Implanted neural sensing is important to unravel the complexity of neuronal circuitries and understand brain function. Implanted neural devices can capture neurochemical signals in the brain real time. During chronic implantation, micromotion between the neural implant and brain tissue is considered as one of key drivers for immune response and astroglial sheath formation around implants. Therefore, micromotion during in-vivo experiments interfere electrochemical sensing signals and longevity in the brain. This research presents experimental design and results of electrochemical and mechanical coupling of micromotion in a brain-like phantom simulating the brain. A piezoelectric actuator was used to generate motion of an electrode implanted in a phantom while applying potentials for cyclic voltammetry. Electrochemical signal analysis of neurotransmitter sensing was performed to identify motional effects varying experimental conditions such as the frequency and amplitude of mechanical motion, and the chemical and mechanical properties of the brain-like phantom changing the concentration of gelatin. The mechanical effect on neural sensing was also analyzed using DFT. We also introduced a computational model of micromotion in the brain to simulate and analyze mechanical effects on electrochemical neural sensing. The experiment and simulation results show mechanical motion affects the current level in the redox peaks of CV the most, and also shifts the peak voltages.