A study of second to fourth digit ratio in relation to verbal and numerical intelligence among medical students

Introduction and Aim: Prenatal androgens are believed to be one of the probable etiological factors influencing intellectual development of an individual. In-utero testosterone exposure has been thought to affect the digit ratio which is the ratio of lengths of index finger and ring finger (2D:4D). In the present work we intended to study the correlation of 2D:4D with numerical and verbal intelligence believed to be variable among genders. The aim of our study was to find the association of 2D:4D with Verbal Intelligence and Numerical Intelligence in a sample of medical students. Materials and Methods: This study was conducted in a sample of medical students. 44 female and 44 male students participated in the study. 2D:4D measurements were made using standard procedure after which the participants completed a questionnaire containing 20 questions each to test numerical and verbal intelligence. Results: In this study, Males were found to have a lower 2D:4D when compared to females. Individuals with lower 2D:4D in their right-hand were seen to have lower verbal intelligence and higher numerical intelligence thus suggesting that males are born with better numerical intelligence and females with greater verbal intelligence. Conclusion: Digit ratio can be considered as a valuable indicator of individual differences in terms of intelligence, although the exact role of testosterone on brain to cause variation in these cognitive domains is yet to be clearly understood.