Dr. Dhanjal is a highly experienced consultant neurologist based at the National Hospital for Neurology and Neurosurgery in London, where he runs specialist clinics for cognitive disorders and general neurology, as well as headache clinics. He earned his medical degree from Guy's, King's, and St. Thomas' School of Medicine in London before completing an intercalated BSc in pharmacology. He then gained a place on the Hammersmith Hospital medical rotation programme and undertook general medicine training at various hospitals, including the Royal Brompton and Royal Free hospitals.

Dr. Dhanjal used functional magnetic resonance imaging technology as a clinical research fellow to investigate verbal episodic memory function in patients with Alzheimer's disease and mild cognitive impairment. He later secured a clinical research training fellowship from the UK-based Medical Research Council so that he could complete his PhD studies at Imperial College London. He went on to receive extensive training in neurology at a number of hospitals before joining the National Hospital for Neurology and Neurosurgery.