Countermeasures to Reduce Sensorimotor Impairment and Space Motion Sickness Resulting From Altered Gravity Levels

Vestibular Clinical Trial

Official title:

Countermeasures to Reduce Sensorimotor Impairment and Space Motion Sickness Resulting From Altered Gravity Levels

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02136420
• Other study ID #: 497997
• Status: Completed
• Phase: Phase 4
• First received: April 30, 2014
• Last updated: December 7, 2017
• Start date: June 2014
• Est. completion date: December 2016

Study information

• Verified date: December 2017
• Source: Massachusetts Eye and Ear Infirmary
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The investigators will study adaptation of motion perception and manual control in altered gravity, including the effects of a drug (promethazine). The investigators will also study whether promethazine affects motion perceptual thresholds.

Description:

Adaptation to altered gravity has been of concern from the earliest reports of space motion sickness, through the Apollo exploration era, and into current planning of exploration missions. The proposed research program takes a new approach which could lead to an effective, practical and acceptable protocol for preadapting astronauts to space flight. By using the gravito-inertial alterations possible with centrifugation in different body orientations the investigators will quantify an individual's sensory adaptation capability and use it to predict and to minimize the consequences of movement in any other gravity environment - eventually including weightlessness. The investigators will also study whether a drug (promethazine) affects motion perception and motion sickness.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: December 2016
• Est. primary completion date: December 2016
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 45 Years

Eligibility

Inclusion Criteria:

• Subjects must be in general good health

Exclusion Criteria:

• Anyone who is not generally in good general health does not qualify

• Cardiovascular disease

• Severe diabetes

• Respiratory condition (e.g. asthma or emphysema)

• Narrow angle glaucoma

• Prostatic hypertrophy

• Gastrointestinal disorders

Related Conditions & MeSH terms

• Motion Sickness
• Vestibular

Intervention

Drug:
• Promethazine
Subject receives promethazine

Behavioral:
• Hyper gravity training
Subject receives hypergravity training before testing

Drug:
• Placebo
Placebo

Behavioral:
• No hypergravity training
Subjects do not receive normal Earth gravity

Locations

Country	Name	City	State
United States	Massachusetts Eye and Ear Infirmary	Boston	Massachusetts

Sponsors (3)

Lead Sponsor	Collaborator
Faisal_Karmali@MEEI.HARVARD.EDU	Massachusetts Institute of Technology, National Space Biomedical Research Institute

Country where clinical trial is conducted

United States, 

References & Publications (1)

Diaz-Artiles A, Priesol AJ, Clark TK, Sherwood DP, Oman CM, Young LR, Karmali F. The Impact of Oral Promethazine on Human Whole-Body Motion Perceptual Thresholds. J Assoc Res Otolaryngol. 2017 Aug;18(4):581-590. doi: 10.1007/s10162-017-0622-z. Epub 2017 A — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Percent Change in Roll Tilt Perception After Exposure to Hypogravity	Note that this applies to arms 1-4 only.; Subjects sat on a chair on a moving platform on top of a centrifuge that created an artificial gravity environment. Subjects were repeatedly roll tilted to angles between 11 and 19 degrees, and then reported their perceived tilt angle using a subjective visual vertical task. They did this while experiencing centripetal acceleration equivalent to Earth gravity (1 Gz), and then hypogravity (0.5 Gz). We hypothesized that, after entering hypogravity, subjects would tend to underestimate their tilt angle. We calculated the percent change in their perception of tilt between 1 Gz and 0.5 Gz.	1 session
Primary	Yaw Perceptual Motion Threshold	This is a perceptual self-motion threshold that measures the precision of the vestibular system. It is analogous to an audiogram, but for motion. Subjects sat on a motorized platform which repeatedly provided them with small motions to the left or right. After each motion subjects report whether they perceived a motion to the left or right. Based on subject responses, a psychometric curve fit is performed that determines the threshold (the standard deviation of the underlying cumulative Gaussian). Yaw rotation means rotations about an axis that is perpendicular to gravity.; This outcome measure applies only to arm 5 subjects.	2 sessions separated by at least four days; measurements made 2 hrs after ingestion of medication
Primary	Roll Perceptual Motion Threshold	This is a perceptual self-motion threshold that measures the precision of the vestibular system. It is analogous to an audiogram, but for motion. Subjects sat on a motorized platform which repeatedly provided them with small motions to the left or right. After each motion subjects report whether they perceived a motion to the left or right. Based on subject responses, a psychometric curve fit is performed that determines the threshold (the standard deviation of the underlying cumulative Gaussian). Roll tilt means rotations about an axis that is Earth-horizontal.; This outcome measure applies only to arm 5 subjects.	2 sessions separated by at least four days; measurements made 2 hrs after ingestion of medication
Primary	Interaural Perceptual Motion Threshold	This is a perceptual self-motion threshold that measures the precision of the vestibular system. It is analogous to an audiogram, but for motion. Subjects sat on a motorized platform which repeatedly provided them with small motions to the left or right. After each motion subjects report whether they perceived a motion to the left or right. Based on subject responses, a psychometric curve fit is performed that determines the threshold (the standard deviation of the underlying cumulative Gaussian). Interaural translation refers to translations in the horizontal plane to the subject's left or right.; This outcome measure applies only to arm 5 subjects.	2 sessions separated by at least four days; measurements made 2 hrs after ingestion of medication
Primary	Percent Change in Manual Control Performance After Exposure to Hypogravity	Note that this applies to arms 6-9 only.; Subjects sat on a chair on a moving platform on top of a centrifuge that created an artificial gravity environment. Subjects completed a manual control task in which their charge was randomly perturbed in roll tilt, and they used a joystick to attempt to keep themselves aligned with upright, while in the dark. They did this while experiencing centripetal acceleration equivalent to Earth gravity (1 Gz), and then hypogravity (0.5 Gz). We calculated their performance by calculating the standard deviation of chair position across time, with a smaller number indicating better performance. Then we calculated the percent change in their performance between 1 Gz and 0.5 Gz.	1 session