Top Ten Reviews


Cognitive Function
 

Cognitive Function Introduction

Cognitive function describes a patient’s level of consciousness (sensorium), alertness, and orientation. Healthcare professionals measure cognitive function with the mental status examination, or MSE. According to The Merck Manual of Diagnosis and Therapy, the MSE evaluates cognitive function with the following standardized tests:

  • Memory and Orientation: tests immediate recall; memory for recent and past events; digit span; orientation to time, place, and person
  • Concentration: tests serial sevens (repeat 7 random digits forward and 4 in reverse order); months of the year in reverse order
  • General information: tests the Presidents, capitals, distances
  • Intelligence: tests compatibility of school and work records with current performance; interpretation of proverbs; general vocabulary; simple calculations
  • Insight and Judgment: tests with regard to present illness and future plans
  • Psychometric testing may be required

:cognitive.jpg Impairment in cognitive function can range in severity from short-term memory loss, to senility and dementia. An elderly person often experiences minor memory loss, which can result from normal brain aging. This should not be confused with dementia, the most serious cognitive impairment. Dementia marked by an often slow, or gradual process, which may take months or even years to become noticeable.

Dementia is a disease involving nerve cell deterioration and has accompanying symptoms that are severe enough to interfere with a person’s daily living. Severe symptoms often include memory loss with a combined decrease in cognition and the ability to reason. Alzheimer's disease is the most common cause of dementia.

However, not all cognitive impairments indicate the presence of Alzheimer’s disease. Cognitive impairment can occur at any age, and can result from many different disease processes. Other causes of cognitive impairment include; chronic inflammation of the cerebral blood vessels and brain cells, specific nutrient deficiencies, hormonal imbalances (especially DHEA, estrogen, testosterone), impaired circulation to brain cells (due to atherosclerosis, heart disease, poor health habits), essential fatty acid deficiencies, free radical damage, prescription drug side effects, elevated levels of MAO (monoamine oxidase), neurological disorders, and lowered levels of neurotransmitters (such as acetylcholine).

Cognitive Function Statistics

According to the U.S. National Center for Health Statistics (1):

  • Approximately 231, 900 nursing home residents had Alzheimer’s Disease in 1999
  • 58, 866 Americans died of Alzheimer’s Disease in 2002

Cognitive Function Symptoms

People of all ages may experience cognitive impairment such as short term memory loss due to other health conditions or problems. Again, elderly persons may experience minor memory loss as a normal part of aging. The symptoms of dementia are more serious and manifest, most commonly, within the elderly population. The symptoms of short term memory loss include:

  • Minor memory problems such as; difficulty remembering where objects are located, and forgetting people’s names, addresses, or telephone numbers.

The symptoms of dementia (such as Alzheimer’s disease) include:

  • Memory loss
  • Decrease in cognition
  • Decrease in the ability to reason
  • Unable to perform normal activities of daily living

Cognitive Function (Memory Loss) Treatment

Treatment varies according to either the severity of cognitive impairment, or the underlying health condition or problem that may be causing the condition. For instance, treatment of underlying health conditions may include; vitamin therapy for nutritional deficiencies, stopping prescription drugs that cause the cognitive impairment, and hormonal supplementation for hormonal imbalances. Drug therapy may also be implemented to enhance cognitive function.

Lifestyle changes can be made to improve overall health and help prevent or minimize age-associated cognitive impairment. Some ways to preserve cognitive function include regular exercise, abstaining from smoking, alcohol or drug use, mental exercises, obtaining a nutrient-rich diet, and adequate nutritional supplementation.

Supplements helpful for Cognitive Function

Vinpocetine

Vinpocetine, an extract derived from the periwinkle plant (Vinca minor), has been used in Europe for decades to treat brain circulation problems (2). Numerous studies show that vinpocetine supplementation can be useful in the treatment of cognitive impairments that are related to the aging process, while protecting against the effects of brain aging (2-9).

Glyceryl-phosphorylcholine (GPC)

Glyceryl-phosphorylcholine (GPC) is a nutrient precursor to the brain neurotransmitter acetylcholine. A recent medical review suggests that GPC supplementation may improve short-term memory and cognitive function, and protect against the effects of brain aging (10).



Coenzyme Q10

Coenzyme Q10 (CoQ10) boosts cellular energy production in the mitochondria, the cell’s energy powerhouse. One study has found supplemental CoQ10 acts as a brain cell energizer, and may protect against the effects of brain aging (11).

Essential Fatty Acids (Fish Oil)

The brain is almost entirely composed of essential fatty acids such as DHA and EPA. Studies have found that DHA is essential for normal brain function, and a deficiency of this nutrient can cause an overall decrease cognitive function (12). Supplementation with DHAs, such as fish oil, have been reported to improve memory, learning, and overall brain health (12, 13).



Vitamin B Complex

Elderly patients are often deficient in essential vitamins, especially in B complex vitamins. Several studies have shown that the supplementation with vitamins B6, B12, and folate (B9), improves cognitive function and memory impairment, and may be effective in treating dementia (14-16).



Antioxidants (Vitamins C, E, and Beta-carotene)

Vitamins C, E, and beta-carotene are potent antioxidants that help protect against free radical damage in the body, cognitive function impairments, and the effects of brain aging. Numerous studies indicate that supplementation with vitamins C, E, and beta-carotene improves cognitive function and may be effective in treating dementia (17-20).



Acetyl-L-Carnitine (ALC)

Acetyl-L-Carnitine (ALC) is a nutritional supplement with similar properties to the brain neurotransmitter, acetylcholine. One significant mammalian study reported that when older rats were fed ALC, age-associated cognitive impairment and mitochondrial decay in the brain was reversed (21). Other studies have shown that supplementation with ALC may be equally effective in treating Alzheimer’s disease (22-24).

Phosphatidylserine (PS)

Phosphatidylserine (PS), an essential component of brain cell membranes, enhances brain cell energy metabolism. Alzheimer’s patients often have abnormal PS. Studies have shown that supplementation with PS enhances cognitive function and memory, and may be effective treatment in those suffering from Alzheimer’s disease (24-26).

Ginkgo biloba

Ginkgo biloba, a botanical used for centuries for a variety of medicinal applications, has been shown to improve circulation and counteract age-related vascular disorders and dementia. Numerous studies have found that the oral supplementation with gingko can help protect against the effects of brain aging, enhance cognitive function, memory, and blood flow to the brain. Ginkgo biloba may also be an effective nutraceutical in treatment of Alzheimer’s disease (27-33).

References

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10. Parnetti et al., Treatment of cognitive dysfunction associated with Alzheimer’s disease with cholinergic precursors. Ineffective treatments or inappropriate approaches? Mech Ageing Dev. 2001 Nov;122(16):2025-40.

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20. Grundman M, et al. Vitamin E and Alzheimer disease: the basis for additional clinical trials. Am J Clin Nutr. Feb2000;71(2):630S-636S.

21. Liu J, Head E, Gharib AM, et al. Memory loss in old rats is associated with brain mitochondrial decay and RNA/DNA oxidation: partial reversal by feeding acetyl-L-carnitine and/or R-alpha -lipoic acid. Proc Natl Acad Sci U S A. 2002 Feb 19;99(4):2356-61.

22. Acetyl-L-carnitine. Altern Med Rev. Dec1999;4(6):438-41.

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