On human self-domestication, psychiatry, and eugenics

The hypothesis that anatomically modern homo sapiens could have undergone changes akin to those observed in domesticated animals has been contemplated in the biological sciences for at least 150 years. The idea had already plagued philosophers such as Rousseau, who considered the civilisation of man as going against human nature, and eventually "sparked over" to the medical sciences in the late 19th and early 20th century. At that time, human "self-domestication" appealed to psychiatry, because it served as a causal explanation for the alleged degeneration of the "erbgut" (genetic material) of entire populations and the presumed increase of mental disorders

No evidence for altered prenatal exposure to testosterone in young females diagnosed with Borderline Personality Disorder

Introduction. Borderline Personality Disorder (BPD) is characterised, among other features, by in- creased impulsivity and aggression, both directed toward the self and others. These clinical signs most likely arise from complex gene-environment interactions. In our study, we sought to elucidate the role of prenatal testosterone exposure in female patients with BPD. Materials and Methods. In a sample of 42 patients and 50 controls matched for age and biological sex, we measured the ratio of the second to the fourth digit of both hands (2D:4D ratio), which is established as a reliable correlate of prenatal testosterone levels in the foetus. In addition, we used sev- eral self-rating scales to determine personality dimensions, impulsivity, aggressiveness and risk-taking behaviour. Results. No differences between the groups emerged with regard to 2D:4D ratio of both hands. In ad- dition, there were almost no correlations between psychological measures and the 2D:4D ratio in the entire sample. Conclusions. Contrary to predictions, female patients with BPD did not differ from controls in 2D:4D ratio bimanually, suggesting no abnormal intrauterine (prenatal) exposure to testosterone in this clinical group. As expected, differences between patients and controls in personality traits, impul- sivity, aggressiveness and risk-taking were highly significant and in concordance with the existing body of knowledge. Since BPD features are highly heterogeneous, it could be interesting to study subgroups of BPD patients, rather than the broader phenotype according to DSM-5 criteria

No evidence for altered prenatal exposure to testosterone in young females diagnosed with Borderline Personality Disorder

Introduction. Borderline Personality Disorder (BPD) is characterised, among other features, by in- creased impulsivity and aggression, both directed toward the self and others. These clinical signs most likely arise from complex gene-environment interactions. In our study, we sought to elucidate the role of prenatal testosterone exposure in female patients with BPD. Materials and Methods. In a sample of 42 patients and 50 controls matched for age and biological sex, we measured the ratio of the second to the fourth digit of both hands (2D:4D ratio), which is established as a reliable correlate of prenatal testosterone levels in the foetus. In addition, we used sev- eral self-rating scales to determine personality dimensions, impulsivity, aggressiveness and risk-taking behaviour. Results. No differences between the groups emerged with regard to 2D:4D ratio of both hands. In ad- dition, there were almost no correlations between psychological measures and the 2D:4D ratio in the entire sample. Conclusions. Contrary to predictions, female patients with BPD did not differ from controls in 2D:4D ratio bimanually, suggesting no abnormal intrauterine (prenatal) exposure to testosterone in this clinical group. As expected, differences between patients and controls in personality traits, impul- sivity, aggressiveness and risk-taking were highly significant and in concordance with the existing body of knowledge. Since BPD features are highly heterogeneous, it could be interesting to study subgroups of BPD patients, rather than the broader phenotype according to DSM-5 criteria

Proximity Induced Superconductivity in CdTe-HgTe Core-Shell Nanowires

In this letter we report on proximity superconductivity induced in CdTe-HgTe core-shell nanowires, a quasi-one-dimensional heterostructure of the topological insulator HgTe. We demonstrate a Josephson supercurrent in our nanowires contacted with superconducting Al leads. The observation of a sizable $I_c R_n$ product, a positive excess current and multiple Andreev reflections up to fourth order further indicate a high interface quality of the junctions.Comment: Accepted for publication in Nano Letter

Testing the unsolved problems hypothesis:The evolutionary life issues-mitigating function of nature exposure and its relationship with human well-being

Theories regarding the benefits of spending time in natural settings – a growingly crucial topic in a progressively urbanized world – have been developed with varying success, and none could comprehensively illuminate the evolutionary underpinnings of this phenomenon. This paper posits that the alleviation of unsolved life problems by means of unique personal (imaginativeness) and environmental (nature exposure) factors and their synthesis, so as to free up opportunities for other evolutionarily-essential tasks in humans, is posited to be pivotal – the unsolved problems hypothesis. Six hundred participants completed a study testing these assumptions on Amazon's Mechanical Turk. Results highlight the relevance of unsolved existential issues in relation to environmental (but not personal or integrative) influences on the majority of well-being indicators (e.g., extent of psychotic symptoms, annual income and procreative outcomes). Findings could initiate new lines of enquiry to unravel the evolutionary mechanism underlying a phenomenon that has huge implications for human functioning and well-being.Nanyang Technological UniversityAccepted versionThis research was funded by Singapore's Nanyang Technological University’s NAP-SUG scheme [NAP SUG2015 (GE)] that was awarded to the last author. The sponsor has no involvement in the study design; collection/analysis/interpretation of data; writing of the report; and in the decision to submit the article for publication