Which brain areas are linked to Hyperactivity in ADHD? I'm looking for some research identifying which brain areas or biological processes are behind specifically the hyperactivity symptoms of ADHD? I have done a preliminary search but most of the research I have found is about general ADHD symptoms/ how the brain of an individual with ADHD is different I'm struggling to find stuff focusing on the hyperactivity aspect.
I think the studies that you were after have only recently been published earlier this year. 38 subjects with ADHD had fMRI scans and compared with a database. The study found that - 


  More severe hyperactivity was associated with increased functional connectivity in the left putamen, right caudate nucleus, right central operculum and a portion of the right postcentral gyrus within the auditory/sensorimotor network.More severe hyperactivity was associated with increased functional connectivity in the left putamen, right caudate nucleus, right central operculum and a portion of the right postcentral gyrus within the auditory/sensorimotor network.
  https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-019-2031-9