The goal of affective neuroscience research is to integrate as many measures as possible when attempting to gauge affective experience. This chapter examines the value of objective and subjective measures used in affective neuroscience. It presents examples that showcase the use of the response indices, illustrating how objective and subjective measures operate uniquely and offer opportunities to investigate the properties of emotion from different vantage points. The chapter addresses some limitations to measurement and comments on work that is pushing research forward by combining measures with inventive methods. Future research that investigates deeply experiential aspects of the human emotional life will benefit from employing a network of measures to provide a more in-depth understanding of the neurophenomenology of emotion. The challenge before affective neuroscientists is to include and integrate multiple indices from both subjective and objective categories of measurement to best capture the mental and neural bases of emotional life.

Psychologists and neuroscientists began to build bridges and linked their inquiries together. Both philosophers and scientists employ the term reduction in characterizing relations between the results of higher-level and basic-level inquiries that are supposedly jeopardized by multiple realization. This chapter describes an understanding of reduction provided by the framework of mechanistic explanation that fits with the pursuit's scientists label reductionistic. There are differences between the mechanisms in different species that result in what are treated as the same phenomena. The chapter takes up this issue directly and discusses that the same standards of typing are applied to phenomena as to realizations. It considers what happens when one uses a coarser grain to type neural phenomena. The chapter presents the research on circadian rhythms as an exemplar as this is a field in which the issues concerning multiple realization, conservation of mechanism, and identity.