EEG-Neurofeedback Training and Prolidase in Anxiety Disorders: An Exploratory Study

  • Pratibha Meena, Ms PhD Scholar, Dept. of Clinical Psychology
  • Sarada Subramanian, Dr. National Institute of Mental Health and Neurosciences
  • Geetha Desai, Dr. National Institute of Mental Health and Neurosciences
  • Geethu Krishna, Ms National Institute of Mental Health and Neurosciences
  • Jamuna Rajeswaran National Institute of Mental Health and Neurosciences
Keywords: anxiety disorders, prolidase, proline, EEG-neurofeedback training, neurocognitive functions, executive functions


Objective: Prolidase is an enzyme that releases proline and is vital in extracellular matrix (ECM) remodeling, fueling white matter dynamics. Serum prolidase activity (SPA) is elevated in various neuropsychiatric conditions and may influence cognitive functions. Aim of the study was to explore the relation of SPA to neuropsychological functioning and its response to treatment in anxiety disorders. Methods: Twenty demographic-matched patients with anxiety were recruited. Six patients were given EEG-neurofeedback training (EEG-NFT), eight were treated pharmacologically (treatment as usual; TAU) with EEG-NFT, and six patients were treated only pharmacologically (TAU group). Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) were used to assess anxiety and comorbid depression, respectively. Results: Symptom reduction was seen in all groups. SPA decreased considerably in EEG-NFT group. Mental speed and spatial working memory negatively correlated with SPA in EEG-NFT group. Focused attention, sustained attention, verbal working memory, and spatial construction ability negatively correlated with SPA in EEG-NFT+TAU group. Mental speed in TAU group was also inversely proportional to SPA. Conclusion: Inverse correlation between SPA and neuropsychological functions in EEG-NFT group is suggestive of prolidase-mediated microstructural changes in white matter, which may have an influence on cognitive enhancement in anxiety disorders (AD).


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