In memory of our mentor: Frans de Waal (1948-2024).

The world lost a towering figure when primatologist Frans de Waal passed away on March 14, 2024. Many are aware of his multitude of contributions to the field. His ability to see what animals were actually doing changed how we viewed first primates, then other species. He shared these insights through both traditional scientific outputs, such as journal articles and scientific presentations, and less common outputs, such as 15 books and two TED talks viewed millions of times. What may be less well known is his impact as a mentor. Here, 25 of us who were Frans' graduate students, postdocs, and long-term research assistants share his personal impact on our lives.

The Reasoning through Evidence versus Advice (EvA) Scale: Scale Development and Validation.

Our well-being can improve when people heed evidence rather than simply follow familiar or charismatic advisors who neglect evidence. We developed the Reasoning through Evidence versus Advice (EvA) scale to measure individual differences in reasoning through evidence like science and statistics versus following advisors such as politicians and celebrities. No existing scales directly measure these tendencies; moreover, it was theoretically unknown whether they reflect a single dimension (from evidence- to advice-based) or distinct tendencies to value or distrust each. Our scale validation process included qualitative interviews and four studies that involved 1583 respondents (753 college graduates, 830 non-college graduates) in which we conducted exploratory and confirmatory factor analyses and tests of convergent validity, discriminant validity, and measurement invariance by gender and education. This process yielded a 16-item EvA scale with four dimensions: Pro-evidence, Anti-evidence, Pro-advice, and Anti-advice. In assessing criterion validity, these tendencies identified individual differences in important, real-world attitudes and behaviors, including susceptibility to health misinformation, adherence to CDC guidelines on social distancing, confidence in the COVID vaccine, science curiosity, and religiosity. The EvA scale extends our understanding of individual differences in reasoning tendencies that shape critical attitudes, decisions, and behaviors and can help promote informed decisions.

Using effective psychological techniques to subvert a US sociopolitical context.

Chater & Loewenstein argue for a shift in focus from individual- to structural-level approaches to societal ills. This is valid and important but overlooks the barriers inherent in the current US partisan context. Psychology can be applied to help people of mixed allyship join together, to effectively and quickly force institutions and corporations to accept structural change.

Mammalian empathy: behavioural manifestations and neural basis.

Recent research on empathy in humans and other mammals seeks to dissociate emotional and cognitive empathy. These forms, however, remain interconnected in evolution, across species and at the level of neural mechanisms. New data have facilitated the development of empathy models such as the perception-action model (PAM) and mirror-neuron theories. According to the PAM, the emotional states of others are understood through personal, embodied representations that allow empathy and accuracy to increase based on the observer's past experiences. In this Review, we discuss the latest evidence from studies carried out across a wide range of species, including studies on yawn contagion, consolation, aid-giving and contagious physiological affect, and we summarize neuroscientific data on representations related to another's state.

Emotion and reward are dissociable from error during motor learning.

Although emotion is known to reciprocally interact with cognitive and motor performance, contemporary theories of motor learning do not specifically consider how dynamic variations in a learner's affective state may influence motor performance during motor learning. Using a prism adaptation paradigm, we assessed emotion during motor learning on a trial-by-trial basis. We designed two dart-throwing experiments to dissociate motor performance and reward outcomes by giving participants maximum points for accurate throws and reduced points for throws that hit zones away from the target (i.e., "accidental points"). Experiment 1 dissociated motor performance from emotional responses and found that affective ratings tracked points earned more closely than error magnitude. Further, both reward and error uniquely contributed to motor learning, as indexed by the change in error from one trial to the next. Experiment 2 manipulated accidental point locations vertically, whereas prism displacement remained horizontal. Results demonstrated that reward could bias motor performance even when concurrent sensorimotor adaptation was taking place in a perpendicular direction. Thus, these experiments demonstrate that affective states were dissociable from error magnitude during motor learning and that affect more closely tracked points earned. Our findings further implicate reward as another factor, other than error, that contributes to motor learning, suggesting the importance of incorporating affective states into models of motor learning.

Environmental impassivity: Blunted emotionality undermines concern for the environment.

The average American believes in climate change, worries about it, and supports related policy, but there are still considerable differences-across individuals and with political ideology-that limit the ability to foster change. Researchers and practitioners often increase concern and action for others through feelings of empathy, which also increases pro-environmentalism. However, some people appear less emotionally impacted by environmental destruction-particularly more ideologically conservative and less pro-environmental individuals. To determine why some people appear to be impassive to environmental destruction, we conducted 3 online studies to measure beliefs and emotional processes in political liberals versus conservatives. Across 3 studies, we replicated the link between impassivity and conservatism, and found that more impassive people acknowledge our negative impact on the environment but are less concerned about it and more confident in an eventual solution. Impassivity, however, is not specific to the environment. People who are more impassive about the environment also respond less emotionally to positive and negative images that are unrelated to the environment, including human suffering and hedonic reward. They also report reduced trait empathy, perspective taking, and daily emotional expression and experience. Impassivity is not linked to differences in trait personal distress, anxiety, psychopathy (apart from low empathy), or trouble appreciating consequences. Impassivity is not associated with deficits in processing others' facial emotion during early perceptual decoding but is associated with the later suppression of emotion. Everyone will not respond to emotional appeals to help a distressed environment. Other strategies are recommended to reach a broad audience. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Below the surface of a touch.

How the body and brain respond to a gentle stroke dynamically changes depending on how familiar someone is with the other person.

Neural correlates of overvaluation and the effort to save possessions in a novel decision task: An exploratory fMRI study.

Introduction: People exhibit a strong attachment to possessions, observed in behavioral economics through loss aversion using new items in the Endowment or IKEA effects and in clinical psychology through pathological trouble discarding domestic items in Hoarding Disorder. These fields rarely intersect, but both document a reticence to relinquish a possessed item, even at a cost, which is associated with feelings of loss but can include enhanced positive states as well. Methods: To demonstrate the shared properties of these loss-related ownership effects, we developed the Pretzel Decorating Task (PDT), which concurrently measures overvaluation of one's own over others' items and feelings of loss associated with losing a possession, alongside enhanced positive appraisals of one's items and an effort to save them. The PDT was piloted with 31 participants who decorated pretzels and responded to their own or others' items during functional neuroimaging (fMRI). Participants observed one item per trial (self or other) and could work to save it (high or low probability loss) before learning the fate of the item (trashed or saved). Finally, participants rated items and completed hoarding tendency scales. Results: The hypotheses were supported, as even non-clinical participants overvalued, viewed as nicer, feared losing, and worked harder to save their items over others'-a response that correlated with hoarding tendencies and motor-motivational brain activation. Our region of interest in the nucleus accumbens (NAcc) was engaged when viewing one's own items to the extent that people worked harder to save them and was more active when their items were saved when they felt emotionally attached to possessions in real life. When their items were trashed, NAcc activity negatively correlated with trouble discarding and emotional attachments to possessions. Right anterior insula was more active when working to save one's own over others' items. Extensive motor-motivational areas were engaged when working to save one's own over others' items, including cerebellum, primary motor and somatosensory regions, and retrosplenial/parahippocampal regions-even after controlling for tapping. Discussion: Our attachments to items are emotional, continuous across typical and pathological populations, and drive us to save possessions that we value.

Altruistic responses to the most vulnerable involve sensorimotor processes.

Introduction: Why do people help strangers? Prior research suggests that empathy motivates bystanders to respond to victims in distress. However, this work has revealed relatively little about the role of the motor system in human altruism, even though altruism is thought to have originated as an active, physical response to close others in immediate need. We therefore investigated whether a motor preparatory response contributes to costly helping. Methods: To accomplish this objective, we contrasted three charity conditions that were more versus less likely to elicit an active motor response, based on the Altruistic Response Model. These conditions described charities that (1) aided neonates versus adults, (2) aided victims requiring immediate versus preparatory support, and (3) provided heroic versus nurturant aid. We hypothesized that observing neonates in immediate need would elicit stronger brain activation in motor-preparatory regions. Results: Consistent with an evolutionary, caregiving-based theory of altruism, participants donated the most to charities that provided neonates with immediate, nurturant aid. Critically, this three-way donation interaction was associated with increased BOLD signal and gray matter volume in motor-preparatory regions, which we identified in an independent motor retrieval task. Discussion: These findings advance the field of altruism by shifting the spotlight from passive emotional states toward action processes that evolved to protect the most vulnerable members of our group.

Opening the Black Box of Family-Based Treatments: An Artificial Intelligence Framework to Examine Therapeutic Alliance and Therapist Empathy.

The evidence-based treatment (EBT) movement has primarily focused on core intervention content or treatment fidelity and has largely ignored practitioner skills to manage interpersonal process issues that emerge during treatment, especially with difficult-to-treat adolescents (delinquent, substance-using, medical non-adherence) and those of color. A chief complaint of "real world" practitioners about manualized treatments is the lack of correspondence between following a manual and managing microsocial interpersonal processes (e.g. negative affect) that arise in treating "real world clients." Although family-based EBTs share core similarities (e.g. focus on family interactions, emphasis on practitioner engagement, family involvement), most of these treatments do not have an evidence base regarding common implementation and treatment process problems that practitioners experience in delivering particular models, especially in mid-treatment when demands on families to change their behavior is greatest in treatment - a lack that characterizes the field as a whole. Failure to effectively address common interpersonal processes with difficult-to-treat families likely undermines treatment fidelity and sustained use of EBTs, treatment outcome, and contributes to treatment dropout and treatment nonadherence. Recent advancements in wearables, sensing technologies, multivariate time-series analyses, and machine learning allow scientists to make significant advancements in the study of psychotherapy processes by looking "under the skin" of the provider-client interpersonal interactions that define therapeutic alliance, empathy, and empathic accuracy, along with the predictive validity of these therapy processes (therapeutic alliance, therapist empathy) to treatment outcome. Moreover, assessment of these processes can be extended to develop procedures for training providers to manage difficult interpersonal processes while maintaining a physiological profile that is consistent with astute skills in psychotherapeutic processes. This paper argues for opening the "black box" of therapy to advance the science of evidence-based psychotherapy by examining the clinical interior of evidence-based treatments to develop the next generation of audit- and feedback- (i.e., systemic review of professional performance) supervision systems.

The meaning in empathy: distinguishing conceptual encoding from facial mimicry, trait empathy, and attention to emotion.

In order to truly empathise with another, we need to recognise and understand how they feel. Perception-action models of empathy predict that attending to another's emotion will spontaneously activate the observer's own conceptual knowledge for the state, but it is unclear how this activation is related to facial mimicry, trait empathy, or attention to emotion more generally. In the current study, participants did spontaneously encode background facial expressions at a conceptual level even though they were irrelevant to the task (the Emostroop effect; Preston & Stansfield, 2008), but this encoding was not associated with mimicry of the faces, trait empathy, the ability to resolve competing semantic representations (Colour-naming Stroop task), or the tendency to be distracted by emotional information more generally (Intrusive Cognitions task). Our results suggest that trait empathy increases attention to emotional information, but conceptual encoding occurs across individuals as a natural consequence of attended perception.

Object attachment and decision-making.

The perceived value of our possessions extends well beyond their monetary worth or utility. Many possessions produce abiding attachments and contain deep conceptual meanings, which strongly influence our drive to acquire, retain, or relinquish them. In both the endowment effect and hoarding disorder (HD) research had focused on the degree that a fear of loss produces overvaluation by owners. There is evidence for this at both the behavioral and neural level, for example with self-reported negative emotions and activation in the insula and anterior cingulate cortex when one struggles to relinquish a good. However, there is also evidence from both fields that positive appraisals, motivations, and attachments participate in this process, with supporting activation in the dopaminergic mesolimbocortical system (e.g. nucleus accumbens and orbitofrontal cortex). These processes appear continuous between typical and clinical populations and with decisions about rewarding items in other contexts and species, such as food storing in rodents and offspring care in mammals. More research is needed on the degree that our attachment to and protection of goods reflect ancient neural systems for offspring care. We also need to study participants from other demographics and levels of wealth, and to consider how task framing shifts the proportion of associated negative and positive emotional states.

Understanding empathy and its disorders through a focus on the neural mechanism.

Empathy is a complex, multi-dimensional process. As such, it can be impaired at multiple stages, producing disorders of empathy with separable underlying causes. Studies often divide empathy into emotional and cognitive components to simplify the large space of empathic processes. This practice can be helpful, but also causes people to misunderstand their interdependence at the level of the mechanism and how they correspond to surveys and tasks. As a result, inferences made from experimental results are often incorrect and cannot be integrated across studies. We explain how emotional and cognitive empathy overlap through the proximate mechanism and clarify their operationalization in common surveys and tasks. A systematic review of three clinical disorders is used to highlight this issue and reinterpret and unite results according to the proximate framework--Borderline Personality Disorder (BPD), Narcissistic Personality Disorder (NPD), and Frontotemporal Dementia (FTD). Aligning constructs through the proximate mechanism allows us to understand both empathy and its disorders.

Investigating the mechanisms of hoarding from an experimental perspective.

BACKGROUND: Acquiring and discarding objects are routine decision processes for most people. Despite the ubiquitous need to make such decisions, little is known about how they are made and what goes wrong when individuals acquire and fail to discard so many items that many areas of their home become unlivable (i.e., clinical hoarding). We hypothesize that clinical hoarding reflects a normal variation in the tendency to acquire and retain objects, only just at a more extreme level. METHODS: To test this hypothesis, we examined 89 nonclinical, undergraduate students' performance on a novel experimental paradigm that measures decisions about acquiring and discarding everyday objects. To test our hypothesis, and validate our task as a possible research tool for studying hoarding, we related decisions on the task to a variety of measures known to correlate with clinical hoarding. The paradigm was sensitive to individual differences, as subjects varied widely in the quantity of objects they chose to acquire and retain under an increasing pressure to discard. In addition, we replicated expected relationships from the clinical hoarding literature between acquisition and retention tendencies and self-report measures of hoarding, indecisiveness, and obsessive-compulsive behavior. RESULTS: Our data suggest that decisions about objects, even in a nonclinical undergraduate population, vary widely and are influenced by the same variables that influence clinical hoarding, but to a less extreme degree. CONCLUSIONS: Future research with this experimental task can separately investigate the role of acquisition, retention, impulsivity, and sensitivity to constraints in clinical hoarding to inform our understanding of this disorder.

A decision theory perspective on why women do or do not decide to have cancer screening: systematic review.

AIM: This paper is a report of a review in which decision theory from economics and psychology was applied to understand why some women with access to care do not seek cancer screening. BACKGROUND: Mammography and cervical smear testing are effective modes of cancer screening, yet many women choose not to be screened. Nurses need to understand the reasons behind women's choices to improve adherence. DATA SOURCES: Research papers published between January 1994 and November 2008 were identified using the Cumulative Index to Nursing and Allied Health Literature, MEDLINE and PsycINFO data bases. The search was performed using the following terms: cervical cancer screening, breast cancer screening, decision, choice, adherence and framing. Forty-seven papers were identified and reviewed for relevance to the search criteria. METHODS: Nineteen papers met the search criteria. For each paper, reasons for obtaining or not obtaining cancer screening were recorded, and organized into four relevant decision theory principles: emotions, Prospect Theory, optimism bias and framing. FINDINGS: All women have fears and uncertainty, but the sources of their fears differ, producing two main decision scenarios. Non-adherence results when women fear medical examinations, providers, tests and procedures, do not have/seek knowledge about risk and frame their current health as the status quo. Adherence is achieved when women fear cancer, but trust care providers, seek knowledge, understand risk and frame routine care as the status quo. CONCLUSION: Nurses need to address proactively women's perceptions and knowledge about screening by openly and uniformly discussing the importance and benefits.

Regulating Emotions during Difficult Multiattribute Decision Making: The Role of Pre-Decisional Coherence Shifting.

Almost all real-life decisions entail attribute conflict; every serious choice alternative is better than its competitors on some attribute dimensions but worse on others. In pre-decisional "coherence shifting," the decision maker gradually softens that conflict psychologically to the point where one alternative is seen as dominant over its competitors, or nearly so. Specifically, weaknesses of the eventually chosen alternative come to be perceived as less severe and less important while its strengths seem more desirable and significant. The research described here demonstrates that difficult multiattribute decision problems are aversive and that pre-decisional coherence shifting aids individuals in regulating that emotional discomfort. Across three studies, attribute conflict was confirmed to be aversive (Study 1), and skin conductance responses and ratings of decision difficulty both decreased in participants who coherence shifted (Study 2). Coherence shifting was also diminished among decision makers who were depleted of regulatory resources, known to be required for common emotion regulation mechanisms. Further, coherence shifting was shown to be relatively common among people who reported strong suppression tendencies in everyday emotion regulation (Study 3). Overall, the data suggest that, at least in part, coherence shifting serves as a tool that helps decision makers manage the pre-decisional discomfort generated by attribute conflict. Theoretical and practical implications are discussed.

Hoarders Only Discount Consumables and Are More Patient for Money.

Individuals with hoarding disorder (HD) excessively acquire and retain goods while also exhibiting characteristics of impulsivity and addiction. However, HD individuals do not always perform impulsively in experiments, they do not appear interested in money, and they exhibit many features of risk-aversion and future-planning. To examine impulsivity in HD, we compared validated community participants high and low in hoarding tendencies on questionnaire measures of hoarding and impulsivity as well as a standard experimental measure of impulsivity (intertemporal discounting) that was modified to compare decisions about money, pens, and snacks. Common discounting effects were replicated. Compared to the low hoarding group, the high hoarding group was more impatient for consumables (pens and snacks) but they were more patient for money. This increased patience for money in high hoarding individuals is in contrast to all other studies on discounting in disordered populations, but consistent with the phenomenology of HD. HD does not appear to be driven by a fundamental inability to wait, but rather a specific, potent desire for consumable rewards.

Cache decision making: the effects of competition on cache decisions in Merriam's kangaroo rat (Dipodomys merriami).

Caching food is an economic, decision-making process that requires animals to take many factors into account, including the risk of pilferage. However, little is known about how food-storing animals determine the risk of pilferage. In this study, the authors examined the effect of a dominant competitor species on the caching and behavior of Merriam's kangaroo rat (Dipodomys merriami). The authors found that, as with conspecific competitors, kangaroo rats did not alter caching in response to the mere presence of a heterospecific competitor, but moved caches to an unpreferred area when the competitor's presence was paired with pilferage. These data suggest that Merriam's kangaroo rat assesses pilfer risk from actual pilferage by a competitor and adaptively alters cache strategy to minimize future risk.

Evidence against mood-congruent attentional bias in Major Depressive Disorder.

Depression is consistently associated with biased retrieval and interpretation of affective stimuli, but evidence for depressive bias in earlier cognitive processing, such as attention, is mixed. In five separate experiments, individuals with depression (three experiments with clinically diagnosed major depression, two experiments with dysphoria measured via the Beck Depression Inventory) completed three tasks designed to elicit depressive biases in attention, including selective attention, attentional switching, and attentional inhibition. Selective attention was measured using a modified emotional Stroop task, while attentional switching and inhibition was examined via an emotional task-switching paradigm and an emotional counter task. Results across five different experiments indicate that individuals with depression perform comparably with healthy controls, providing corroboration that depression is not characterized by biases in attentional processes.