Correlation between Ratio of Index Finger Length to Ring Finger

Length (2D:4D) and Working Memory Performance

Ananta Yudiarso

, Dian Teres Agung

, Hendrik Gunawan

, and Wan YiMing

Faculty of Psychology Surabaya University, Surabaya, Indonesia

Henan Institute of Science and Technology, China

Keywords: Digit Ratio 2D:4D, Working Memory.

Abstract: Ratio of Index Finger Length to Ring Finger Length (2D:4D) expressed a testosterone exposure during in

prenatal. The masculinize the brain through prenatal testosterone exposure resulted a higher cognitive

functioning. Previous studies shown a positive findings correlation between digit ratio (2D:4D) and

cognitive functioning in gifted student sample. However rarely found study to correlate between the digit

ratio (2D:4D) and working memory. We held a survey research among 22 female university students. To

measure digit ratio, we employed autometric software program. Working memory was tested using

computer-based Wisconsin sorting card test. Our result supported the correlation between digit ratio and

working memory. Our finding implicated testosterone exposure influence working memory functioning.

Mental health problem due to working memory functioning problem may detect and prevent with

testosterone exposure.

1 INTRODUCTION

Various mental health had significant relation to

working memory functioning. Several mental

disorder ADHD, addiction, autism, schizophrenia,

anxiety disorder were related to working memory

functioning. The objective of our research is to

verify the biomarker of working memory

functioning trough a phenotype the ratio of finger

length.

Ratio of Index Finger Length to Ring Finger

Length (2D:4D) expressed a testosterone exposure

during in prenatal. The masculinize the brain

through prenatal testosterone exposure resulted a

higher cognitive functioning. Previous studies

shown a positive findings correlation between digit

ratio (2D:4D) and cognitive functioning (Ackermann

et al., 2012; Austin, Manning, McInroy, & Mathews,

2002; Beaton, Magowan, & Rudling, 2012). Digit

ratio also found this influence in spatial memory

(Bull & Benson, 2006; Bull, Davidson, &

Nordmann, 2010) and academic performance (Hopp,

de Moraes, & Jorge, 2012).

Working memory is limited cognitive system for

temporarily holding information for cognitive

executive function such as decision making. Study

in gifted children shown that gifted had higher digit

ratio than normal control (Durdiaková et al., 2015).

There three reasons to hold this research. First

digit ratio is a consistent biomarker for the

testosterone exposure in many species. However, the

use of 2D:4D as an index of prenatal influence of

testosterone is questioned due to inconsistence

findings the effect of testosterone to cognitive

functions. Testosteron is important hormone for

cognitive process of memory (Cherrier et al., 2007;

Ciocca et al., 2016; Davison et al., 2011; King,

Kurdziel, Meyer, & Lacreuse, 2012). In other hand,

There were inconsistent finding for testosterone

involvement in cognitive process (Alarcón,

Cservenka, Fair, & Nagel, 2014; Carré et al., 2015;

Wakabayashi & Nakazawa, 2010).

Secondly, to the best knowledge of researcher,

rarely found study to correlate between the digit

ratio (2D:4D) and working memory.

Thirdly, the effect of testosterone is gender

specific especially in prefrontal and hippocampal

development (Nguyen et al., 2017). Female had

advantage in testosterone influence (Postma et al.,

2000). However the effect testosterone to memory in

male also significantly found in animal study

(Spritzer et al., 2011). Accordingly, we held this

research.

364

Yudiarso, A., Agung, D., Gunawan, H. and Wan, Y.

Correlation between Ratio of Index Finger Length to Ring Finger Length (2D:4D) and Working Memory Performance.

DOI: 10.5220/0008589503640367

In Proceedings of the 3rd International Conference on Psychology in Health, Educational, Social, and Organizational Settings (ICP-HESOS 2018) - Improving Mental Health and Harmony in

Global Community, pages 364-367

ISBN: 978-989-758-435-0

2 METHOD

The participants of this research were 22 University

student with age 18 to 21 year-old. After participant

filling informed consent, we measure digit ratio and

working memory. We employed autometric software

program for digit ratio measurement using picture of

their hand. Working memory was tested among the

participant using computer-based Wisconsin card

sorting test.

The procedure of data collecting as follows.

First, we make picture of participant finger. The

picture processed in autometric program that

calculated the digit ratio index 2D:4D.

We correlated the ratio 2D4D on left and right

hand and raw score of WCST including total correct,

total error, number of trials, ratio difference true and

false, latency and learning value. Further analysis we

calculated for the curve estimation.

3 RESULT

Table 1: Correlation Score WSCL and Digit ratio 2D4D.

Table 2: Mean of Digit Ration 2D:4D.

Left Righ

D2 D4 2D4D D2 D4 2D4

1107

.818

1135

.318

0.979 1114.4

1175.

227

0.948

Graph 1: Curve Estimation

Curve estimation result shown a fit linier function of

quadratic equation between right hand digit ratio and

learning value WSCL.

Picture 1: Digit Ratio 2D:4D measurement using

Autometric



Left Ratio Right Ratio

P R P

TRUE 0.242 0.139 .379* 0.041

FALSE -0.166 0.23 -.375* 0.043

True-

False 0.217 0.166 .418* 0.027

Trial -0.017 0.470 -0.170 0.225

Ratio

Difference

of True

and False

.712** 0.001 .422* 0.025

Latenc

-0.212 0.171 -0.253 0.127

Learning

value 0.08 0.369 .433* 0.028

Correlation between Ratio of Index Finger Length to Ring Finger Length (2D:4D) and Working Memory Performance

365

4 DISCUSSION

Our result indicated positive finding correlation

between right-hand digit ratio 2D4D and working

memory in female participant. Thus, our finding

supported brain masculinization trough testosterone

exposure can be predicted from digit ratio in female

participant. Digit ratio was stable phenotype for

testosterone exposure that influence

neurodevelopmental prefrontal dan hippocampus for

working memory (Liu, Bai, Xia, & Tian, 2018;

Suzuki et al., 2018; Vijayraghavan, Major, &

Everling, 2018).

Our finding supported practical implication of

using digit ratio to detect working memory

functioning especially at female right-hand finger

length digit ratio (2D4D).

Our result has significant implication for health

psychology to understand the biomarker for working

memory function due to testosterone exposure.

Testosterone exposure may a significant alternative

prevention for mental health problem due to working

memory problem. Two alternatives explanation

testosterone influenced working memory

functioning. First, testosterone exposure may

influence epigenetic process to phenotype in brain

structure involved the working memory functioning.

Secondly, testosterone may influence directly

through neurotransmitter activation (seretoninergic,

dopaminergic, GABAergic) that involved in

working memory functioning.

Further research can be focused in mechanism of

testosterone exposure to the central nervous system

that support working memory functioning and

epigenetic process of working memory.

5 CONCLUSION

Our finding supported practical implication of the

use of digit ratio 2D:4D for biomarker in executive

cognitive function. Due to limitation of this

preliminary study a replication study with larger

sample size and broader population with different

genetic background is needed in order to improve

external validation of the result.

REFERENCES

Ackermann, S., Spalek, K., Rasch, Björn, G., Leo,

C., David, F., Matthias, Q., Dominique J. F.

2012. Testosterone levels in healthy men are

related to amygdala reactivity and memory

performance. Psychoneuroendocrinology, 37(9),

1417-1424.

Alarcón, G., Cservenka, A., Fair, Damien A., &

Nagel, BJ. 2014 Sex differences in the neural

substrates of spatial working memory during

adolescence are not mediated by endogenous

testosterone. Brain Research, 1593, 40-54.

Austin, EJ., Manning, JT., McInroy, K., & Mathews,

E. 2002. A preliminary investigation of the

associations between personality, cognitive

ability and digit ratio. Personality and Individual

Differences, 33(7)

Beaton, AA., Magowan, SV., & Rudling, NG. 2012.

Does handedness or digit ratio (2D:4D) predict

lateralised cognitive ability? Personality and

Individual Differences, 52(5), 627-631.

Bull, R., & Benson, PJ. 2006. Digit ratio (2D:4D)

and the spatial representation of magnitude.

Hormones and Behavior, 50(2), 194-199.

Bull, R., Davidson, WA., & Nordmann,. 2010.

Prenatal testosterone, visual-spatial memory, and

numerical skills in young children. Learning and

Individual Differences, 20(3), 246-250.

Carré, JM., Ortiz, TL., Labine, B., Moreau, B.J.P.,

Viding, E., Neumann, C.S., & Goldfarb, B. 2015.

Digit ratio (2D:4D) and psychopathic traits

moderate the effect of exogenous testosterone on

socio-cognitive processes in men.

Psychoneuroendocrinology, 62, 319-326.

Cherrier, M. M., Matsumoto, A. M., Amory, J. K.,

Johnson, M., Craft, S., Peskind, E. R., &

Raskind, M. A. 2007. Characterization of verbal

and spatial memory changes from moderate to

Table: 3 Parameter for Curve estimation.

R Square F df1 df2 Sig. Constant

Linea

0.188 4.163 1 18 0.056 -156.574 152.865

Quadratic 0.481 7.886 2 17 0.004 -3155.024 6548.839 -3403.883

ICP-HESOS 2018 - International Conference on Psychology in Health, Educational, Social, and Organizational Settings

366

supraphysiological increases in serum

testosterone in healthy older men.

Psychoneuroendocrinology, 32(1), 72-79.

Ciocca, G., Limoncin, E., Carosa, E., Di Sante, S.,

Gravina, G.L., Mollaioli, D., Jannini, E.A. 2016.

Is Testosterone a Food for the Brain? Sexual

Medicine Reviews, 4(1), 15-25.

Davison, SL., Bell, RJ., Gavrilescu, M., Searle, K.,

Maruff, P., Gogos, A., Davis, S.R. 2011.

Testosterone improves verbal learning and

memory in postmenopausal women: Results

from a pilot study. Maturitas, 70(3), 307-311.

Durdiaková, J., Celec, P., Laznibatová, J., Minárik,

G., Lakatošová, S., Kubranská, A., &

Ostatníková, D. 2015. Differences in salivary

testosterone, digit ratio and empathy between

intellectually gifted and control boys.

Intelligence, 48, 76-84.

Hopp, R.N., de Moraes, J. P., & Jorge, J. 2012. Digit

ratio and academic performance in dentistry

students. Personality and Individual Differences,

52(5), 643-646.

King, HM., Kurdziel, LB., Meyer, JS., & Lacreuse,

A. 2012. Effects of testosterone on attention and

memory for emotional stimuli in male rhesus

monkeys. Psychoneuroendocrinology, 37(3),

396-409.

Liu, T., Bai, W., Xia, M., & Tian, X. 2018.

Directional hippocampal-prefrontal interactions

during working memory. Behavioural Brain

Research, 338, 1-8.

Nguyen, T., Lew, J., Albaugh, MD., Botteron, KN.,

Hudziak, JJ., Fonov, VS., McCracken, JT. 2017.

Sex-specific associations of testosterone with

prefrontal-hippocampal development and

executive function, Psychoneuroendocrinology,

76, 206-217.

Postma, A., Meyer, G., Tuiten, A., van Honk, J.,

Kessels, R.P.C., & Thijssen, J. 2000. Effects of

testosterone administration on selective aspects

of object-location memory in healthy young

women. Psychoneuroendocrinology, 25(6), 563-

575.

Spritzer, MD., Daviau, ED., Coneeny, MK.,

Engelman, S M., Prince, W.T., & Rodriguez-

Wisdom, KN. 2011. Effects of testosterone on

spatial learning and memory in adult male rats.

Hormones and Behavior, 59(4), 484-496.

Suzuki, K., Kita, Y., Oi, Y., Okumura, Y., Okuzumi,

H., & Inagaki, M. 2018. Right prefrontal cortex

specialization for visuospatial working memory

and developmental alterations in prefrontal

cortex recruitment in school-age children.

Clinical Neurophysiology, 129(4), 759-765.

Vijayraghavan, S., Major, A.J., & Everling, S. 2018.

Muscarinic M1 Receptor Overstimulation

Disrupts Working Memory Activity for Rules in

Primate Prefrontal Cortex. Neuron, 98(6), 1256-

1268.

Wakabayashi, A., & Nakazawa, Y. 2010. On

relationships between digit ratio (2D:4D) and

two fundamental cognitive drives, empathizing

and systemizing, in Japanese sample. Personality

and Individual Differences, 49(8), 928-931.

Correlation between Ratio of Index Finger Length to Ring Finger Length (2D:4D) and Working Memory Performance

367