A general motivational architecture for human and animal personality

Premises for digital twins reporting on Atlantic salmon wellbeing

Many species of fish, birds and mammals commonly live in human captivity; Atlantic salmon Salmo salar is one of them. The international legal status of the welfare of captive animals is slowly developing and still requires rigorous specification. For example, even though fish have complex cognition and elements of sentience, The United Nations' animal welfare principles still take a functional health-centred perspective overlooking the cognitive-affective component. Wellbeing problems remain a major source of slow growth and high mortality in intensive aquaculture of Atlantic salmon. The value system for decision making in vertebrates is based on expectations of emotional wellbeing for the options available and is linked with the individual's assessment of its future. We propose a new approach for monitoring and improving the welfare of salmon (or any other captive or wild vertebrate) based on modelling the salmon's wellbeing system by digital twins, which are simulation models that implement major bodily mechanisms of the organism. Indeed, predictions on boredom, stress and wellbeing can all be captured by a computational evolutionary model of the factors underlying behaviour. We explain how such an agent-based model of salmon digital twins can be constructed by modelling a salmon's subjective wellbeing experience along with prediction of its near future and allostasis (the bodily preparation for the expected near future). We attempt to identify the building blocks required in digital twin models to deliver early warnings about escalating issues that could eventually lead to negative effects on salmon health in aquaculture. These models would provide critical insights for optimizing production processes and could significantly reduce the reliance on animal experiments. Overall, reports of a population of digital twins could support the implementation of 3Rs - replacement, reduction, refinement - by offering actionable information to fish farmers as well as consumers, voters, politicians and regulators on relevant issues as well as guide experimental work on animal wellbeing across species.

It's bigger on the inside: mapping the black box of motivation

Many motivational constructs are opaque "black boxes," and should be replaced by an explicit account of the underlying psychological mechanisms. The theory of motivational systems has begun to provide such an account. I recently contributed to this tradition with a general architecture of motivation, which connects "energization" and "direction" through the goal-setting activity of emotions, and serves as an evolutionary grounded map of motivational processes.

Sexual fulfilment, wellbeing and risk considerations for people with sexual attractions to children

Research focused on understanding the experiences of individuals with sexual attractions to children and their pursuit of sexual fulfilment faces notable limitations, primarily stemming from ethical and legal challenges, and pervasive social stigma. This review paper explores these challenges and outlines the connections between sexual fulfilment, treatment goals and overall wellbeing. We consider the importance of sexual satisfaction in promoting mental and physical health, and its potential role in reducing the risk of sexually abusive behaviors. Recognizing that promoting healthier and more fulfilling lives extends beyond risk mitigation, the paper highlights future research avenues such as exploring the conceptualization and achievement of sexual satisfaction. In examining alternative perspectives, including the potential risk enhancement associated with achieving sexual fulfilment, we also argue the need for an evidence-based approach and robust research agenda to inform and guide interventions. Through these considerations, the paper aims to encourage a more informed and compassionate understanding of sexual fulfilment for people with sexual attractions to children.

The Alternative Model of Personality Disorders: Assessment, Convergent and Discriminant Validity, and a Look to the Future

The Alternative Model of Personality Disorders (AMPD) is a dimensional, empirically based diagnostic system developed to overcome the serious limitations of traditional categories. We review the mounting evidence on its convergent and discriminant validity, with an incursion into the less-studied ICD-11 system. In the literature, the AMPD's Pathological Trait Model (Criterion B) shows excellent convergence with normal personality traits, and it could be useful as an organizing framework for mental disorders. In contrast, Personality Functioning (Criterion A) cannot be distinguished from personality traits, lacks both discriminant and incremental validity, and has a shaky theoretical background. We offer some suggestions with a view to the future. These include removing Criterion A, using the real-life consequences of traits as indicators of severity, delving into the dynamic mechanisms underlying traits, and furthering the integration of currently disengaged psychological paradigms that can shape a sounder clinical science.

An evolutionary analysis of the applicability and utility of the clinico-pathological method in psychiatry

Unlike other medical specialties, psychiatry has not been involved in the theoretical shift that replaced the syndromal approach with the clinico-pathological method, which consists in explaining clinical manifestations by reference to morbid anatomical and physiological changes. Past and present discussions on the applicability of the clinico-pathological method in psychiatry are based on a pre-Darwinian concept of biology as the study of proximate causation. Distinguishing between mediating mechanisms and evolved functions, an evolutionary perspective offers an original contribution to the debate by overcoming the opposite views of dualism (i.e., the clinico-pathological method is not applicable to disorders of the mind) and neuroessentialism (i.e., the definitive way of explaining psychiatric disorders is by reference to the brain and its activity). An evolutionary perspective offers original insights on the utility of the clinico-pathological method to solve critical questions of psychiatric research and clinical practice, including the distinction between mental health and illness, a better understanding of the etiology and pathophysiology, the classification and differential diagnosis of psychiatric disorders, and the development of more efficacious psychiatric treatments.

Development and Validation of the Interpersonal Motivational Systems Questionnaire (IMS-Q)

Framed within the evolutionary framework, the Interpersonal Motivational System (IMS) theory suggests that eight distinct motivational impulses drive interpersonal human relationships, namely caregiving, social affiliation, attachment, rank-dominance, rank-submission, social play, cooperation, and sexuality. This theory has been widely applied in clinical practice, where psychopathology is viewed as the result of non-flexible or excessive activation of one system over another. Despite its clinical relevance, empirical studies aimed at measuring IMSs are scarce. This paper contributed to filling this gap by proposing a questionnaire to measure individuals' activation of the eight IMSs. Two studies involving large samples of adults were conducted. The first study (N = 455; 76.5% females) concerned the development of the questionnaire and examination of its content validity through explorative factor analysis. In the second study (N = 635; 54.8% females), confirmatory factor analyses were performed to further refine and confirm the instrument's factor structure. The final version consisted of 50 items. Empirical validity was established by investigating the correlations between the eight IMSs and other related measures (i.e., personality traits, human basic values, and attachment dimensions). The findings suggest that the IMS framework can be used to understand individual differences in motivation and behavior in different social contexts.

Associations Between Early Life Adversity, Reproduction-Oriented Life Strategy, and Borderline Personality Disorder

Importance

Borderline personality disorder (BPD) is often accompanied by a history of high-risk sexual behavior and somatic comorbidities. Yet, these features are most often considered in isolation and little is known about their underlying developmental pathways. Life history theory, a leading framework in evolutionary developmental biology, can help make sense of the wide range of behaviors and health issues found in BPD.

Objective

To examine whether the emergence of BPD is associated with the prioritization of immediate reproductive goals over longer-term somatic maintenance goals, a life strategy that can be viewed as a developmental response to adverse early life experiences, providing rapid reproductive benefits despite costs to health and well-being.

Design, Setting, and Participants

This study used cross-sectional data from the second wave of the National Epidemiologic Survey on Alcohol and Related Conditions in 2004-2005 (n = 34 653). Civilian, noninstitutionalized individuals in the US, 18 years or older, and those with and without a DSM-IV diagnosis of BPD were included. Analysis took place between August 2020 and June 2021.

Main Outcomes and Measures

Structural equation models were used to examine whether early life adversity was associated with the likelihood of a BPD diagnosis, either directly or indirectly through a life strategy whereby individuals trade somatic maintenance for immediate reproduction.

Results

Analyses were performed on a sample of 30 149 participants (females: 17 042 [52%]; mean [SE] age, 48.5 [0.09]; males: 12 747 [48%]; mean [SE] age, 47 [0.08]). Of these, 892 (2.7%) had a diagnosis of BPD and 29 257 (97.3%) did not have BPD. Mean early life adversity, metabolic disorder score, and body mass index were significantly higher among participants with a diagnosis of BPD. In an analysis adjusted for age, individuals with BPD reported having significantly more children than those without BPD (b =0.06; SE, 0.01; t = 4.09; P < .001). Having experienced greater levels of adversity in early life was significantly associated with a greater risk of being diagnosed with BPD later in life (direct relative risk = 0.268; SE, 0.067; P < .001). Importantly, this risk was further increased by 56.5% among respondents who prioritized short-term reproductive goals over somatic maintenance (indirect relative risk = 0.565; SE, 0.056; P < .001). Similar patterns of associations were found in male and female individuals.

Conclusions and Relevance

The hypothesis of a reproduction/maintenance life history trade-off mediating the association between early life adversity and BPD helps make sense of the high dimensionality that characterizes the physiological and behavioral correlates of BPD. Additional studies are needed to confirm these results using longitudinal data.

Evolutionary psychiatry: foundations, progress and challenges

Evolutionary biology provides a crucial foundation for medicine and behavioral science that has been missing from psychiatry. Its absence helps to explain slow progress; its advent promises major advances. Instead of offering a new kind of treatment, evolutionary psychiatry provides a scientific foundation useful for all kinds of treatment. It expands the search for causes from mechanistic explanations for disease in some individuals to evolutionary explanations for traits that make all members of a species vulnerable to disease. For instance, capacities for symptoms such as pain, cough, anxiety and low mood are universal because they are useful in certain situations. Failing to recognize the utility of anxiety and low mood is at the root of many problems in psychiatry. Determining if an emotion is normal and if it is useful requires understanding an individual's life situation. Conducting a review of social systems, parallel to the review of systems in the rest of medicine, can help achieve that understanding. Coping with substance abuse is advanced by acknowledging how substances available in modern environments hijack chemically mediated learning mechanisms. Understanding why eating spirals out of control in modern environments is aided by recognizing the motivations for caloric restriction and how it arouses famine protection mechanisms that induce binge eating. Finally, explaining the persistence of alleles that cause serious mental disorders requires evolutionary explanations of why some systems are intrinsically vulnerable to failure. The thrill of finding functions for apparent diseases is evolutionary psychiatry's greatest strength and weakness. Recognizing bad feelings as evolved adaptations corrects psychiatry's pervasive mistake of viewing all symptoms as if they were disease manifestations. However, viewing diseases such as panic disorder, melancholia and schizophrenia as if they are adaptations is an equally serious mistake in evolutionary psychiatry. Progress will come from framing and testing specific hypotheses about why natural selection left us vulnerable to mental disorders. The efforts of many people over many years will be needed before we will know if evolutionary biology can provide a new paradigm for understanding and treating mental disorders.

Status-impact assessment: is accuracy linked with status motivations?

Status hierarchies are ubiquitous across cultures and have been over deep time. Position in hierarchies shows important links with fitness outcomes. Consequently, humans should possess psychological adaptations for navigating the adaptive challenges posed by living in hierarchically organised groups. One hypothesised adaptation functions to assess, track, and store the status impacts of different acts, characteristics and events in order to guide hierarchy navigation. Although this status-impact assessment system is expected to be universal, there are several ways in which differences in assessment accuracy could arise. This variation may link to broader individual difference constructs. In a preregistered study with samples from India (N = 815) and the USA (N = 822), we sought to examine how individual differences in the accuracy of status-impact assessments covary with status motivations and personality. In both countries, greater overall status-impact assessment accuracy was associated with higher status motivations, as well as higher standing on two broad personality constructs: Honesty-Humility and Conscientiousness. These findings help map broad personality constructs onto variation in the functioning of specific cognitive mechanisms and contribute to an evolutionary understanding of individual differences.

The evolution of personality disorders: A review of proposals

Personality disorders (PDs) are currently considered dysfunctions. However, personality differences are older than humanity and are ubiquitous in nature, from insects to higher primates. This suggests that a number of evolutionary mechanisms-other than dysfunctions-may be able to maintain stable behavioral variation in the gene pool. First of all, apparently maladaptive traits may actually improve fitness by enabling better survival or successful mating or reproduction, as exemplified by neuroticism, psychopathy, and narcissism. Furthermore, some PDs may harm important biological goals while facilitating others, or may be globally beneficial or detrimental depending on environmental circumstances or body condition. Alternatively, certain traits may form part of life history strategies: Coordinated suites of morphological, physiological and behavioral characters that optimize fitness through alternative routes and respond to selection as a whole. Still others may be vestigial adaptations that are no longer beneficial in present times. Finally, variation may be adaptative in and by itself, as it reduces competition for finite resources. These and other evolutionary mechanisms are reviewed and illustrated through human and non-human examples. Evolutionary theory is the best-substantiated explanatory framework across the life sciences, and may shed light on the question of why harmful personalities exist at all.