The issue of primary tastes versus a taste continuum

The concept of four primary tastes has been used to direct research and organize data in gustation. The attractive simplicity of this formulation has directed attention away from critical examinations of its validity. The present article shows that arguments used to support the concept of four tastes are equivocal. It is also suggested that the data are more consistent with the hypothesis that gustatory data have a more continuous organization which includes the familial primary four. Data are considered at the stimulus, receptor, neural, and psychophysical levels.