Arousal is associated with functional brainstem neuron populations projecting to both thalamic and cortical neurons.[6] Therefore, the assessment of reflexes (Using the Glasgow Coma Scale) is important to investigate the functional integrity of the brainstem. Awareness is thought to be related with functional integrity of the cerebral cortex and its subcortical connections. The most important point regarding the classification of disorders of consciousness is, that consciousness cannot be measured objectively by any machine, although many scoring systems have been developed for the quantification of consciousness and neuroimaging techniques are important tools for clinical research, extending our understanding of underlying mechanisms involved.[7] Disorders in consciousness represent immense social and ethical issues because the diagnosis is methodologically complex and needs careful interpretation.