You are a research assistant helping a psychologist to examine the effects of vitamin E on memory. Discuss each of the following as it relates to this experiment:

a. the independent, dependent, and possible extraneous variables
b. how the extraneous variables will be controlled
c. how the experimental and control groups will be set up
d. whether a single-blind or double-blind experiment will be utilized
e. how the results will be measured

Answer will include that the independent variable would be the vitamin E, while the dependent variable would be the memory scores. Possible extraneous variables would include the personality, intelligence, and motivation of the subjects, which could be controlled by randomly assigning subjects to the experimental and control groups. Other variables, such as time of day and testing materials could be controlled by having the same environmental conditions and materials used with both groups. The experimental group would receive the vitamin E, while the control group would have to be given a placebo, since just taking a pill could affect the outcome. So, both groups will be given a pill. Most drug studies like this one are conducted in a double-blind, in which neither the subjects nor the experimenter with direct contact to the subjects knows which group is given vitamin E and which receives the placebo. The double-blind would prevent the experimenter with direct contact from giving a hint as to which group was given the active substance. For the results to be measured, both groups will have to be given a memory pretest to assess their memory before the experiment begins, since they would not come in with zero memory. So, a pretest memory span test would be given to both groups, then Drug A (vitamin E) will be given to the experimental group and Drug B (the placebo) will be given to the control group with a post-test memory span test being given at the end of the experiment. The difference between the two group, if any, would be measured with statistics being used to determine if the difference was statistically significant, which means that a difference must be large enough so that it would occur by chance in less than five experiments out of 100.