Inclusion Criteria - Controls:

• Healthy volunteers aged 18-80 years old
• Able to provide written informed consent before participating in the study.
• Able to communicate adequately with the investigator and to comply with the requirements for the entire study.

Inclusion Criteria - Constipated Patients:

• Male and female volunteers aged 18-80 years.
• Individuals with chronic constipation for 1 year, with 2 or more of the following symptoms for 3 months or longer: < 3 bowel motions/week, straining ≥ 25% of time, hard or lumpy stools ≥ 25% of time, anal digitation ≥ 25% of time, incomplete evacuation ≥ 25% of time, feeling of anorectal blockage ≥ 25% of time.
• Able to provide written informed consent before participating in the study.
• Able to communicate adequately with the investigator and to comply with the requirements for the entire study.

Exclusion Criteria - Controls:

Items marked with an asterisk also apply to patients

• Clinical evidence of significant cardiovascular, respiratory, renal, hepatic, gastrointestinal, hematological, neurological, psychiatric or other disease that may interfere with the objectives of the study and/or pose safety concerns.*
• Current symptoms of a functional gastrointestinal disorder assessed by questionnaire.
• Putative risk factors for pelvic floor trauma; i.e., six or more vaginal deliveries, birthweight > 4500gms (macrosomia), or known 3rd or 4th degree perineal tear.
• Medications that are likely to alter gastrointestinal motility: e.g., opiates and  anticholinergic medications; a stable dose of thyroxine and low doses of tricyclic agents (e.g., up to amitriptyline (50 mg daily).
• Active rectal inflammation, cancer; perianal sepsis; history of pelvic radiation in the past 3 years, rectal resection, or inflammatory bowel disease.*
• Anxiety or depression as assessed by the Hospital Anxiety and Depression Questionnaire.
• Pregnant women, prisoners and institutionalized individuals.*
• Patients with safety contraindications to routine clinical 7T MRI as determined by the Mayo Clinic Rochester MR Safety Committee.*
• Claustrophobic patients that cannot undergo MRI without anxiolytic medication.*
• Patients with known vestibular dysfunction.*     

Additional General Exclusion Criteria for 7T task fMRI:

All subjects and controls will be excluded from undergoing the task fMRI scan if they have:

• Active implant devices such as cardiac defibrillators/pacemakers, heart monitors, cohlear implants.
• Abandoned cardiac pacer wires.
• Orthopedic implants that are near the spinal cord or temperature sensitive organs.
• Metallic implants near the orbits.
• External devices that cannot be removed from the body (such as medicinal patches, piercings, jewelry, clothing or hair accessories).
• Temporary tattoos or those obtained prior to 1995.
• Colored contact lens.
• Any ‘undefined’ metallic implants of foreign bodies inside the patient.
• Are pregnant.