Motivation and emotion/Book/2023/Placebo effect and motivation

Placebo effect and motivation:
What is the placebo effect and how can it affect motivation?

Multimedia presentation (3 min)

Overview

Figure 1. Cebocap sugar pills: Commonly used in clinical trials to test the placebo effect. Case study: Imagine a young athlete, Alex, who's been struggling with performance anxiety. On the day of a significant race, a coach hands Alex a water bottle, claiming it contains a special drink that boosts performance. Alex drinks it, feeling an immediate surge of confidence and energy. After the race, the coach reveals that it was just plain water. The belief in the drink's power, combined with Alex's intrinsic motivation, led to a personal best time. This scenario portrays the relationship between the placebo effect and motivation.

The placebo effect is a phenomenon where the belief in a treatment leads to real health outcomes (Benedetti, 2014). It is a topic of long-standing interest in scientific and clinical communities. Yet what makes the placebo effect so compelling? And why does it warrant attention? The significance of this phenomenon extends far beyond its immediate effects; it challenges our conventional understanding of treatment efficacy and highlights the profound psychological influences on health.

Recent research has illuminated the different types of placebo responses, each driven by distinct physiological and psychological mechanisms. Our inner drives, desires, and motivations play a pivotal role in amplifying the effects of a placebo. Various theoretical perspectives shed light on this connection. Moreover, understanding the placebo effect can have significant implications for real-world applications, such as medical treatments, patient care, and our understanding of human motivation.

This chapter delves into the interplay between the placebo effect and motivation, and explores how our beliefs can shape our behaviours and outcomes. By understanding this relationship, we can utilise the power of belief to drive positive change in our various aspects of our lives.

Focus questions: What is the placebo effect? How do our beliefs and motivations influence the efficacy of a placebo? How can the placebo effect shape our motivations and drive our actions? What are the real-world applications of harnessing the placebo effect?

Understanding the placebo effect

Definition

The placebo effect refers to the therapeutic and beneficial outcomes that arise from a treatment that has no therapeutic activity, driven primarily by the patient's belief in the treatment's efficacy (Benedetti, 2014). Placebos can be any treatment, procedure, or ritual that doesn't have a direct therapeutic action but still produces an actual or perceived benefit (Kaptchuk, 2002).

Actual effects and perceived effects

Actual effects refer to tangible and measurable outcomes, such as reduced inflammation or lowered blood pressure, which indicate a direct physiological change (Benedetti et al., 2014) and can be objectively verified (Hróbjartsson & Gøtzsche, 2001). On the other hand, perceived effects are subjective improvements reported by patients, like feeling less pain or experiencing improved mood, which might not always align with objective measures (Price et al., 2008). These may be influenced by various factors, including expectation, conditioning, and psychological state.

Types of placebos

Recent research has identified types of placebo responses (see table 1), each driven by distinct mechanisms depending on the specific context in which the placebo is administered.

Table 1. The different types of placebos

Type of Placebo	Description	Examples
Inert Placebos	These are substances that have no therapeutic effect on the condition being treated.	Sugar pills e.g. cebocap (see figure 1), saline injections
Active Placebos	These are substances that do not treat the target condition but produce side effects similar to the active drug, making them useful in double-blind trials.	Atropine (can mimic side effects of some drugs without the therapeutic effect)
Physical Placebos	Physical interventions that mimic active treatments but are inactive in themselves.	Sham surgeries, acupuncture with retractable needles
Psychological Placebos	Interventions or therapies that mimic actual psychological treatments but are inactive.	Non-therapeutic counseling sessions, relaxation tapes without therapeutic content
Device Placebos	Devices that appear to deliver therapeutic interventions but are inactive.	Sham Transcranial Magnetic Stimulation (TMS), non-functional ultrasound machines

Historical context

The placebo effect has undergone significant shifts in understanding over time. Originally, the term "placebo" derived from the Latin phrase meaning "I shall please," reflecting early observations by medical practitioners who noted patient improvements after receiving treatments devoid of any known therapeutic value. For centuries, the concept was often viewed as a treatment administered primarily to appease or fulfil a patient's needs or desires, inherently carrying a motivational component. However, in more recent times, this understanding has evolved. The modern conceptualisation of the placebo effect has transitioned from merely focusing on the inert components of a placebo to emphasising the entire therapeutic experience it simulates. Despite recent significance in clinical trials, as highlighted by Beecher's 1955 paper (Beecher, 1955), and progress in foundational studies by Ader (1997), Amanzio & Benedetti (1999), and Kirsch (1997), the relationship between motivation and the placebo effect remains under-researched, leaving much to be uncovered.

Underlying Mechanisms

Research examining the placebo effect has been underpinned by various physiological and psychological processes.

Psychological Processes:

Classical conditioning

From a classical conditioning perspective, the placebo effect can be understood as a learned response. Classical conditioning, developed by Ivan Pavlov (1927), involves pairing a neutral stimulus with an unconditioned stimulus that naturally produces an unconditioned response. Over time, the neutral stimulus alone can elicit the same response (conditioned response) (see Figure 2).

In the context of the placebo effect, a placebo (an inert substance or procedure) can be seen as the neutral stimulus. When it's repeatedly paired with an active treatment (the unconditioned stimulus) that produces a therapeutic effect, the body learns to associate the placebo with the therapeutic outcome. As a result, even in the absence of the active treatment, the placebo can elicit a therapeutic response akin to the genuine treatment, making this the conditioned response (Wickramasekera, 1985).

This association is supported by studies that have demonstrated conditioned responses as pivotal mechanisms underpinning the effects of placebos, with evidence found in both human and nonhuman animals (Flaten & Blumenthal, 1999; Hernstein, 1962). For instance, if an individual has previously experienced genuine relief from a treatment, they might anticipate and experience similar relief from a placebo, associating the treatment process with the relief (Amanzio & Benedetti, 1999).

Expectation

Another one of the primary factors of the placebo effect is expectation. Expectation is a belief about the potential outcomes associated with a future event or situation (Olson et al., 1979)

The expectancy perspective posits that the placebo effect is primarily driven by this expectation that a treatment will yield a specific outcome (Kirsch, 1999). When individuals anticipate a positive outcome from a treatment, their belief can lead to automatic subjective or physiological reaction (response expectancy). Such expectations can be shaped within a specific context in which the treatment is delivered. This context encompasses social and physical cues, verbal suggestions from healthcare professionals, the individual's treatment history, or even the presentation of the treatment itself (e.g., demand characteristics) (Benedetti, 2014) The brain actively interprets this context, eliciting expectations, desires, memories, and emotions. Previous positive or negative experience may also influence the magnitude of placebo (Colloca & Benedetti 2006). These factors taken together, are likely to vary greatly across clinical and research contexts and consequently generate considerable variability in the placebo effect itself.

Expectancy theory

Vroom's expectancy theory (1964) provides a complementary lens to understand this phenomenon. It posits this motivation is a product of three key beliefs: the expectation that effort will lead to performance (expectancy), the belief that performance will result in a specific outcome (instrumentality), and the value they place on that outcome (valence).

In this sense, positive reinforcement, supportive settings, and authoritative figures can contribute to a patients strong belief that a treatment will lead to positive health outcomes, enhancing their perception of its efficacy (Kaptchuk et al., 2008). These response expectancies are also believed to be self-confirming (self-fulfilling prophecy).

However, it is important to note the precise mechanisms through which expectations produce the placebo effect remain a topic of ongoing investigation and debate (Olson et al., 1996).

Physiological Processes:

Research has also revealed tangible neurobiological changes in the brain and body associated with the placebo effect.

Brain imaging and neurochemical mechanisms

Neuroimaging techniques, such as fMRI, have illuminated alterations in brain activity associated with the placebo effect. Specifically, regions involved in anxiety, pain perception, emotional regulation, reward processing, and expectancy formation can be influenced by placebo administration (Wager et al., 2004). For instance, the orbitofrontal cortex (OFC) and dorsolateral prefrontal cortex (DLPFC) play roles in cognitive control and affective responses to pain anticipation (Wager et al., 2004). Other areas of activation include the anterior cingulate, nucleus accumbens, amygdala, and the spinal cord. Furthermore, the release of neurochemicals such as neuropeptides (endogenous opioid) (Benedetti et al. 1999) and endorphins (Levine et al., 1978) have been identified.

Other physiological systems

Beyond the brain, the placebo effect has implications for the other physiological systems. For example, beliefs and expectations about a treatment can modulate immune responses (Hadamitzky et al., 2018). Classical conditioning mechanisms can also induce physiological responses similar to the drug itself (Ader & Cohen, 1982).

The interplay: Placebo and motivation

Building upon the above psychological and physiological mechanisms, the motivational perspective offers an alternative nuanced understanding of the placebo effect. It emphasises the intertwined roles of motivational beliefs, expectations, and non-conscious goals (such as desire) in shaping individual responses to treatments.

Motivational explanations have posited that the placebo effect emerges from one's innate desire to feel better or experience reduced anxiety (Ceci et al., 1985). Some scholars have suggested that motives centred on self-enhancement can modify placebo responses (Gibbons & Gaeddert, 1984).

Similar to the expectancy perspective, recent research underscores the role of non-conscious goals in shaping behavior and cognition. These goals are activated by situational cues which guide attention, behavior, and cognition without the individual's conscious awareness (Chartrand & Bargh, 1996). For instance, in a medical setting, the mere presence of physicians or medical devices might non consciously activate a goal to cooperate, subsequently altering an individual's thoughts and behaviours (Moskowitz, 2002).

Self-determination theory

Self-determination theory (Deci & Ryan, 1985) posits that individuals have innate psychological needs for competence, autonomy, and relatedness. Belief serves as a foundational pillar, setting the stage for goal pursuit, while expectations dictate the direction and intensity of efforts. When these needs are satisfied, individuals experience optimal growth, well-being, and motivation.

In the context of the placebo effect, if a patient believes that a placebo treatment aligns with their values and satisfies their need for competence in managing their health, they may be more intrinsically motivated to adhere to the treatment and perceive positive outcomes. Conversely, if the treatment is perceived as externally imposed without addressing the individual's core needs, its efficacy might be diminished.

Self-efficacy theory

The concept of self-efficacy, or the belief in one's capability to succeed, further underscores the intricate relationship between belief, expectation, and motivation (Bandura, 1977). According to this theory, individuals with high self-efficacy are more likely to take on challenging tasks, persist in the face of obstacles, and recover more quickly from setbacks. This interplay creates a feedback loop: successes bolster belief, which in turn reinforces motivation, setting the stage for a cycle of continued achievement and enhanced motivation over time (Dweck, 2000; Locke & Latham, 1990).

In this sense, a patient believes in their own capability to heal or improve, and they are given a placebo treatment, their inherent self-efficacy can amplify the perceived effectiveness of that placebo. A strong belief can amplify confidence, leading to heightened effort and perseverance (Bandura, 1977), while doubts or negative beliefs can stifle progress (Dweck, 2000).

Quiz Time! How does belief in a placebo potentially boost motivation? By increasing levels of dopamine in the brain. Through the power of positive thinking and expectation. By altering the physical condition directly. By reducing the need for actual medical treatments.

Real-world implications and applications

In clinical and therapeutic settings

Placebo controls are essential for rigorous investigations of new treatments and therapies (i.e., the double-blind, randomised, placebo-controlled clinical trials) (Geers, 2005). The placebo effect has been observed virtually all areas of patient care across various medical conditions and therapeutic interventions in clinical settings. In pain management, studies have shown that placebo treatments can lead to significant reductions in pain levels (placebo analgesia) (Pollo et al. 2001). The placebo effect has also been observed in the treatment of depressive disorders. A meta-analysis of antidepressant drug trials found that while active drugs were effective, a significant portion of the therapeutic response was duplicated in placebo control groups (Kirsch et al., 2008). Some studies notably indicate that the impact of most antidepressant medications is almost entirely due to the placebo effect (e.g., Kirsch & Sapirstein, 1998). In parkinson's disease, placebo treatments may lead to the release of dopamine in the brain, mirroring the effects of active dopaminergic drugs (de la Fuente-Fernández et al., 2001).

In individual settings

The potential of placebo effects can extend beyond clinical treatment interventions to include individuals’ internal attempts to influence their conditions.

In sports performance, athletes' confidence in their training and inherent abilities often can propel them to outperform competitors filled with doubt (Jones & Harwood, 2008). Similarly, in the academic arena, students who possess a strong belief in their intelligence and capabilities tend to not only achieve higher grades but also develop a growth mindset, leading to long-term academic excellence (Dweck, 2006). Relationships, both platonic and romantic, thrive when there's a foundational belief in mutual trust, understanding, and commitment, which fosters stronger bonds and healthier interactions (Arriaga et al., 2014). In the professional world, work productivity is enhanced when employees believe in their skills and the intrinsic value of their work, leading to increased engagement and job satisfaction (Luthans & Youssef-Morgan, 2017). Furthermore, in the sphere of health and wellness, individuals who internalise the benefits of a healthy lifestyle, driven by belief, tend to make proactive choices that promote well-being (Prochaska & Velicer, 1997).

Strategies to harness the placebo effect

There are strategies to leverage the placebo effect which are deeply rooted in psychological principles and can be applied in clinical/ therapeutic or individual contexts to enhance motivation and drive positive outcomes.

Positive reinforcement: Positive feedback about the efficacy of a treatment can enhance an individual's belief in its effectiveness, thereby amplifying the placebo response (Benedetti, 2014). For instance, a doctor's affirmation about the potential benefits of a placebo treatment can bolster a patient's confidence in its therapeutic value.

Setting expectations: Placebo-induced expectancies can be harnessed to improve individuals’ internal attempts to regulate their emotions. For instance, distraction in the face of unpleasant emotions (e.g., fear) can be used to improve the effectiveness of emotional regulation (Shafir et al., 2023).

Ritualistic behaviours: Rituals can enhance the perceived efficacy of a treatment. The act of taking a pill, even if it's a placebo, can in itself trigger therapeutic responses due to the ritualistic nature of the act. Rituals provide a sense of familiarity and control, which can reduce anxiety and enhance the perception of treatment efficacy (Beecher, 1955). Incorporating rituals into treatment protocols may involve specific ways of administering medication or engaging in preparatory behaviours.

Figure 3. Storytelling: A powerful tool in shaping beliefs and enhancing the placebo effect.

Storytelling: Sharing success stories of individuals who have benefited from similar treatments can bolster belief in the efficacy of a placebo intervention (see figure 3) (Price et al., 2008). Narratives can shape beliefs and expectations, and tap into our innate human tendency to relate to and be influenced by personal narratives. Humans are inherently drawn to stories, and when we hear of others' positive experiences, it reinforces our own beliefs and expectations about the treatment.

Challenges and criticisms

While the placebo effect is often associated with positive outcomes, it's important to note that this phenomenon is not always beneficial. There are ethical and practical implications of using placebos in practice.

Ethical considerations

Giving placebos without participant consent raises ethical issues about autonomy and deception (Colloca & Miller, 2009). Patients may mistakenly view placebos as proven treatments, fostering false hope (Lidz et al., 2004). There's a risk that the placebo effect might be used to justify ineffective treatments or interventions, especially in alternative medicine (Ernst & Resch, 1995). Moreover, the nocebo effect may arise, when negative expectations or beliefs about a treatment lead to detrimental outcomes or the exacerbation of symptoms (i.e., they promote pain, distress and disease). For instance, if a patient is informed of potential side effects of a medication, even if the medication is inert, they might experience those side effects purely based on their negative expectations (Häuser et al., 2012).

Limitations

Over-reliance on placebos could downplay or delay better treatments (Colloca & Miller, 2011) and incur unnecessary costs. The long-term consequences of repeated placebo use are unclear, and findings from placebo-controlled trials might not always translate to real-world clinical scenarios (Rothman & Michels, 1994). The placebo effect varies among individuals, influenced by personal, cultural, and situational factors (Benedetti, 2014). Its effectiveness may also be shaped by cultural and societal norms, limiting its generalisability (Moerman & Jonas, 2002).

Conclusion

The relationship between the placebo effect and motivation has been a focal point of this chapter, revealing the profound ways in which our beliefs and expectations can shape our physiological and psychological experiences. As evidenced by various theoretical perspectives, motivation, when driven by strong belief and expectations, can significantly enhance the placebo effect. This combination underscores the broader implications of belief in various domains of our lives, including our personal relationships, professional endeavours, performance domains and overall wellbeing.

While research has made significant developments in understanding the placebo effect and its ties to motivation, it is not without limitations, necessitating cautious interpretation and application of findings. Future research should prioritise a comprehensive understanding of its implications, considering both positive and negative aspects across individuals and cultures. Ethical considerations must be at the forefront, ensuring informed patient consent and avoiding endorsement of unproven therapies.

Nevertheless, by understanding and harnessing the power of the placebo effect and motivation, we can open up possibilities for enhancing our well-being and achievements in various facets of life.

See also

• Placebo (Wikipedia)
• Placebo effect (Wikipedia)
• Healing and emotions (Book chapter, 2014)
• Placebo analgesia (Wikipedia)
• Nocebo effect (Wikipedia)

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External links

• The power of the placebo effect (Harvard Health)
• Harnessing the power of placebo (TEDMED Youtube)
• The powerful placebo (Beecher's 1955 paper, DC Science)