Brain training. The assessment of computerized braintraining programs is a rapidly growing area of research. Researchers are now focusing on who this training benefits most, what brain functions are most susceptible to improvement, and which products are most effective. A recent study looked at 487 community-dwelling adults aged 65 and older, each randomly assigned to one of two training groups. In one group, the participants used a computerized program 1 hour per day. In the other, DVD-based educational programs were shown and quizzes were administered after each video. The training period lasted 8 weeks.

The responsewas the improvement in a composite score obtained from an auditory memory/attention survey given before and after the 8 weeks.42 The results are summarized below.

Group n x s Computer program 242 3.9 8.28 DVD program 245 1.8 8.33

(a) Given that other studies have shown a benefit of computerized brain training, state the null and alternative hypotheses.

(b) Report the test statistic, its degrees of freedom, and the Pvalue.

What is your conclusion using significance level α = 0.05?

(c) Can you conclude that this computerized brain training always improves a person’s auditory memory/perception better than the DVD program? If not, explain why.