In developing countries, domestic animals (eg, dogs) are common sources of infection. In the United States, bats and wild animals (eg, raccoons) are the most common reservoirs of infection. The acquisition of rabies from bats can occur from an unrecognized bite or a scratch, and possibly by inhalation of aerosolized viral particles. Bats are found in all states except Hawaii, and spelunking (cave exploration) is a risk factor for rabies acquisition from bats.

If you suspect that you have sleep apnea, the usual first step is to discuss your suspicions with your primary care physician. If you don’t have a primary care physician, you can go directly to a clinician who is a sleep specialist. But check your health care insurance coverage first. Some policies require you to see a primary care physician first, and some policies limit the sleep centers and testing facilities whose services they will pay for. Unfortunately, you may discover that your policy offers limited or no coverage for the diagnosis and treatment of sleep apnea, in which case you may wish to switch insurers if and when you can.

Narcolepsy is a chronic sleep disorder characterized by overwhelming daytime drowsiness and sudden attacks of sleep. People with narcolepsy often find it difficult to stay awake for long periods of time, regardless of the circumstances. Narcolepsy can cause serious disruptions in your daily routine. Sometimes, narcolepsy can be accompanied by a sudden loss of muscle tone (cataplexy) that leads to weakness and loss of muscle control. Cataplexy is often triggered by a strong emotion, most commonly laughter. Narcolepsy is a chronic condition for which there's no cure. However, medications and lifestyle changes can help you manage the symptoms. Support from others — family, friends, employer, teachers — can help you cope with narcolepsy.

Migraine headaches are recurrent throbbing or pulsatile headaches often associated with a prodrome, nausea, vomiting, photophobia, and phonophobia. When they occur, the prodromes are characterized by visual scintillations, scotomas, dizziness, or tinnitus

Holter monitoring, electrocardiogram or echocardiogram are only recommended if a cardiac cause (e.g., arrhythmias, possible cardiac syncope, myocardial ischemia) is suspected.

The "Get up and go" test is most commonly used to assess postural stability. In this test, the physician instructs the patient to stand up from a chair without assistance, walk a short distance, turn around, return, and sit down again. If the patient is unsteady or has difficulties during the test, further evaluation is necessary.

Vertebrobasilar insufficiency is typically secondary to emboli, thrombi, or arterial dissection. The labyrinth and brainstem are commonly affected, and symptoms may include vertigo, dizziness, dysarthria, diplopia, and numbness.

Cataplexy is a sudden, temporary loss of muscle tone that can result in collapse. It is often caused by intense emotions, including laughter

Panic attacks are discrete periods of intense fear or discomfort. Symptoms may include palpitations, sweating, trembling, shortness of breath, a choking sensation, chest pain, nausea, dizziness, paresthesias, and a fear of dying or losing control

demonstrates how the Epley maneuver is performed to treat POSTERIOR canal BPPV affecting the right ear. Animation showing what is going on within the inner ear is also shown in the 2nd half of the video.

Benign paroxysmal positional vertigo is an abnormal feeling of motion triggered by certain provocative positions. The condition is most often attributed to the presence of calcium debris within the posterior semicircular canal. Nystagmus is commonly seen

Labyrinthitis is a mild, often self-limited condition characterized by vertigo, tinnitus, nausea, and a loss of balance. The disorder often follows a viral illness (eg, influenza). Labyrinthitis may also be caused by trauma, bacterial infection, allergies, benign tumors, and certain medications .

Binswanger's disease is a type of vascular dementia that involves white matter infarcts. Patients with this disease usually present with apathy, agitation, and bilateral corticospinal or bulbar signs

This type of gait is most often seen in peripheral nerve disease where the distal lower extremity is most affected. Because the foot dorsiflexors are weak, the patient has a high stepping gait in an attempt to avoid dragging the toe on the ground.

The patient has spasticity in the lower extremities greater than the upper extremities. The hips and knees are flexed and adducted with the ankles extended and internally rotated. When the patient walks both lower extremities are circumducted and the upper extremities are held in a mid or low guard position. This type of gait is usually seen with bilateral periventricular lesions. The legs are more affected than the arms because the corticospinal tract axons that are going to the legs are closest to the ventricles.

Cerebral palsy refers to brain damage that occurs before a child is five years old. Therefore, adults cannot develop cerebral palsy. However, cerebral palsy does not get better or worse with age, so when a child has the condition, he or she will continue to have the condition into adulthood.

Scissor gait is a form of gait abnormality primarily associated with spastic cerebral palsy.

An epidural abscess is a collection of pus (infected material) between the outer covering of the brain and spinal cord and the bones of the skull or spine. The abscess causes swelling in the area. Spinal cord abscess (SCA) is a rare condition capable of causing permanent damage to the spinal cord. Abscesses are caused when injured tissue becomes infected. The body's immune system sends white blood cells to help fight off the infection. They begin to fill the damaged tissue, causing pus to build up.

Alcohol not broken down by the liver goes to the rest of the body, including the brain. Alcohol can affect parts of the brain that control movement, speech, judgment, and memory. These effects lead to the familiar signs of drunkenness: difficulty walking, slurred speech, memory lapses, and impulsive behavior.

-Korsakoff's syndrome is a common and preventable sequel of Wernicke's encephalopathy. Thiamine, if given during the stage of Wernicke's encephalopathy, can prevent the onset of Korsakoff's psychosis. The administration of glucose prior to thiamine can precipitate Korsakoff's syndrome, as seen in this case. In such patients, brain MRI frequently shows abnormal enhancement of the mammillary bodies & thallamus