Corticobasal Degeneration( CBD): CBD is considered one of the“ parkinsonian” disorders, or“ parkinsonisms.” There are about a dozen such diseases, all of which produce some degree of slowness, muscle stiffness, balance problems, and sometimes tremor. Most people with CBD have these things, but in addition they have unusual difficulty performing complex limb movements such as cutting food, buttoning, or typing. There is often a tendency to hold part or all of a limb in a fixed posture called dystonia. There can also be very rapid, irregular, small movements of muscles called myoclonus. The unusual feature about CBD is that it is almost always very asymmetric, with one side affected much earlier and worse than the other. In half of people with CBD, it’ s the left, and in half, it’ s the right. The side affected has no relationship to the person’ s handedness.
As its name states, corticobasal degeneration is a loss of brain cells emphasizing the cerebral cortex and the basal ganglia. The cortex is the outer layer of the cerebrum, the gray matter where most thinking, speech, and sensory perception occur. The basal ganglia are also gray matter, but they’ re deeper in the cerebrum and coordinate movement. Basal refers to the base of the brain and the ganglia are collections of brain cells in one location devoted to a single purpose.
Custodial Care: Usually refers to care rendered in a skilled nursing facility. Custodial care does not require a licensed medical provider, such as a nurse or therapist.
Degenerative: Marked by or pertaining to deterioration; particularly, deterioration of the function or structure of tissue or changes from a higher to a lower or less functionally active form.
Delirium: A sudden and typically temporary state of confusion, agitation, lethargy, or alteration of sensory perception caused by a medical, as opposed to a psychiatric, condition. A few common causes of delirium are intoxications by alcohol or other chemicals, alcohol or drug withdrawal, concussions, brain infections, dehydration, insufficient oxygen supply to the brain, or a recent epileptic seizure. Delirium will usually resolve if the cause can be corrected.
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Delusions: Persistent, aberrant beliefs.
Dementia: A neurological condition characterized by a progressive decline in intellectual functioning, resulting in impaired judgment, memory, and abstract thinking; disorientation; and personality disintegration. Dementia may result because of various underlying conditions, including certain neurodegenerative diseases, such as Alzheimer’ s disease or Huntington’ s disease; brain injury or tumors; inflammation of the brain( encephalitis); successive strokes; or a condition known as normal-pressure hydrocephalus, which is characterized by enlargement of cavities( ventricles) of the brain, with cerebrospinal fluid( CSF) pressure at the upper end of normal. Dementia in PSP and CBD, if it does occur, does not feature the memory problem that is so apparent in Alzheimer’ s disease. Rather, the dementia of PSP / CBD is characterized by slowed thought, difficulty resisting impulses, and difficulty synthesizing several different ideas into a new idea or plan. These mental functions are performed mostly by the front part of the brain( the frontal lobes). In Alzheimer’ s, on the other hand, the problem is mostly in the part of the brain just above the ears( the temporal lobes), where memory functions are concentrated.
Differential Diagnosis: Distinguishing between two or more diseases and conditions with similar symptoms by systematically comparing and contrasting their clinical findings, including physical signs, symptoms, as well as the results of laboratory tests and other appropriate diagnostic procedures.
Dopamine: A chemical that serves as one of the brain’ s most widespread neurotransmitters. Neurotransmitters help relay messages from one nerve cell to another. Dopamine is especially important in relaying messages about movement. The most prominent brain area hosting dopamine neurons is the substantia nigra, which is affected in Parkinson’ s disease, PSP, CBD, and MSA. In all of these disorders, many areas of the brain that do not use dopamine are also affected, and none of these disorders affects all of the dopamine-producing areas.