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From the Editor
Editor's Note
 
Memory News
Fatty food weighs down muscles and memory
 
Pumping Neurons: Exercise to maintain a healthy brain
The evidence is growing that moderate regular exercise boosts memory and other brain functions and may help prevent age-related declines.
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How Parkinsonís disease affects the mind

It’s not just a movement disorder. Besides causing tremors and other motion-related symptoms, Parkinson’s disease affects memory, learning, and behavior.

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Creative healing: art therapy for Alzheimer's disease and other dementias
As medical science races to cure dementia, storytelling and other creative activities promise a better quality of life for the millions already diagnosed.
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Memory Tip
Medicate Your Memory
Glossary
Bias
 

Bias refers to interference in a research study which can lead to misleading results.

One kind of bias is response bias: for example, patients who know they are being given a drug may often show improvement -- whether the drug itself is effective or not.

Another kind of bias is observer bias, an unconscious tendency for experimenters to find the results they expect. For example, suppose an experiment is conducted in which a number of patients are divided into two groups and given either a promising new drug or an inactive placebo (e.g. a sugar pill). If the experimenter knows which patients are in each group, he may quite unconsciously notice more signs of improvement in the drug group than in the placebo group. This will have the result of making the drug seem more effective than it really is.

A third kind of bias is selection bias: if the patients who are assigned to the drug group are less ill than the patients assigned to the placebo group, then the drug group will appear to reduce symptoms -- simply because those patients were less ill to begin with.

A third kind of bias is selection bias: if the patients who are assigned to the drug group are less ill than the patients assigned to the placebo group, then the drug group will appear to reduce symptoms -- simply because those patients were less ill to begin with.

Further Reading : "Putting Ginkgo to the Test"

by Catherine E. Myers. Copyright © 2006 Memory Loss and the Brain