Consciousness requires wakefulness and awareness. Many neuropsychiatric syndromes involve the disturbance of these functions. This chapter provides an overview of the various clinical presentations involving quantitative or qualitative disturbances of consciousness in order to explore the associated pathologies and underlying neurophysiological mechanisms. It lays out a number of clinical syndromes associated with impaired consciousness, such as persistent vegetative state (PVS) or unresponsive wakefulness syndrome (UWS), where the patient’s bodily functions can continue independently and show activity in higher motor areas when prompted under functional magnetic resonance imaging, yet are unable to communicate or follow commands. Focus is then given to altered mental states where conditions, such as neuroleptic malignant syndrome (NMS), may cause patients to experience depersonalization, fugue states, and hallucinations. After exploring the neuroanatomy and neurophysiology of such disorders, with a description of the function and significance of the ascending reticular activating system (ARAS), a number of clinical scenarios are presented.
Adjusting the light in the limit conditions of consciousness by the means of ascending reticular activating system (ARAS) and of subordinated systemsPart 2: Continuation ^|^amp; Conclusion of the Article
