Provider Bio

Mariah Corneille, PsyD

Lead Gut-Brain Specialist

A licensed clinical psychologist with expertise in medical and health psychology, Dr. Mariah Corneille helps people address the mind-body connection to optimize overall health and wellness. 

Mariah collaborates across integrated care teams to support patients with intersecting medical and behavioral health concerns, including treating a wide range of GI conditions. She has more than 10 years of experience 
working in both inpatient and outpatient medical settings.

At Oshi Health, Mariah helps patients understand and manage the relationship between their gut and their brain using targeted, evidence-based practices—such as relaxation training, mindfulness, cognitive behavioral therapy (CBT), and acceptance and commitment therapy (ACT) specifically designed for digestive health. 

Mariah is passionate about providing patient-centered care with a culturally-informed lens to help people achieve positive health outcomes. She also gained clinical leadership experience at a VA medical center, where she was the lead clinician in a primary care integrated health clinic, and supported hospital-wide initiatives focused on Diversity and Inclusion, such as improving access to healthcare. 

Outside of her practice, Mariah embraces the vibrant lifestyle of sunny South Florida, such as moments at the beach with her family. She enjoys the combination of mindfulness with cooking and indulging in reality television—finding balance and rejuvenation in these simple pleasures.

“I honor the inseparable bond between the gut and the mind in digestive health. I believe in addressing the whole person, recognizing that true wellness stems from nurturing both physical and mental health, and that neglecting this connection undermines mind-body healing.”

Favorite gut health tip

Exploring methods to relax the mind not only alleviates stress but also soothes the gut, fostering a harmonious balance crucial for optimal digestive wellness.


  • Medical education: Albizu University, Doctor of Psychology (PsyD), Health Psychology emphasis
  • Advanced Clinical Practicum: University of Miami Miller School of Medicine, Medical Psychology and Psychopharmacology
  • Residency: University of Missouri-Columbia, Health Psychology
  • Fellowship: Miami VA Healthcare System, Health Psychology-Integrated Care


  • American Psychological Association, Division 38 – Society for Health Psychology
  • Rome Foundation GastroPsych
  • National Register of Health Service Psychologists