Healthy
Conditions
Keywords
nonverbal vocal communication, pain tolerance, cold pressor test, Nociception Level Index, Video pupillometry
Brief summary
Humans produce non-verbal vocalizations (shouting, growling, screaming), laughter, ...) in various contexts that are likely to perform biological functions. and important social issues. Yet despite their importance in the human vocal repertoire, the mechanisms and functions of non-verbal vocalizations remain little studied and poorly understood including in humans. In this context, the investigators wish to examine how the production of vocalizations non-verbal communication influences pain tolerance in healthy adults.
Detailed description
Humans produce nonverbal vocalisations such as screams, grunts, roars, cries and laughter across a variety of contexts. Yet despite the prominence and apparent importance of these nonverbal sounds in human communication, the investigators still know very little about their influence on human perception and behaviour. That's why, in this study, the investigators will examine specifically the influence of nonverbal vocal production on pain tolerance. The remainder of the study will involve up to three trials of a pain tolerance (cold pressor) task, during which the investigators will ask participants to produce vocalisations (e.g., screams or words) while submerging the participant's hand in bath of circulating cold water. The results of the study will contribute to our theoretical understanding of the functions of nonverbal vocal communication in humans, in particular the influence of nonverbal vocal production (i.e., yelling) on pain tolerance.
Interventions
The cold pressor test is among the most common and established methods for studying human reactions to pain and pain tolerance. Participants submerge a hand in cold water (approx. 5°C) and are asked to keep their hand submerged for as long as can (until the sensation is intolerable), up to a maximum of 5 min. The procedure is safe because the hand is removed before adverse effects can occur. The participant will be given a break of 5 min in between trials, and will interchange hands between trials. During this break hand may to be place in warm water (25-35°C) for up to 4 min to normalise hand temperature, which will be measured before and after each trial using a digital thermometer held firmly in the palm of the hand. Each participant will complete no more than three trials (conditions) in a randomised order.
During the experiment, the vocalizations produced will be systematically recorded for each participant and an analysis of the acoustic structure of these vocalizations will be carried out.
Four sensors placed non-invasively on one finger. of the participants will be able to calculate a dozen physiological parameters converts in real time into a pain index called NOL (for Nociception Level Index).
This technique is based on the observation of the dilatation of the pupil during the perception of a nociceptive stimulus in test persons.
Sponsors
Study design
Eligibility
Inclusion criteria
* Participant in good health * Affiliated or entitled participant in a social security scheme * Participant who has received informed information about the study and has co-signed a consent to participate in the study with the investigator.
Exclusion criteria
* Chronic pain * High blood pressure or poor circulation * Cardiac or vascular disease, or a heart condition (including symptoms of Raynaud's syndrome) * Allergy or hypersensitivity to cold * Diabetes * Epilepsy * Pregnancy * Recent serious injury * Neurological or psychiatric condition known to affect pain tolerance (e.g., peripheral neuropathy, schizophrenia) * History of fainting or seizures * History of frostbite * Chronic smoker (more than 10 cigarettes a day)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pain tolerance | at inclusion | Delay (in seconds) in removing the hand when testing the Cold Pressor. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Onset of pain | at inclusion | Participant verbally indicates when he or she begins to feel the sensation of pain (time of onset measured in seconds) |
| Pain intensity | at inclusion | Subjective assessment of maximum pain intensity by participants for a given trial. Measured by scale of 0 (no pain) at 100 (extreme pain). |
| correlation between NOL index and pupillary diameter | at inclusion | Measurement of the NOL index (index ranging from 0 to 100) and measurement of pupillary diameter (in mm) and its variations in response to nociceptive stimuli by video pupillometry. |
| Analysis of Acoustic Recordings | at inclusion | Using a dedicated script in software specialised in acoustic analysis (e.g. PRAAT). |
Countries
France
Contacts
Centre Hospitalier Universitaire de Saint Etienne