Helmholtz's research also aided in the scientific understanding of psychophysiological processes; both discoveries prove to be very useful for understanding the mind-body relationship. Weber, in his study of the senses, tested muscular sensations and cutaneous senses through the two-point threshold and the barely perceptible difference. His research revealed that there could be no direct connection between our perception of a physical stimulus and the stimulus itself. In the study and analysis of the senses, Fechner introduced the idea of ​​a differential threshold with the aim of drawing a line between the intensity of the stimulus and the sensation values ​​that would derive from it. Fechner also studied the relationship between material stimuli and mental sensations. Fechner's work in Psychophysics brought together the work of Descartes and all the scientists whose work contributed to a mind-body upgrade