Neuromodulation refers to the process by which certain substances or signals influence the activity of neurons in the brain and nervous system. This can involve the release of neurotransmitters, which are chemicals that transmit signals between nerve cells, or the use of devices that stimulate specific areas of the brain. Neuromodulation plays a crucial role in regulating various functions, including mood, pain perception, and motor control. Techniques for neuromodulation include deep brain stimulation, transcranial magnetic stimulation, and pharmacological interventions. These methods can be used to treat a range of conditions, such as depression, chronic pain, and Parkinson's disease. By altering neuronal activity, neuromodulation can help restore balance in the nervous system and improve overall health.