Treatment of Schizophrenia and Other Psychotic Disorders by Electrical Stimulation and/or Drug Infusion
Publication Date: 2005-Jan-21
The IP.com Prior Art Database
Todd K. Whitehurst: INVENTOR [+2]
Applying electrical stimulation to the brain and/or introducing one or more stimulating drugs to the brain is used to treat schizophrenia and other psychotic disorders. At least one implantable system control unit (SCU) produces electrical pulses delivered via at least one electrode implanted in the brain and/or drug infusion pulses delivered via a catheter implanted in the brain. The stimulation is delivered to targeted brain structures to adjust the activity of those structures. In some embodiments, one or more sensed conditions are used to adjust stimulation parameters.
Background and Summary
Schizophrenia: Introduction and Epidemiology
Schizophrenia, a disease of the brain, is the most disabling and devastating psychiatric illness. Schizophrenia is characterized by a constellation of distinctive and predictable symptoms. The symptoms that are most commonly associated with the disease are called positive symptoms, which denote the presence of grossly abnormal behavior. These include thought disorder, delusions, and hallucinations. Thought disorder is the diminished ability to think clearly and logically. Often it is manifested by disconnected and nonsensical language that renders the person with schizophrenia incapable of participating in conversation, contributing to his alienation from his family, friends, and society. Delusions are common among individuals with schizophrenia. An affected person may believe that others are conspiring against him or her (called “paranoid delusion”). “Broadcasting” describes a type of delusion in which the individual with this illness believes that his or her thoughts can be heard by others. Hallucinations can be heard, seen, or even felt; most often they take the form of voices heard only by the afflicted person. Such voices may describe the person's actions, warn him or her of danger, or tell him or her what to do. At times the individual may hear several voices carrying on a conversation. Less obvious than the “positive symptoms”, but equally serious, are the deficit or negative symptoms that represent the absence of normal behavior. These include flat or blunted affect (i.e., lack of emotional expression), apathy, and social withdrawal.
The incidence is 0.5% to 1% in the general population, and more than 2 million Americans are afflicted with schizophrenia. If a parent or a sibling is schizophrenic, the probability of developing schizophrenia is approximately 10%. If both parents are affected, the probability is approximately 40%. If a non-identical twin is schizophrenic, the probability is 10-15%; if an identical twin is ill, the probability is 35-50%. Men and women are equally at risk for developing the illness. However, in those 16-25 years of age, schizophrenia affects more men than women, while in those 25-30 years of age, the incidence is higher in women than in men. 75% of persons with schizophrenia develop the disease between 16 and 25 years of age. Onset is uncommon after age 30 and rare after age 40.
The prognosis for schizophrenia is varied. Approximately 25% of people diagnosed with the disorder have 1 or 2 schizophrenic episodes, after which, the disease never recurs. Approximately 50% of people cycle back and forth between periods when they have symptoms and periods when they are symptom-free. The remaining 25% are chronic schizophrenics and almost always show some type of schizophrenic symptom; th...