zona incerta
The zona incerta is a horizontally elongated region of gray matter cells in the subthalamus below the thalamus. Its connections project extensively over the brain from the cerebral cortex down into the spinal cord. Its function is unknown though several have been proposed related to 'limbic-motor integration' such as controlling visceral activity and pain; gating sensory input and synchronizing cortical and subcortical brain rhythms. Its dysfunction may play a role in central pain syndrome. It is also been identified as a promising deep brain stimulation therapy target for treating Parkinsons Disease. Its existence was first described by Auguste Forel in 1877 as a 'region of which nothing certain can be said'. A hundred and thirty years later in 2007, Nadia Urbain and Martin Deschênes of Université Laval noted that the 'zona incerta is among the least studied regions of the brain; its name does not even appear in the index of many textbooks. ' [WP,unvetted].