Abnormal Cognition

This step indicates that things have changed for the worse since a previous “baseline” level of cognitive ability was evident. This decline in cognition is what we mean by “abnormal cognition.”

Decline in cognitive ability may be difficult to measure with simple screening tests. Sometimes, a detailed neuropsychological evaluation is needed, or repeated testing over time may be needed to clarify that there really has been a decline. In some cases, the history can establish that cognitive deficits are Not Acquired.

Once the clinician is convinced that there has been a decline in cognitive function, the next step is to determine whether there are signs of functional impairment. Of course, cognitive decline implies a type of impairment in brain function. What we mean here by functional impairment is the loss or degradation of the ability to execute previous skills. Generally, Activities of Daily Living (ADLs such as eating, toileting, bathing, dressing, etc.) are less likely to be impacted in mild stages of Alzheimer’s. The first indication of functional impairment may be what has been called Instrumental ADL (IADL). IADL impairment may manifest as difficulty with very high level skills such as managing a business enterprise or stock portfolio, driving or traveling without difficulty, or mixing up banking and personal finances. Individuals at the mild stage of AD typically have IADL impairment only, and not ADL impairment.

If there is an indication of functional impairment, click Dementia to see next steps. Otherwise, click Mild Cognitive Impairment. If the individual has some "Other Major Neuropsychiatric Illness" such as depression or schizophrenia, they may also be excluded. Individuals who are concerned about cognitive deficits but who do not have clear deficits on testing, or who have only behavior changes, have what is now called Subjective Cognitive or Behavioral Impairment.