^{Lakshmeesha Bhat}1^{, Subramanya K}2

1^{Department of Psychology, School of Social and Behavioral Sciences, Central University of Karnataka, Gulbarga-585106, Karnataka, India}
2<sup>Department of Electrical & Electronics Engineering, St. Joseph Engineering College, Vamanjoor, Mangalore- 575028, Karnataka, India

Corresponding author:
Subramanya K.
Department of Electrical & Electronics Engineering
St. Joseph Engineering College
Vamanjoor, Mangalore- 575028, India
Phone: +91 9986870096
Fax: +91 824 2263751
E-mail: askbhat@ieee.org


Abstract:
It is with interest that I read the PLoS ONE research article that uses a mathematical model of relationships to understand dynamics and poor marital matching [1]. The mechanisms underlying good marital matching have been the subject of much debate, and no model has clearly explained the processes that govern marital dynamics. We propose an alternative hypothesis that circadian clocks govern good marital matching. The proposed model is based on the projection of the principle of resonance occurring in coupled oscillators having similar natural frequency. We believe that a similar mechanism exists in pair bonding and is the key requirement for good marital matching. It is our inference that the degree of similarity between male and female chronotypes in a pair is favorable to optimal matching. To the best of our knowledge, this is the first report describing a relationship between chronobiology and marital dynamics. This hypothesis contributes what may be an important link to understanding the mechanisms by which anti-marriage attitudes or divorces occur.

Keywords: circadian rhythm, resonance, marital dynamics, matching.

Introduction
When circadian clocks are entrained (synchronized) by periodic signals from their environment (zeitgebergers) their phase relationship to the zeitgeberger cycle is known as chronotype [2]. In this correspondence, we employ an engineering principle of oscillator design to study the influences of close relationship quality of chronotypes of two individuals. Let us turn to the classical theory of oscillation. As it is well known, when two coupled oscillators, say tuning forks, have similar natural frequencies the magnitude of response of the system takes its maximum (resonance) [3]. Here, we propose a hypothesis that the phenomenon of resonance also occurs when two individuals with identical chronotypes synchronize (co-ordinate), and is the basis for circardian oscillator theory of martial matching.

The hypothesis
Marriage is an important social institution, but key aspects of marital dynamics remain poorly understood [4]. Most popular theories of marital choice devised by social scientists employ the concept of economic marketplace and draw a rough analogy between the search for a fitting spouse and the search for suitable goods and services [5]. If this ‘marriage market’ theory governs optimal choice, questions remain. For example, by what mechanisms this might occur? Why does significant proportion of marriages worldwide end up in divorce court? Why “antimarriage” attitude exists until mid-twenties? A paucity of literature exists on the subject of marital matching with the majority of research concentrating on socioeconomic factors. In our opinion, a primary requirement for good marital matching is the toning of male and female chronotypes, and the degree of similarity is conducive to optimal matching.

Discussion
There is little doubt that very early marriages have a poor quality of martial matching [5]. The striking high prevalence of divorce (upto 40%) in those whole married in their early ages (20-25 years) should alarm us. Divorce rates are relatively lower when age at marriage of less than 20 years and more than 25 years [6]. Age is also one of the strongest predictor of “anti-marriage” attitudes. Young adults are more likely embrace “anti-marriage” attitudes than the older ones, the underlying cause(s), however, remain largely unknown [7]. We believe that the changes occurring in chronotypes of males and females in early twenties hold the key to understanding barriers to good marital matching.
Many physiological functions in the body, such as hormonal secretion, maintenance of body temperature, and blood pressure, and sexual activity are related to the circadian rhythm [8, 9]. As children, we are early chronotypes, and become progressively late (delaying) during development, reaching a maximum ‘lateness’ at around the age of 20. After 20 we become earlier again with advancing age. In other words, the mid-sleep on free days (MSF), which determines the chronotype of a person, versus age curve for both genders appear to be like a large inverted ‘U’ with their peak at around 20 years of age. The peak is considered as a marker for the end of adolescence [10]. Also, there exists a physiological difference between the age relationships of male & female chronotypes. Once adolescence is crossed, normally the chronotype of females attains “earliness” sooner than that of males. We believe that the physiological difference between male & female chronotypes explains a commonly observed social phenomenon that the groom is older than the bride. Most couples consist of a younger woman and an older man; most probably because once adolescence is crossed, men generally have their MSF matched with women who are couple of years younger to them. A closer observation of these curves reveal that male in their early adulthood (20-25 years) pass through a distinct phase, wherein their MSF does not match with females of any age-group. It is our conclusion that the lack of optimal matching of chronotypes in early ages leads to development of “anti-marriage” attitudes in them and conversely has a negative impact on the success of marriage of very young couples.

Conclusion
A better understanding of physical systems and the application of the philosophy learnt to our daily life could prove to be a big boon for the mankind. This paper utilizes the physics principle of resonance of oscillators to propose for the first time a relationship between chronobiology and martial matching. We believe that a system of examining compatibility based on chronotypes of the aspirant couple if developed would have a role, at least in part, in good marital matching. However, further investigation is needed to gain a better understanding of the relationship between chronobiology and marital matching and for extending the hypothesis to include close relationships such as friendship between two or more people. If this brief correspondence stimulates scientists to engage in further research in chronobiology and marital dynamics, it will amply serve its purpose.

Conflict of Interest: No Conflict of Interest to be declared.


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