Confusion

Confusion of a pathological degree, usually refers to loss of orientation (ability to place oneself correctly in the world by time, location, and personal identity) and often memory (ability to correctly recall previous events or learn new material). Confusion as such is not synonymous with inability to focus attention, although severe inability to focus attention can cause, or greatly contribute to, confusion. 

Together, confusion and inability to focus attention (both of which affect judgment) are the twin symptoms of a loss or lackof normal brain function (mentation) . The milder degrees of confusion as pathological symptoms are relative to previous function. Thus (for example) a mathematician confused about manipulation of simple fractions may be showing pathology which would not be diagnosable in a person without training in this area. Thus, as with the case of delirium, the minor degrees of pathological confusion cannot be diagnosed without knowledge of a person's "baseline," or normal, level of mental functioning.

Confusion may result from a relatively sudden brain dysfunction (see delirium). It may also result from chronic organic brain pathologies such as dementia. In either case, confusion is usually associated with some degree of loss of ability to focus attention, but (as noted) the association is not invariable, especially for lesser degrees of impairment.^{[citation needed]}

Many health problems may cause the syndromes of delirium or dementia. These syndromes may also occur together, and both of them usually include the symptom of confusion. Since mental function is extremely sensitive to health, the appearance of either a new confused state, or a new loss of ability to focus attention (delirium), may indicate that a new physical or mental illness has appeared, or that a chronic physical or mental illness has progressed (become more severe).

Confusion is a symptom, and it may range from mild to severe. The confused state may include jumbled or disorganized thought and unusual, bizarre, or aggressive behaviors. A person who is confused may have difficulty solving problems or tasks, especially those known to have been previously easy for the person and an inability to recognize family members or familiar objects, or to give approximate location of family members not present. As well, they may appear to be disoriented, drowsy, or hyperactive. In severe cases, the person may have hallucinations, feelings of paranoia, and a state of delirium.

New research is finding a link between Vitamin D deficiencies and cognitive impairment which includes memory loss and a foggy brain.