Principles of Psychophysiology: Physical, Social, and Inferential Elements

The book's spine is Cacioppo and Tassinary's taxonomy of psychophysiological relations, developed more fully in their 1990 American Psychologist article. They argue that physiological signals relate to psychological operations in four distinct ways: outcomes (physiological responses that follow from psychological events), concomitants (responses that co-occur without causal priority), markers (responses that indicate the presence of a psychological state without being part of it), and invariants (responses that map one-to-one onto psychological operations). The framework demands that researchers specify the specificity and generality of any claimed relation before interpreting data. This taxonomy became the field's standard for evaluating whether a physiological measure can bear the inferential weight placed on it.

Principles (1990) was revised and expanded into the second edition of the Handbook of Psychophysiology (2000), marking the transition from a single-volume treatise to a continuously updated reference work . The first edition of the Handbook retained the core inferential framework while adding Gary Berntson as a third editor and expanding coverage of central nervous system methods. The Principles volume is now primarily of historical interest for tracing how the field's foundational inference model was first assembled, while the Handbook serves as the current reference. Researchers citing the inferential taxonomy typically cite the 1990 American Psychologist article rather than the book chapter itself.

The book organizes systemic coverage across the skeletomotor (surface electromyography), electrodermal, cardiovascular, electrocortical, event-related brain potential, ocular, gastrointestinal, pulmonary, sexual response, and verbal systems . Each chapter provides a tutorial on measurement principles, signal characteristics, and interpretive cautions specific to that system. The volume also includes foundational chapters on neuroscience, bioelectrical measurement, psychoneuroendocrinology, psychoneuroimmunology, and interoception. This structure—foundations, general concepts, systemic tutorials, and analytic procedures—became the template for subsequent editions, though the balance has shifted toward central nervous system methods in later volumes.

Contemporary reviews were strongly positive, with Brett Clementz writing in Contemporary Psychology that it was 'brilliantly planned and beautifully executed' and 'without peer' . Jordan Grafman, reviewing in the International Journal of Clinical Neuropsychology, called it 'a model volume of this type' useful for advanced undergraduates and beginning graduate students . James Kalat in American Scientist noted its 'strong how-to-do-it emphasis' and its insistence that investigators understand both psychological and physiological issues . The book filled a recognized gap: no single volume had previously reviewed psychophysiology at a level both informative to specialists and accessible to nonspecialists .

The volume does not focus on consumer behavior, but Cacioppo's concurrent work with Richard Petty on the Elaboration Likelihood Model of persuasion—developed during the same period—makes the inferential framework relevant to attitude research. The book's insistence on specifying the psychological operation before selecting physiological measures applies directly to consumer neuroscience, where researchers often claim to measure 'preference' or 'attention' without defining those constructs operationally. Its placement in Consumer Psychology reflects the broader significance of Cacioppo's inferential rigor for any domain that uses physiological measures to index psychological states, including persuasion and preference formation.