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Investigation of Cortico-Rectal Pathways in Healthy Subjects (Aim 2)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified January 2014 by Satish Rao, Georgia Regents University.
Recruitment status was:  Active, not recruiting
Information provided by (Responsible Party):
Satish Rao, Georgia Regents University Identifier:
First received: August 18, 2010
Last updated: January 8, 2014
Last verified: January 2014
Biofeedback therapy improves bowel symptoms and anorectal function in patients with dyssynergic defecation, however its mechanism of action is not known. The investigators hypothesize that biofeedback therapy enhances gut-brain-gut communication by altering cortical processing of information and improving cortically mediated neuromuscular function of the gut. However, in order to better understand these mechanisms in patients, the investigators need to examine and establish normative data and compare findings with healthy subjects. The investigators specific aims are to examine and evaluate the following 40 normal subjects; (1) To evaluate the afferent cortical evoked potentials in response to the electrical stimulation of the anorectum and (2) To evaluate the corticofugal tracts (efferent) by recording the anal and rectal electromyographic responses following noninvasive lumbosacral and transcranial magnetic stimulation.

Healthy Volunteers

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Investigation of Cortico-Rectal Pathways in Healthy Subjects

Further study details as provided by Satish Rao, Georgia Regents University:

Primary Outcome Measures:
  • Describe latencies and amplitudes between the brain and gut in healthy volunteers [ Time Frame: 1 visit of 3 hours ]

    Measurements & Analysis: The latency, inter-peak latency and amplitude of each component of the cortical evoked potentials will be averaged to obtain group mean data.

    Statistical Analysis: The paired t-test or Wilcoxon signed-rank test will be used to compare the latencies.

    Lumbosacral and Transcranial Magnetic Stimulation (TMS) Data and Statistical Analysis: Mean latency and mean amplitude for each individual will be calculated.

Estimated Enrollment: 50
Study Start Date: August 2005
Estimated Study Completion Date: June 2014
Estimated Primary Completion Date: March 2014 (Final data collection date for primary outcome measure)
Healthy Volunteer


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population
40 Healthy volunteers.

Inclusion criteria:

  • Right-handed adults between ages 18 years and 99 years, who are free of bowel disorders or other medical illnesses.

Exclusion Criteria:

  • Potential subjects with comorbid illnesses; severe cardiac disease, chronic renal failure or previous gastrointestinal surgery except cholecystectomy and appendectomy.
  • Neurologic diseases e.g.; head injury, epilepsy, multiple sclerosis, strokes, spinal cord injuries.
  • People who have metal in their skull or under the skull, or have metal in the back or hips.
  • People who have a cardiac pacemaker, implanted defibrillator or medication pump.
  • Impaired cognizance (mini mental score of < 15) and/or legally blind.
  • Pregnant or likely to conceive during the course of the study. Women with potential for pregnancy must be willing to use contraceptive measures during the study.
  • Previous pelvic surgery, rectocele repair, bladder repair, radical hysterectomy.
  • Rectal prolapse or anal fissure or anal surgery.
  Contacts and Locations
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Please refer to this study by its identifier: NCT01300897

United States, Iowa
University of Iowa Hospitals and Clinics
Iowa City, Iowa, United States, 52242
Sponsors and Collaborators
Augusta University
Principal Investigator: Satish SC Rao, MD, PhD Augusta University
  More Information

Responsible Party: Satish Rao, Professor, Georgia Regents University Identifier: NCT01300897     History of Changes
Other Study ID Numbers: 5R01DK057100-2
5R01DK057100 ( U.S. NIH Grant/Contract )
Study First Received: August 18, 2010
Last Updated: January 8, 2014

Keywords provided by Satish Rao, Georgia Regents University:
cortical function, motor evoked potential responses processed this record on July 19, 2017