguished between "motor timing" tasks for which the timing of the response itself provided the dependent measure of performance and "perceptual timing" tasks for which the time of the response was not important; on their account, reproduction, production and tapping tasks represent motor timing tasks whereas interval judgment and estimation tasks represent non-motor tasks.
