Research suggests that the ratio of the lengths of the index finger and the ring finger in males may be predictive of a variety of disorders related to disturbed hormonal balance. When the index finger is shorter than the ring finger, this results in a small 2D:4D ratio, pointing to a high exposure to testosterone in the uterus.
In a new study of 103 male patients diagnosed with schizophrenia and 100 matched healthy male individuals, investigators found that the 2D:4D ratio may be an effective predictor of schizophrenia–there were significant differences between schizophrenia and control groups concerning the ratio of the lengths of the second digit to the fourth digit, as well as its asymmetry, in both hands.
“Asymmetry index showed moderate discriminatory power and, therefore asymmetry index has a potential utility as a diagnostic test in determining the presence of schizophrenia,” said Dr. Taner Oznur, co-author of the Clinical Anatomy study.
And what are the differences? the article is very brief and does not seem to explain beyond what the normal ratio is… is it greater than the 2/4 they talk about, is the index longer or much shorter?
Anyways, my index on left hand is slightly longer than my ring, close enough to appear same length…can’t count my right since the hand was broken and my ring is noticeably shorter.
The 2D:4D AI (t = 8.723, P < 0.001) was lower in the schizophrenia group than the control group. There was no difference between the schizophrenia and the healthy control groups in respect of height (t = 1.566, P = 0.119) or age (t = 1.184, P = 0.238). The right 2D was longer in the schizophrenia group than the control group (t = 5.821, P < 0.001) but the opposite was the case for the left 2D (t = 1.582, P = 0.115). Both left 4th digit (L4D) (t = 5.56, P < 0.001) and right 4th digit (R4D) (t = 4.109, P < 0.001) were longer in the schizophrenia group than the control group. The left 2nd digit (L2D):4D ratio was higher in the schizophrenia group (t = 6.029, P < 0.001) but the R2D:4D ratio was lower (t = 2.385, P = 0.018) (Table 1) (Fig.2)