Neuromodulation techniques have advanced significantly over the past 30 years, offering both non-invasive and invasive methods to influence the central nervous system. Non-invasive techniques include transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and transcranial ultrasound stimulation (TUS), while invasive methods include deep brain stimulation (DBS), spinal cord stimulation (SCS), and vagus nerve stimulation (VNS). These techniques are used for diagnostic and therapeutic purposes, with ongoing research uncovering new applications. TMS uses magnetic fields to induce electric currents in the brain, with applications in diagnosing and treating neurological and psychiatric disorders. Repetitive TMS (rTMS) is used for longer-lasting effects, with high-frequency rTMS increasing cortical excitability and low-frequency rTMS decreasing it. TMS has shown promise in treating depression, OCD, addiction, and other conditions. TMS can be combined with brain mapping and EEG for clinical and research applications. tDCS uses weak electric currents to modulate neural activity, with anodal stimulation increasing cortical excitability and cathodal stimulation decreasing it. tDCS has been used to treat psychiatric disorders like depression and schizophrenia, and has shown potential in improving motor and cognitive functions. However, its efficacy can be influenced by factors such as stimulation intensity and individual differences. tACS, a variant of tDCS, uses alternating currents to modulate cortical oscillations, with applications in cognitive enhancement and treating neurological disorders. It has shown promise in improving working memory and cognitive functions, and is being explored for personalized treatment protocols. TUS is a non-invasive technique that uses ultrasound to stimulate brain regions with high spatial resolution. It has been used to treat conditions like Parkinson's disease and epilepsy, with potential for improving motor function and cognitive performance. DBS involves implanting electrodes in the brain to deliver electrical stimulation, used primarily for movement disorders like Parkinson's disease. It is also approved for other conditions such as epilepsy and OCD. Closed-loop DBS systems are being developed to improve efficacy and reduce side effects. SCS is used for chronic neuropathic pain, with high-frequency stimulation showing effectiveness in some cases. It is also being explored for recovery after spinal cord injury and gait impairment in Parkinson's disease. VNS is used for treatment-resistant epilepsy and depression, with potential applications in inflammatory and autoimmune disorders. It works by stimulating the vagus nerve, which can modulate brain activity and reduce inflammation. These neuromodulation techniques continue to evolve, with ongoing research aimed at improving their efficacy and understanding their mechanisms. Clinicians must consider the evidence, advantages, and disadvantages of each technique when making treatment decisions.Neuromodulation techniques have advanced significantly over the past 30 years, offering both non-invasive and invasive methods to influence the central nervous system. Non-invasive techniques include transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and transcranial ultrasound stimulation (TUS), while invasive methods include deep brain stimulation (DBS), spinal cord stimulation (SCS), and vagus nerve stimulation (VNS). These techniques are used for diagnostic and therapeutic purposes, with ongoing research uncovering new applications. TMS uses magnetic fields to induce electric currents in the brain, with applications in diagnosing and treating neurological and psychiatric disorders. Repetitive TMS (rTMS) is used for longer-lasting effects, with high-frequency rTMS increasing cortical excitability and low-frequency rTMS decreasing it. TMS has shown promise in treating depression, OCD, addiction, and other conditions. TMS can be combined with brain mapping and EEG for clinical and research applications. tDCS uses weak electric currents to modulate neural activity, with anodal stimulation increasing cortical excitability and cathodal stimulation decreasing it. tDCS has been used to treat psychiatric disorders like depression and schizophrenia, and has shown potential in improving motor and cognitive functions. However, its efficacy can be influenced by factors such as stimulation intensity and individual differences. tACS, a variant of tDCS, uses alternating currents to modulate cortical oscillations, with applications in cognitive enhancement and treating neurological disorders. It has shown promise in improving working memory and cognitive functions, and is being explored for personalized treatment protocols. TUS is a non-invasive technique that uses ultrasound to stimulate brain regions with high spatial resolution. It has been used to treat conditions like Parkinson's disease and epilepsy, with potential for improving motor function and cognitive performance. DBS involves implanting electrodes in the brain to deliver electrical stimulation, used primarily for movement disorders like Parkinson's disease. It is also approved for other conditions such as epilepsy and OCD. Closed-loop DBS systems are being developed to improve efficacy and reduce side effects. SCS is used for chronic neuropathic pain, with high-frequency stimulation showing effectiveness in some cases. It is also being explored for recovery after spinal cord injury and gait impairment in Parkinson's disease. VNS is used for treatment-resistant epilepsy and depression, with potential applications in inflammatory and autoimmune disorders. It works by stimulating the vagus nerve, which can modulate brain activity and reduce inflammation. These neuromodulation techniques continue to evolve, with ongoing research aimed at improving their efficacy and understanding their mechanisms. Clinicians must consider the evidence, advantages, and disadvantages of each technique when making treatment decisions.