Anesthesia or hypesthesia is almost always inadvertently suggested by the physician’s examination. Seldom is sensory loss a spontaneous complaint, although “numbness” and paresthesias are not uncommon in hysterics. The sensory loss may involve one or more limbs below a sharp line (stocking and glove distribution), or may involve precisely one half of the body, or vibratory sense may be lost over precisely one-half of the skull (a test favored to demonstrate hysterical hemianesthesia). Touch, pain, taste, smell, vision, and hearing may all be affected on that side, which is an anatomic impossibility from a single lesion. Other aspects of psychogenic sensory disturbance are discussed in Chap. 8. The closest syndrome is that produced by a thalamic infarction but this, too, is easily distinguishable from psychogenic hemianesthesia.
The sometimes-stated notion that hysterical paralysis and sensory deficits are more common on the left side is untrue, according to Stone and colleagues (2002a).
The features of hysterical tremor and other movement disorders are described in Chap. 4. Emphasized here are the cessation of tremor with distracting tasks—for example, complex finger movement patterns on the side opposite the tremor (such as touching the fourth, second, and fifth fingers in sequence rapidly), or refixation of the eyes on a target, or walking on the outside of the heels. The ability of the examiner to “chase” the tremor to proximal or distal parts of the limb by holding and immobilizing one part is highly characteristic. A fairly dependable sign is worsening of a tremor with loading that is accomplished by placing a heavy object in the patient’s hand (most basal ganglionic and cerebellar tremors are muted by this maneuver).
Some general characteristics of psychogenic movement disorders that ring true to our experiences with patients are summarized in a review by Hinson and Haren; they include a typically acute onset and rapid progression of the movements, distractibility, variability and the simultaneous occurrence of various abnormal movements and of unexplainable paralysis, sensory loss, or pain. Needless to say the movements are not explainable by conventional characteristics of organic brain diseases, but as with all forms of hysteria, it is not on this feature alone that the diagnosis can rest. They point out, paradoxically, that an associated depressive or anxiety disorder is a good prognostic aspect.
Hysterical Blindness (See Also Chap. 12)
This dramatic event may affect one or both eyes and may be coupled with hemiparesis or appear in isolation. The symptoms usually develop suddenly, often after an altercation or other emotionally charged event. The patient stares straight ahead blandly when undisturbed, but may squint or move the head as if straining to see when asked to view an object. Some such individuals can reduce reflexive blinking in response to a visual threat. The psychic nature of the problem may be recognized by a nurse who observes the patient reaching for a cup or for the phone. The preservation of vision is confirmed by the presence of normal pupillary reflexes and of optokinetic nystagmus, although one occasionally encounters a patient who has learned to suppress the latter response as well. A mirror passed slowly in the patient’s central vision often engages eye movements. Other similar maneuvers are favored by different examiners. The presence of visual evoked responses also confirms the intactness of retinooccipital connections. The patient expresses little concern about the condition, which is usually short-lived. Cortical blindness and variants of the Balint syndrome are the main diagnostic considerations (see Chap. 21).
Convergence spasm, occurring as an isolated phenomenon, is practically always of hysterical nature. A related phenomenon involves the self-administration of mydriatic eyedrops by healthcare personnel. The patient arrives on the emergency ward complaining of reduced vision (expected) or with headache and claiming to have an intracranial mass. This behavior is perhaps more sociopathic (or malingering) than hysterical.