For over 50 years, ketamine has been known as a safe anesthetic, and at lower doses, an effective treatment for depression. Emerging research suggests it may also enhance cognition and neuroplasticity, offering hope for patients with neurological disorders such as Parkinson’s, multiple sclerosis, and brain injury. Animal studies show ketamine promotes synaptogenesis and improved memory, while human research remains limited. Combining ketamine with cognitive rehabilitation may enable not only symptom relief but also potential restoration of lost cognitive function.