A randomized controlled trial investigated the effects of adding whole-brain radiation therapy (WBRT) to stereotactic radiosurgery (SRS) for patients with newly diagnosed brain metastases. Results indicated that patients receiving SRS alone experienced less cognitive decline compared to those receiving SRS plus WBRT, with a notable difference in learning and memory function after four months. The study supports using SRS as a preferred treatment strategy to better preserve neurocognitive function in these patients.