Olfactory Nerve (Cranial Nerve I) See Chapter 19 . Optic Nerve (Cranial Nerve II) See Chapter 16, Chapter 43 . Oculomotor Nerve (Cranial Nerve III) Anatomy Paired oculomotor nuclei are located in the dorsal midbrain ventral to the periaqueductal gray…
Pain Transmission and Modulation as Related to Headache Headache arises from activation of pain-sensitive intracranial structures. In the 1930s, Ray and Wolff identified which intracranial components were pain sensitive and mapped the pattern of pain referral based on studies in…
Since antiquity, scientists, philosophers, writers, and religious scholars from all cultures and continents have repeatedly raised two fundamental questions—(1) what is sleep? and (2) why do we sleep?—without satisfactory answers. Some 2000 years ago, Lucretius postulated that sleep is an…
Seizures and Epilepsy Definitions Seizures are transient events that include symptoms and/or signs of abnormal excessive hypersynchronous activity in the brain ( ). The traditional definition of epilepsy required the occurrence of two unprovoked seizures. It is known that the…
Neurocutaneous disorders are congenital or hereditary conditions that feature lesions of both the skin and nervous system. Although each condition, or phakomatosis , is distinct and characterized by a unique pathophysiology, the concept of neurocutaneous disorders unifies those neurological disorders,…
Channelopathies are disorders caused by ion channel dysfunction. Because of the great diversity of ion channel proteins and their expression in different tissues, channelopathies comprise a wide variety of clinical diseases ( Table 98.1 ), the discovery of which helps…
It is important for the practicing clinician to make the distinction between the term motor neuron disease (MND) and motor neuron diseases (MNDs). The intention of the first term, coined by Brain in 1969, is to refer to a specific…
Movement Disorders and the Basal Ganglia Neurologists often equate movement disorders with disease or dysfunction of the basal ganglia, so no review of movement disorders would be complete without a discussion of these subcortical structures and their connections. In some…
Normal Aging and Mild Cognitive Impairment Normal Aging A cognitive continuum exists from normal aging through mild cognitive impairment (MCI) to dementia. This continuum is better understood when realizing that it occurs on a background of some degree of cognitive…
Prion (pronounced pree-ahn ) diseases (PrDs) are a group of uniformly fatal neurodegenerative diseases caused by the transformation of an endogenous protein, PrP (prion-related protein), into an abnormal conformation (misfolded protein) called the prion . The term prion is derived…