Placebos and Nocebos With and Without Deception and their Effect on Cognitive Performance
NAME
University of Sydney

Abstract
Past research has produced conflicting conclusions about the effectiveness placebos with and without deception. It has been argued that, although placebos sometimes appear to be more effective with deceptive administration, it is not an ethical way to carry out research or provide treatment. This study aimed to determine whether a significant placebo effect could be achieved through deceptive as well as open administration. Cognitive performance was measured and results were collected for both positive and negative outcomes. The 512 participants were given different instructions and suggestions about the placebo (or nocebo) and then asked to sniff an odour while completing a visual search task. Results indicated that both placebos and nocebos require deception to have a significant effect. Groups with open administration did not show significant effects. It was also shown that odour did not have an effect on performance. Further research is needed to investigate different ways to introduce a placebo to patients, for example, alternative wording in instructions and suggestions.

Placebos and Nocebos With and Without Deception and their Effect on Cognitive Performance Many researchers have been interested in determining the most effective and ethical way to administer a placebo. The placebo effect can be defined as a change in physical or mental wellbeing resulting from the symbolic influence of treatment or the treatment environment (Broody, 2000). A particular point of interest is whether a placebo is still effective if it is ethically administered without deception or concealment. The ethical implications surrounding the use of placebos are complex. To administer a placebo with deception is to mislead a patient and undermine trust. An article has stressed the importance of ethics in medical treatment and in particular, the use of placebos in research (Temple & Ellenberg, 2000). Temple and Ellenberg (2000) assert the need to gain informed consent from patients agreeing that they will use a placebo treatment. They assert that patients should be informed of any existing effective treatment, and acknowledge the risk that the placebo may be ineffective, or even damaging. Therefore, it is important that further research is conducted, in order to determine the possibility that placebos may still be effective without the use of deception or concealment. Dahan et al. (1986) found that informed consent prevented the effectiveness of a placebo. In this study, patients suffering with insomnia were assigned to two placebo groups; a control group without informed consent, and a group with informed consent. It was found that the placebo treatment had a significantly greater effect with deception. However, in one study, Kaptchuk, et al (2010) examined the effectiveness of a placebo without deception. Consent was given by patients suffering with IBS to participate in the study which truthfully described pills to be taken as inactive. Furthermore, patients were informed that placebos can have real effects and could help to improve their health. Their findings showed that the open placebo group had significantly better results than the no treatment control group. The implications of this study could mean that medical practitioners can use the positive effects of placebos, with full consent of patients. Similarly, Park & Covi, (1965) found that an open placebo, without deception can be an effective treatment. Anxious neurotic outpatients were given pills which they were accurately told were inert. Their attitudes to the treatment were documented, with some believing that the pills were placebos and others believing that they contained drugs, with different degrees of certainty. As well as finding improvements in the wellbeing of patients, it was also found that there was no apparent relationship between the patients’ belief in the contents of the pill, and improvement of health. This study hopes to contribute to the existing knowledge of placebos by not only comparing results of open and deceptive placebo testing, but also comparing results of open and deceptive nocebos. There are still many questions, particularly concerning ethical approaches, about placebos and especially nocebos that need to be addressed. The present study aims to determine whether placebos require deception, or, if they can be administered openly, with informed consent. It will also suggest whether or not a nocebo requires deception. From the research explored, it was found that there were conflicting results. Since this present study is similar to those already examined, there was no obvious anticipated result about the open placebo or nocebo groups. However, from the results of previous research, it was anticipated that the deceptive placebo and deceptive nocebo would demonstrate improvements and impairments in performance, respectively.
Results
An examination of the data found that between certain groups, there was a statistically significant difference of initial mean scores. The mean scores of reaction time for open and deceptive placebo and nocebo, odour control and no treatment are presented in Table 1. Table 2 presents the statistical results, with an alpha level of 0.05. Results indicate that a placebo administered with deception has a significant effect on increasing cognitive performance compared to odour control, p