Somatotopic organization of brainstem analgesic circuitry

Rationale: By conducting a placebo analgesia conditioning paradigm using a falsely labelled and described cream, 93 pain-free participants believed this cream could reduce the intensity of painful heat applied to either their face, arm, or leg. In reality, this “lidocaine” cream was a placebo, and the temperature of a thermode surreptitiously lowered whenever placed onto this cream relative to a control Vaseline cream site. During collection of images of brainstem activity using a 7-Tesla Magnetic Resonance Imaging scanner, both the placebo and control cream sites received identical temperatures, with a decrease in perceived pain intensity during the placebo cream site stimulation being a placebo analgesia response. We analysed activity changes in the PAG and an area that the PAG contacts to inhibit pain, the rostral ventromedial medulla (RVM), during analgesia responses on the face, arm, and leg. Further, using the hidden application of a third cream to a separate body site, we explore..., , # Somatotopic organization of brainstem analgesic circuitry

Dataset DOI: [10.5061/dryad.np5hqc064](10.5061/dryad.np5hqc064)

These data accompany the submission \"Somatotopic Organization of Brainstem Analgesic Circuitry\" - including behavioural pain and expectancy ratings, and raw 7-Tesla brain imaging datasets for conditioned placebo analgesia evoked on the face, arm, or leg. This readme file explains the content of each folder, and any further questions regarding the data can be sent directly to the first or corresponding author. 

## Description of the data and file structure

Human 7-Tesla functional MRI data of conditioned placebo analgesia evoked on the face, arm, or leg. 

Accompanying Excel provides average pain intensity data during each fMRI sequence, as well as demographic data including age and sex. 

Functional sequences consisted of a block design with 134 dynamic scans included in each 4D nifti file for responder and nonresponder groups of each skin site. Each sequence c..., Consent was attained for future use of de-identified functional imaging data, in this instance uploaded to the public domain.
Image de-identification was performed through DICOM to Nifti conversion, stripping the header information from individual participant data.
Participants have been coded as \"participant 1, 2, ...\" in both nifti imaging and behavioural datasets.