Catheter apparatuses, systems, and methods for achieving neuromodulation by intravascular access are disclosed herein. One aspect of the present technology, for example, is directed to a treatment device having a therapeutic assembly that includes an elongated tubular shaft having a pre-formed spiral shape when in a deployed state (e.g., a radially expanded, generally spiral/helical shape) and a thermocouple assembly helically wrapped about the shaft. In one embodiment, the thermocouple assembly comprises first and second wires composed of dissimilar metals with the first wire including a plurality of exposed and insulated regions along the distal portion of the treatment device. The exposed regions of the first wire define a plurality of energy delivery portions positioned to deliver electrical energy (e.g., RF energy, pulsed energy, etc.) to target tissue adjacent a wall of an artery (e.g., a renal artery) to heat or otherwise electrically modulate neural fibers that contribute to physiological function (e.g., renal function).