Questions:
1. What question or hypothesis was being tested in this research?
2. Describe the three conditions (groups) to which different subjects were exposed.
3. Why was each of these three groups necessary to test the research question?
4. Identify the independent and dependent variable.
5.Explain how this research was a double-blind study.
6. Why did the researchers include a questionnaire to determine age, weekly exercise, tobacco use, and use of oral contraceptives?
7. Describe what is revealed in the graph titled Figure 1.
8. What is meant by a placebo effect? What do the authors conclude about a possible placebo effect?
9. How do the authors explain the weight loss that occurred in each of the groups?
10. What do the authors conclude about the effectiveness of subliminal audiotapes?
1.In the given research, Merikle and Skanes (1992) tried to evaluate the effectiveness of subliminal self help audiotapes that aimed to help in weight loss to understand whether their effectiveness was because of a placebo effect. The hypothesis being tested in this study was whether these tapes were really effective to help individuals lose weight or if the reported efficacy of these tapes were merely due to a placebo effect, caused by a belief that subliminal message can be used to cause behavioral change. The study moreover aims to ascertain or debunk the claims of the manufacturers of the subliminal tapes.
2. The researchers divided the subjects (comprised of individuals who wanted to lose weight) in three groups:
- i) Subliminal: This group (comprising of 15 subjects) were given an audiotape containing subliminal messages. The manufacturer of these tapes claimed that the tapes help to lose weight. The tapes were given to the subjects exactly as it was purchased from the distributor Adventures in Learning Inc.
- ii) Placebo: This group (also comprising of 15 subjects) were given audiotapes that were identical in appearance with the tapes given to Group 1 (subliminal). However, each of these tapes were modified in order to replace the original recordings of the subliminal message with different subliminal message that the distributors claimed to relieve dental anxiety and the background music were kept identical to the tapes for weight loss (Phelps & Exum, 2016).
iii) Waiting List: This group (comprising of 17 subjects) were the control group who were not given any tapes. This group was informed that they were in the waiting list, as the maximum number of subjects was already participating in the study, due to which they were placed in waiting list (Karam et al., 2017).
Dividing the subjects in three groups was necessary because it helped the researcher to compare the outcomes from each of these groups and interpret the result without any ambiguity. The first group was given the audiotapes exactly as it was purchased from the distributor, thereby studying the actual effect of the tapes, the second group on the other hand was the placebo group, which helped to identify whether the proposed effects of the audiotapes was because of a placebo effect (as the subjects believed that behavior can be modified using these tapes), while the third group (the waiting list) provided the baseline data, to which the results of the other two groups can be compared, and thus understand whether any observed change in the weight of the subjects was a result of listening to the subliminal messages on the tapes or due to a placebo effect (Foroughi et al., 2016).
1. What question or hypothesis was being tested in this research?
4. In this study, the independent variable is the amount of time listening to the audiotapes, and the type of audiotape given to the subjects (that is whether the tape contains the real subliminal message or a placebo one). This is because both the time each subject listening to the audiotapes could vary with each subject and each subject were placed randomly (as a part of double blind trial) within the three groups. The dependant variable was any observed change in the weight of the subjects, since the change was expected to be caused due to listening to the tapes (Merikle & Skanes, 1992)
5. In this research, the all the tapes were kept identical, and randomly selected numbers were used for their identification. The experimenter was also completely unaware of which tape contained subliminal message and which ones had placebo message, and the tapes were given to the subjects based on a predetermined list. Moreover, none of the subjects were informed about the placebo tapes until the end of the experiment, since they all believed in the efficacy of subliminal messages, and the subjects were never told which tape (subliminal or placebo) they actually received. Thus, both the researcher and the subjects were completely unaware of which tape was shared with which subject, and the presence of the subliminal and placebo was solely on the merit of the tapes given to them, thus making the study a double blind experiment (Nuijten et al., 2016; Violi et al., 2017).
6. The reason for including questionnaires to determine the age and weekly exercise, tobacco use and use of oral contraceptives (filled out by subjects both before and after the experiment) was to understand whether any of these factors were related to any change in the weight of the subjects. This is based on studies that show these factors (age, weekly exercise, tobacco use and use of oral contraceptives) can cause changes in weight (Merikle & Skanes, 1992; Greenway, 2015; Gallo et al., 2016; Bush et al., 2016; Swift et al., 2014).
7. The graph titled Figure 1, compares the changes in weight (which is the average weight across week 1 to week 5) observed in each group (subliminal, placebo and waiting list) to the baseline data (that was collected at the starting of the experiment). The graph thus helps to understand whether there was any observable difference in the average weights of the subjects (from week 1 to 5) after listening to the audiotapes. The graph shows a reduction in the average weight of the individuals in all the three groups compared to baseline, thereby revealing that the three groups did not differ much in the amount of weight lost. The graph suggests that all the three groups lost approximately an equivalent amount of weight in the study, and did not suggest any difference in the weight lost in each group, suggesting very similar outcomes (Merikle & Skanes, 1992).
2. Describe the three conditions (groups) to which different subjects were exposed.
8. Placebo effect can be understood as a beneficial effect that is produced by a placebo and cannot be attributed to actual effect of the placebo but instead is caused by a belief on the placebo itself. This can also be understood as the ‘power of suggestion’ where a positive effect can be caused just by suggesting the efficacy of a treatment. For example, homeopathy has been considered as a placebo medicine in many studies (Hall et al., 2015).
In the study, the authors pointed out that the changes in the weight across the three groups did not provide any evidence that they were caused by a placebo effect, but instead by a non specific placebo, caused by the belief in the efficacy of subliminal messages by the subjects (Merikle & Skanes, 1992; Linde et al., 2014).
9. According to the authors, the weight loss experienced by the subjects cannot be attributed to a placebo effect, since that would have caused a greater change in weight in the placebo group compared to the waiting list group. The authors also suggested that the weight loss observed in all three groups could be due to an increase in consciousness about their own weights by participating in the study, which can explain the near equivalent weight loss seen in all three groups (Merikle & Skanes, 1992; Alegría & Larsen, 2015).
10. From the study, the authors concluded that subliminal tapes cannot cause any significant changes in behavior through subliminal perceptions, however can still have possible placebo effects, as many individuals strongly believe in their efficacy, and thus can still be useful for them (Merikle & Skanes, 1992).
References:
Alegría, C. A., & Larsen, B. (2015). “That’s who I am: A fat person in a thin body”: Weight loss, negative self?evaluation, and mitigating strategies following weight loss surgery. Journal of the American Association of Nurse Practitioners, 27(3), 137-144.
Bush, T., Lovejoy, J. C., Deprey, M., & Carpenter, K. M. (2016). The effect of tobacco cessation on weight gain, obesity, and diabetes risk. Obesity, 24(9), 1834-1841.
Foroughi, C. K., Monfort, S. S., Paczynski, M., McKnight, P. E., & Greenwood, P. M. (2016). Placebo effects in cognitive training. Proceedings of the national Academy of Sciences, 201601243.
Gallo, M. F., Legardy-Williams, J., Hylton-Kong, T., Rattray, C., Kourtis, A. P., Jamieson, D. J., & Steiner, M. J. (2016). Association of progestin contraceptive implant and weight gain. Obstetrics & Gynecology, 127(3), 573-576.
Greenway, F. L. (2015). Physiological adaptations to weight loss and factors favouring weight regain. International journal of obesity, 39(8), 1188.
Hall, K. T., Loscalzo, J., & Kaptchuk, T. J. (2015). Genetics and the placebo effect: the placebome. Trends in molecular medicine, 21(5), 285-294.
Karam, R., Haidar, M. A., Khawaja, A., & Al Laziki, G. (2017). Effectiveness of Subliminal Messages and Their Influence on People’s Choices. European Scientific Journal, ESJ, 13(17).
Linde, K., Friedrichs, C., Alscher, A., Wagenpfeil, S., Meissner, K., & Schneider, A. (2014). The use of placebo and non-specific therapies and their relation to basic professional attitudes and the use of complementary therapies among German physicians–A cross-sectional survey. PloS one, 9(4), e92938.
Merikle, P. M., & Skanes, H. E. (1992). Subliminal self-help audiotapes: A search for placebo effects. Journal of Applied Psychology, 77(5), 772.
Nuijten, M., Blanken, P., van de Wetering, B., Nuijen, B., van den Brink, W., & Hendriks, V. M. (2016). Sustained-release dexamfetamine in the treatment of chronic cocaine-dependent patients on heroin-assisted treatment: a randomised, double-blind, placebo-controlled trial. The Lancet, 387(10034), 2226-2234.
Phelps, B. J., & Exum, M. E. (2016). Subliminal tapes: How to get the message across. Skeptical Inquirer.
Swift, D. L., Johannsen, N. M., Lavie, C. J., Earnest, C. P., & Church, T. S. (2014). The role of exercise and physical activity in weight loss and maintenance. Progress in cardiovascular diseases, 56(4), 441-447.
Violi, F., Targher, G., Vestri, A., Carnevale, R., Averna, M., Farcomeni, A., … & Pastori, D. (2017). Effect of aspirin on renal disease progression in patients with type 2 diabetes: A multicenter, double-blind, placebo-controlled, randomized trial. The renaL disEase progression by aspirin in diabetic pAtients (LEDA) trial. Rationale and study design. American heart journal, 189, 120-127.
Order an Essay Now & Get These Features For Free:
Turnitin Report
Formatting
Title Page
Citation
Outline
