[About placebos and nocebos: healing through words]

Area of Science:

• Neuroscience
• Psychology
• Pharmacology

Context:

• The placebo effect, yielding pain relief from inert substances, is well-researched.
• The nocebo effect demonstrates how negative expectations can induce or worsen symptoms, particularly pain.
• Understanding these opposing phenomena is crucial for pain management.

Purpose:

• To explore the neurochemical underpinnings of the placebo and nocebo effects.
• To elucidate the distinct neuronal systems involved in pain expectation.
• To highlight the link between psychosocial factors and pharmacological outcomes in pain.

Summary:

• Placebo analgesia is mediated by endogenous opioids.
• The nocebo effect, involving pain increase, is linked to cholecystokinin.
• These findings suggest opposing neurochemical systems govern pain expectations.

Impact:

• This research bridges psychosocial influences and pharmacological effects in pain management.
• It offers insights into the therapeutic potential of verbal suggestions and expectations.
• Understanding these mechanisms can refine pain treatment strategies.