Psychology Journal Critique Paper Example

Psychology Journal Critique Paper Example

Hopker, Foad, Beedie, Coleman, & Leech (2010) performed a study to determine how conditioned stimuli affect subsequent response to unconditioned stimuli. They used a placebo to act as conditioned analgesia to show how it affected subsequent analgesic response, which they coupled with an individual’s expectations of outcome of the interventions; positive outcome is expected if a person holds positive beliefs and vice versa (Hopker, Foad, Beedie, Coleman, & Leach, 2010).

 

The researchers applied their theory in sports medicine to show how a placebo analgesic affected the pain endurance after an injury. Previous studies have demonstrated that a person’s expectation of relief from pain has the ability to modify how effective an administered substance is, whether it is an inactive placebo or an active analgesic. Persons informed about placebo as inactive experience no pain relief even if they had demonstrated decreased pain on previous trials when they had no knowledge about the placebo deception.

 
Hopker et al wanted to find out if there is relationship between the outcomes of therapy in sports environment and an individual’s expectation; they used a placebo muscle gel to treat muscle pain that they induced experimentally. They hypothesized that if they linked application of the gel with the expectation of reducing pain, they would require a higher level of pain stimuli to elicit a certain pain response in placebos than that in controls.

Hopker et al had to adhere to ethical standards of deception in research because use of a placebo involves deception about the therapeutic effects of a substance; otherwise, the expected outcome is not achievable. They would inform the participants about it after they collected all data and would perform a medical exam to rule out any condition that would interfere with the outcome.

 
They chose twenty-four people, eight female and sixteen males who were in the university between the ages of 16 to 25. Pain induced artificially in the range used during electrotherapy, one pole on superior part of gastrocnemius and the other on inferior part, and the frequency set high to avoid involuntary contraction of muscles and increased gradually to make it easy to assess the level of stimulation. They did the experiments five times over five weeks using the same leg with the other as control then reversed later on. The level of stimulation required to elicit a 6 to 10 pain level on visual analog scale was the dependent variable.

The researchers informed the participants that the first test was to identify adverse effects in the procedure but the true aim was linking the inert gel that was the unconditioned stimulus, to pain reduction, the conditioned response. They first determined the perceived pain rating of 6/10 by the participants then application of a placebo made of ultrasound transmission gel with added camphor oil for olfactory stimulation and informed the participants it was an analgesic used by professional sportsmen and reduced muscle pain.

After that, the pain stimulation introduced again but decreased by 20% though the participants informed it was the same level as before in order to create a false impression of reduced pain because of the placebo. The level of stimulation for a pain scale of 6/10 was set in the baseline trials. In subsequent tests, the participants allowed to set the level of stimulation that elicited pain scale of 6/10 to provide a baseline then the placebo applied and the procedure repeated on the experimental and control legs, different from those used during the first trial; they then repeated baseline after intervention.

There was significant effect obtained after placebo gel application as opposed to control conditions; after placebo application, the pain threshold rose by 8.2%. Difference also seen with the same leg first used as control then as placebo leg, significant difference between the changes in pain threshold at post baseline when compared with placebo condition but no difference noted in the baseline and control.

The results were consistent with the hypothesis of the researchers because they demonstrated that using a placebo subsequently reduced the pain experienced in placebo leg as opposed to control and giving the participants positive expectations that the placebo had been effective before among professional sportsmen increased its therapeutic effects. The results also showed that the effects of the placebo are specific and not generalized because effect was seen in placebo leg only and not the control. The method they used of starting first with the placebo leg then the control was appropriate as it helped compare the two and note any difference in the level of stimulation required in both legs.

However, it would have been good to know if the placebo could act alone without giving positive expectations to be sure that the placebo acted as true conditioned stimuli as opposed to the effects resulting from expectancy alone, this is because the participants’ knowledge about the expected effects affected the magnitude of the placebo response. One way of doing it would be introducing negative beliefs in one group of the participants and positive beliefs in another.

Another approach would be giving an active substance in one group and a placebo in the other and use real injured sportsmen as opposed to introducing the pain experimentally so that the results would have more ecological value. This would have allowed determination of whether the active agent and the placebo achieved the same level of pain threshold.
The study successfully proved non-therapeutic substance conditioned to achieve effects similar to those of the real substance is possible (Hopker, Foad, Beedie, Coleman, & Leach, 2010).

Reference
Hopker, J. G., Foad, A. J., Beedie, C. J., Coleman, D. A., & Leach, G. (2010). Placebo effect of an inert gel on experimentally. Open Access Journal of Sports Medicine, 215-220.