Cognitive Impairment and Dementia

The term cognition is defined as acquiring knowledge and understanding through experience, thought, and the senses.  Cognitive impairment refers to a deficit in knowledge, thinking, or memory that is disabling or interferes with normal functioning.  Individuals can also have cognitive deficits that are weaknesses when compared to others or reflect declines from their previous abilities.  Elderly individuals may have age-related deficits that are not impairing.  Others may have inherited or acquired cognitive deficits, such as a learning disorder or attention deficit disorder (ADD).  

Mild Cognitive Impairment, or MCI, is a diagnostic term used to describe a measurable cognitive impairment.  The cognitive impairment may be present in one or more areas of cognitive ability.  Cognitive abilities are often grouped by domains of attention, memory, processing speed, language, visual spatial functions, sensory-motor functions, and executive functions.  Executive functions describe a range of abilities, including planning, organizing, sorting, abstraction, mental flexibility, and adaptability.  Individuals with MCI do not show significant decline in ability to carry out most normal functional activities, such as conducting basic financial matters, driving, maintaining hobbies and recreational pursuits, scheduling and keeping appointments, preparing meals, or interacting effectively in social situations.  If you have a diagnosis of MCI, it does not necessarily mean that it will get worse.  Sometimes the impairment can be linked to certain medications or problematic combinations of medications.  MCI can also result from metabolic and hormonal imbalances, infections, or vitamin deficiencies. When these are addressed,  MCI may revert to normal cognitive performance after the underlying medical problem is resolved.

Dementia refers to a more severe level of cognitive impairment.  It is defined by relatively severe impairment in at least two areas of cognition and significant loss of the ability to perform many daily functional activities independently.  The severe cognitive impairment is determined by a combination of exceptionally low scores, compared to expectation, on standardized tests of cognition, and by reported or demonstrated functional decline.  The term dementia is not equivalent to Alzheimer's.   Alzheimer's Disease is the most prevalent brain disease that leads to dementia in the elderly, but many other brain diseases and injuries can cause dementia as well.  For example, individuals may be diagnosed with dementia as a result of traumatic brain injury, stroke, cardiac arrest, severe breathing problems, or long term heavy alcohol use.  Other  brain diseases that may lead to dementia include cerebrovascular disease (CVD), Lewy Body Disease (DLB), Parkinson's Disease (PD), Frontal-Temporal Dementia (FTD), and Primary Progressive Aphasia (PPA),  to name a few.  Please refer to the Links and Resources section for more information concerning these different disorders, their relative rates of occurrence, and typical symptoms.