Otto Lowenstein: neurologic and ophthalmologic testing methods during his lifetime.
Lowenstein's work on the pupil is well known in this country and in Europe. It constituted, however, only one of many of his fields of interest. In all of them his contributions were based on experiments in which accurate, objective recording replaced mere observation with the unaided eye. The resulting traces, obtained under stable conditions and with well-defined stimuli, revealed specific normal or pathologic reaction patterns, and these, in turn, allowed recognition, quantification and localization of the underlying physiologic mechanisms or pathologic defects. During the early decades of this century Lowenstein invented and built his own instruments. And as more advanced technical means became available, he adopted these, so that his methods became more elegant and less time-consuming. This history forms an interesting parallel to the development of work done by others throughout the twentieth century.