The second-to-fourth digit ratio (2D: 4D) is an indirect, retrospective, non-invasive measure
that correlates negatively with intrauterine exposure to testosterone. The present meta …

Social networks sites have become the most popular instrument used to communicate and
exchange information resulting in the addiction to this media. Previous studies suggested …

Background There is sufficient evidence that the index-finger-to-ring-finger-ratio (2D: 4D-
ratio) is associated with testosterone and estrogen exposure during the fetal stage. More …

Prenatal testosterone is considered to be a possible factor contributing to the development
of attention-deficit/hyperactivity disorder (ADHD) symptomatology, but findings regarding the …

Human studies have reported inconsistent associations between the length ratio of the
second finger to the fourth finger (2D: 4D), which is a proxy for prenatal androgen load, and …

Background Alcohol binge drinking behavior is an important public health issue. Causal
rodent and human associational studies show that reinforcement of prenatal androgen …

Substance use disorder is an important mental health problem with increasing frequency.
This study aims to investigate the 2D: 4D ratio, Dr-I values (right-left differences) …

Objective The ratio of 2nd and 4th digit length (2D4D) is considered to be a sexually
dimorphic trait. Low 2D4D is implicated in alcohol dependence and heroin dependence and …

Background Higher prenatal testosterone exposure regulates brain development and affects
learning and intelligence directly. The digit ratio (2D: 4D) is regarded as an indicator of …

Objective To compare the ratio of the right and left second and fourth digits (2D: 4D),
aggression, and impulsivity levels in opiate use disorder (OUD), alcohol use disorder (AUD) …