Receptor Specificity

　The problems of receptor specificity are of considerable general interest and may be considered from several aspects：From a biophysical or physiological standpoint，specificity implies a differential sensitivity of a receptor to various types of stimuli, i. e.，mechanical, thermal, chemical or light. From a structural aspect morphological differentiation is often considered as an index of specificity. The psychophysical approach considers specificity, particularly in cutaneous sensation, as being concerned with perceived modalities of sensation. It is useful to distinguish these several aspects of the problem.