In this Introduction, I sketch out the rise of a transnational ethic of access to treatments for ill-health, and how it configures and is configured by mental healthcare in the UK. The instantiation of this ethic has resulted in policy and clinical attention to enhancing access to psychological therapy (often cognitive behavioural therapy, CBT, specifically). I introduce the importance of clinical psychology within this context and chart its consolidation as a profession, alongside a discussion of the role of CBT within the UK. I also discuss the wider entanglements of psychological praxis and societies, and the theoretical perspectives that propel the analysis presented in this book. I conclude with outlining the various chapters that follow.

This chapter tackles positron emission tomography (PET), a functional neuroimaging technique that revolutionized brain imaging in the 1970s by providing the first colorful maps of brain activity. Beginning with its historical development from Hans Berger’s early hemodynamic measurements to modern scanners, the chapter examines how PET visualizes metabolic processes by tracking radioactively labeled tracers in the bloodstream. Unlike structural imaging methods, PET detects gamma rays emitted when positrons from the radiotracer collide with electrons, allowing researchers to measure regional changes in blood flow, glucose metabolism, and neurotransmitter activity related to cognitive processes. The chapter details practical aspects of PET studies, including experimental design, data acquisition, image reconstruction techniques, and visualization methods like subtraction analysis for mapping task-related brain activity. While MRI-based techniques have supplanted PET for many cognitive neuroscience applications, PET remains invaluable for certain investigations due to its unique ability to label diverse compounds, particularly for studying neuropsychiatric disorders, neurotransmitter systems, and metabolic processes in diseases like Alzheimer’s and epilepsy.

The chapter investigates the persuasiveness of moral rhetoric, that is, effects on nonsupporters of the party. Based on insights from previous work, I develop theoretical expectations that suggest that moral rhetoric is unlikely to be persuasive, or make nonsupporters see the party more favorably. Previous studies on moral persuasion suggest moral-value alignment between a moral message and the recipient can make the message persuasive. Yet previous work on attitudinal bias suggest that moral rhetoric may be unpersuasive regardless of moral alignment and even further alienate nonsupporters with negative preexisting attitudes. I test the hypotheses using experiments in Britain. I find that moral rhetoric does not easily convince nonsupporters. However, moral rhetoric can be quite persuasive when the message is strong and the party has moral credibility. Under those conditions, moral rhetoric increases favorable attitudes, on average and among nonsupporters who prioritize the moral intuition in the message. There is no evidence that moral rhetoric further alienates hostile nonsupporters. The findings present a rather optimistic picture about the persuasiveness of moral rhetoric.

Chapter 7 deals with neuroimaging methods for investigating the structural components underlying brain function. Beginning with lesion-symptom mapping (LSM), which identifies relationships between localized brain damage and specific cognitive deficits, the chapter examines how structural abnormalities correlate with functional impairments. Three primary approaches to measuring brain structures with MRI are discussed: structure tracing for hypothesis-driven volumetric analysis, voxel-based morphometry (VBM) for whole-brain comparison of tissue concentration, and surface-based morphometry (SBM) for analyzing the cortical sheet’s unique properties including thickness, curvature, and gyrification. The chapter then explores diffusion tensor imaging (DTI), a technique that visualizes white-matter tracts by measuring the anisotropic diffusion of water molecules along axon bundles. DTI tractography reveals the brain’s “highways,” short, intermediate, and long-range fiber pathways that connect functional modules within and across hemispheres. Together, these complementary techniques provide critical insights into the structural architecture supporting brain networks, offering a more complete understanding of brain organization when combined with functional imaging methods.

Chapter 9 introduces transcranial magnetic stimulation (TMS), a neurostimulation technique that uses rapidly changing magnetic fields to induce electric currents in targeted brain regions. Beginning with its historical roots in 19th-century electromagnetic experiments and evolving through Anthony Barker’s groundbreaking 1985 demonstration, TMS has become a critical tool for establishing causal relationships between brain activity and behavior. Unlike neuroimaging methods that only observe brain activity, TMS can temporarily interrupt or enhance neural processing, enabling researchers to create “virtual lesions” and directly test hypotheses about regional brain function. The chapter examines TMS delivery methods, single-pulse, paired-pulse, and repetitive stimulation, and their differential effects on cortical excitability. It details four primary research applications: virtual lesions for establishing causality, chronometry for determining processing timelines, mapping functional connectivity between brain regions, and tracking neuroplasticity. Clinical applications are discussed, particularly for treating depression and presurgical mapping. The chapter also addresses practical aspects of TMS implementation, localization techniques, and safety considerations, concluding with a brief overview of transcranial direct current stimulation (tDCS) as a milder alternative stimulation approach.

Chapter 2 traces the development of electroencephalography (EEG) from its inception with Richard Caton’s pioneering work in 1875 to its current status as a cornerstone of human neuroimaging. The chapter discusses how EEG captures the electrical signals generated by synchronous activity of pyramidal neurons arranged in open fields perpendicular to the cortical surface. It examines the technical evolution of recording systems, from basic silver-chloride electrodes to modern active electrode arrays with built-in amplification, and explains the standardized 10-20 electrode placement system that enables spatial mapping of brain activity. The chapter addresses the inverse problem that constrains EEG’s spatial resolution while highlighting its exceptional temporal precision for tracking neuronal events in millisecond timescales. Special attention is given to the characteristic oscillatory patterns in different frequency bands (alpha, beta, theta, delta, gamma) and their association with cognitive states ranging from deep sleep to focused attention. The chapter details practical considerations for obtaining clean recordings, including artifact reduction techniques and experimental design. By evaluating EEG’s strengths (temporal precision, direct measurement of neural activity, accessibility) alongside its limitations, the chapter positions EEG as an enduring, versatile tool for both clinical applications and cognitive neuroscience research despite technological advances in other imaging modalities.

Chapter 5 examines the representational role of moral rhetoric. Moral rhetoric can be considered parties’ attempts to signal that they represent the moral values of the electorate. If so, how important is moral rhetoric as a form of moral representation? I answer this question by examining people’s attitudes about moral rhetoric in politics. I theorize that many voters want some level of moral discourse in politics, although there is variation in attitudes. I further theorize that demand for a party’s moral rhetoric exists not only among voters who support the party but also among voters who appreciate moral reasoning in politics, even if they do not support the party. Survey data from six countries show that many voters indeed want to see moral discourse in politics. Moreover, voters’ demands for moral rhetoric have partisan and nonpartisan antecedents. A voter’s copartisan status with the party positively predicts greater demand for moral rhetoric, but so does a voter’s reliance on moral reasoning when thinking about politics, holding partisanship constant. In short, we learn that moral rhetoric has representational significance for broad groups of the electorate.