Leveraging the Shared Neurobiology of Placebo Effects and Functional Neurological Disorder: A Call for Research, 2019, Burke et al

Andy

Retired committee member
Not a recommendation.
Placebo effects can be defined as positive responses to the therapeutic context surrounding administration of an active or inactive treatment. These effects are believed to be mediated by a variety of overlapping external (e.g., environmental cues and the patient-physician relationship) and internal (e.g., expectancies, emotions, and cognitive framing) factors (1). Much of the attention given to placebo effects in medicine has focused on their role in placebo-controlled clinical trials and the nuisance they can pose on measurements of clinical efficacy. However, a growing body of research is demonstrating that placebo effects, in their own right, can meaningfully modulate brain regions/networks and neurotransmitter systems (1). Thus, there is a strong need to better understand and harness these biologically based changes that now present a new frontier in translational medicine (2).

The majority of studies interrogating placebo effects have focused on healthy volunteers; however, an increasing number of studies are recruiting clinical populations, such as patients with Parkinson’s disease, chronic pain, and other neuropsychiatric disorders (3). Interestingly, the neural mechanisms underlying placebo effects have been found to be the same as or similar to mechanisms targeted by active pharmaceutical interventions for many of these disorders (2, 3). Functional neurological disorder (FND) can be briefly defined as the presence of neurological symptoms that are incompatible with recognized neurological/medical disease and may or may not be associated with psychological stressors (4). These disorders are challenging to manage, have a limited set of treatment options, and pose a large burden on health care system resources (5). Anecdotally, many clinicians have recognized that patients with FND may have very strong placebo responses, and some of these cases have been described in the literature (6). However, to the best of our knowledge, no study to date has directly investigated placebo effects in FND, and data demonstrating placebo responses from FND clinical trials are limited.

In this article, we propose that leveraging placebo effects could be meaningfully incorporated into the management of patients with FND. We build on previous discussions of this topic (6, 7) and offer an argument focusing on the convergent literature revealing the shared neural substrates between the brain’s “placebo network” and the dysfunctional networks implicated in the pathophysiology of FND. Although there are likely many common pathways and nodes of overlap between FND and placebo networks in the brain, we focus on the amygdala for simplicity and clarity. We then conclude by briefly outlining different approaches and strategies for optimizing the translation of placebo effects toward the treatment of FND.
Open access, https://neuro.psychiatryonline.org/doi/10.1176/appi.neuropsych.19030077

ETA: Added "Not a recommendation."
 
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Has it been demonstrated that placebo effects are present in objective outcome measures as well as subjective measures?

Does a placebo involve a real change in an underlying condition, be it biomedical or psychological, or does it just result in the subject just believing things are better?

[Added - I am quite happy for any improvement, regardless of whether it is or is not a placebo, indeed I would be happy for purely subjective improvement even if that was ‘delusional’ if it was possible to sustain that delusion long term. I suspect a number of things I have tried over the years (E.g. food supplements, osteopathy, shiatsu) that seemed to produce short term improvement were a placebo effect. Interestingly with a number of things, such as shiatsu, the apparent improvement only lasted during the intervention or for a period of weeks following it.

However, given the nature of ME, which is worsened by over exertion, any placebo that is purely subjective, that does not change the underlying condition is dangerous. Anything that undermines an individual’s insight into their current thresholds for triggering crashes or their current energy envelope puts them at risk of deterioration, even permanent worsening of their condition.
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Has it been demonstrated that placebo effects are present in objective outcome measures as well as subjective measures?

No objective meaningfully clinical outcomes.

There are transient short term changes in neurotransmitters (which would also occur from many other pleasing activities), as well as increased conditioned induction of the endorphin system in the short, but not medium/long term. Basically, a placebo could be useful for short term benign pain or nausea conditions, but little else.
 
These effects are believed to be mediated by a variety of overlapping external (e.g., environmental cues and the patient-physician relationship) and internal (e.g., expectancies, emotions, and cognitive framing) factors
They do not even talk about regression to the mean, which is a huge factor in what is called the "placebo effect", they've only selected perceptive causes for placebo effect, that tells how biased they are.
 
It seems they've set things up so they cannot fail. They will be able to show modest positive transient effects over a no treatment control on the first try, for any condition, and they will interpret them as evidence of benefit. The transient nature of the effects will be interpreted as evidence that patients need to be treated often. It will be difficult to disprove the claims of treatment efficacy. They will soon learn to avoid the more objective outcomes and focus on the most subjective ones instead. Their peers will not criticize them because the "software error" narrative panders to popular prejudice. The alleged positive effects will appear to justify the popular prejudice.

It could be risky for them to include ME/CFS patients though.

PS: I forgot. Introducing expectation bias will be seen as essential part of treatment, rather than something to avoid.
 
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I mean, it's literally the control for "no effect". Should we upend literally all of clinical medicine by adding, what, a second control for no effect? What would that second "no effect" would be?

In food tasting, it would be the one where nothing was added.

In hearing testing, it would be the silence.

You, of all people, actually deride this effect in people who claim to have EMF sensitivities by insisting that they cannot tell the difference between there being a signal or not. You know, the control for "no effect".

By all means actually do put that to the test with objective measurements. But you will never actually do that, will you? Because objective measurements always come back negative and that makes it hard to maintain that the literal control for "no effect" is actually no effect.

Usually The Simpsons did it but this time it's Futurama:

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They do not even talk about regression to the mean, which is a huge factor in what is called the "placebo effect", they've only selected perceptive causes for placebo effect, that tells how biased they are.
At least they admit it's a belief. We got a self-aware wolf right here, i.e. someone who makes an argument against something but actually uses it in support of one thing, aka as being right for the wrong reasons.

Remarkable that they are OK with beliefs as long as they agree with that, while mocking people for the same thing about beliefs they don't agree with. That's ridiculous inconsistent but, hey, is that really important in science? Yes, yes it truly is.
 
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