1. The research was about the effects of caffeine on brain development of a rat relative to that of adolescents.
2. The article states that they had a sample population of 28 male Sprague Dawley rats. The rats were 23- 25 days old; chosen at random.
3. The population could have consisted of male and female samples in order to better represent the broad teenager population.
4. Subjects were selected by their age. The rats had to be 23 to 25 days old with brain activity resembling the beginning of puberty in humans.
5. Yes there was a control group. There were 17 rats assigned to the control group by epoch scores exhibiting the highest wave activity at the beginning of the light period.
6. The independent variable was coffee.
7. The dependent variable was wave activity while sleeping and maturational markers.
8. The extraneous variables identified were the sleep/wake regulation. They manipulated this by administering caffeine via drinking water for 5 consecutive days.
9. They found a bias in the fact that data collection started immediately after surgical termination with no recovery period. They did not expect any post surgical effects but they cannot exclude any impact the surgery may have increased a portion of the wave activity.
10. Yes, conclusions were based on wave activity during sleep/activity and cortical maturation during a critical developmental period.
11. Their research would have been more thorough had they found correlations between structural findings and sleep changes. A larger sample was also needed in order find correlative evidence. Lastly, recovery time from surgery may have also improved the research.
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