To understand the function and dynamics of the nervous system and to find treatments for the neurological and psychiatric conditions that increasingly affect our aging society, new tools capable of addressing neuronal signaling complexity are urgently needed. These tools must also match the mechanical and chemical properties of the neural tissue to avoid functional perturbation to local circuits. By leveraging fiber drawing, our group creates flexible and stretchable probes capable of recording and stimulation of neural activity as well as delivery of drugs and genes into the brain and spinal cord. We use these probes to interrogate brain circuits, such as those involved in anxiety and fear, and to promote recovery following spinal cord and nerve injury. Simultaneosly, we develop a broad range of magnetic nanotransducers that convert externally applied magnetic fields into thermal, chemical, and mechanical signals, which can then be perceived by ion channels on neurons. Since biological tissues exhibit negligible magnetic permeability and low conductivity, magnetic fields can penetrate deep into the body with no attenuation allowing us to apply the nanomagnetic transducers to remotely control deep brain circuits associated with reward and motivation as well as adrenal circuits involved in regulation of stress hormones.