Brain plasticity in Mothers- a serious effect on Personality and Behaviour?

Behavior is the way a person reacts. It is what an individual does to cause something to happen, change, or retain the same. Behavior is said to be the response to internal stimuli such as thoughts and feelings or to external stimuli such as the environment and people (NSW Government, 2020).

Behavior can be classified as Adaptive, Non-adaptive and Maladaptive based on their effects on survival of an individual in an environment:

-Adaptive behaviors are learnt actions that demonstrate a person's social and practical ability to deal with the demands of daily life (AAID, 2022). Adaptive behaviors are composed of conceptual, social and practical skills that positively enhance survival.

-Non-adaptive behavior is said to be neutral and have no positive or negative effects on survival of the individual.

?-Maladaptive behavior is defined as behavior that interferes with one’s activities of daily living or ability to adjust to and participate in particular environment. These behaviors risk the survival chances of the individual.

In 2002, a group of researchers quantitatively evaluated changes in the maternal brain during and after healthy pregnancy. The conclusion of the study was that, during pregnancy, the brain gradually decreases in size, and after delivery, it grows. The changes occur over a specific period of time in every woman (Oatridge A, Holdcroft A, Saeed N, et al, 2002). Research on animals indicates that reproductive hormone changes are linked to neuronal plasticity in the maternal brain during pregnancy (Leuner, Glasper, & Gould, 2010). The significant changes in brain structure during pregnancy, most notably decreases in the volume of gray matter (GM) in areas supporting social cognition. The observed volume reductions are largely found in association regions of the cerebral cortex rather than being dispersed randomly throughout the brain. It is well known that the affected regions play a significant part in social processes, despite the fact that these higher order regions contribute to a variety of functions. Pregnant women have increased brain response to dangers together with increased psychological awareness to threats and socially restructure their behavior as to enhance life expectancy of the baby. This adaptive behavior is coupled with the reductive brain plasticity or fine tuning of the brain to safeguard the expected infant from the unknown world.

Additional study using structural MRI indicates that the human maternal brain grows structurally during the postpartum period and goes on to say that this growth may be particularly notable in areas of the brain crucial for parenting (Kim, Leckman, Mayes, Feldman, et al., 2010). When the structural imaging of mothers' brains between the first and third months after giving birth were paralleled, numerous large brain areas involved in maternal motivation and reward processing demonstrated an improvement in gray matter. Kim et al. (2010) stated that there might indeed be a link between pregnancy-related GMV (gray matter volume) reduction and the quality of mother–child attachment. It is suggested that the postpartum increase/restoration of GMV is likely associated with a mother’s positive perception of her child, which is in line with the findings in animal studies such as in female mice, nursing and pregnancy promote significant, albeit temporary, grey matter concentration hypertrophy in critical areas related to emotion, motivation, reward, and mnestic processes (Barrière et al. 2021).

Abbe Macbeth, a neuroscientist with Noldus Information Technology, a behavioral research consultancy in Leesburg, Virginia says that less can be more when the brain restructures itself to respond to life changes (Science | AAAS, n.d.). Various studies revealed the brain reconstructed itself only while striving to give the new born efficient care and attention. MRI scans compared brain plasticity of mothers, adoptive mothers and those who had miscarriages only to see significant change in brain structure of mothers’ pre and postpartum while no changes in that of adoptive mothers and no reconstructed GMV in mothers who lost their infants. The brain plasticity is simply non-adaptive to the development of the mother herself.

This indicates the brain plasticity in response to postpartum being increase in size is a structural adaption or maternal adaptive behavior to aid secure growth and development of the next generation in an unsafe and hostile world where the primary care giver is the mother according to social norms and practices while the father or other members focus on fulfilling material needs. Now owing to environmental changes, physical and social, the primary care-givers of a new born can be the biological parents, grandparents, adoptive parents or hired nannies. Even the basic practice of breast-feeding has been substituted by bottle-feeding due to working needs of a busy mother. The new world demands the mother to stay away from her infant to provide basic essentials other than the biological ones, triggered due to the inflation.

The distance and lack of communication between the new born and mother mimics a scenario of the mother having lost her infant and not delivering the parental functions the brain prepared to serve. The adaptive behavior of changes in brain structure now gives a maladaptive effect on the social cognition and memory of the mother out in her work space. The fine tuning of the brain that occurred to facilitate better parental actions becomes maladaptive to mothers trying to focus on career oriented or worldly interests while the care-giver’s role is substituted for. Studies have found that working mothers have cognitive overloads that increase their risk of being predisposed to disorders such as Postpartum Depression, Postpartum Anxiety, or different psychological or physiological disorders.

Other than having a not so intimate relationship or direct connection with the mother, the child can survive with all its needs met in a safe horizon in today’s changing environment. While this lifts the stress off from the mother, as care giving is no more her sole responsibility, the brain structure adaption needs to advance with the evolutionary trends to nullify it being a predisposing factor of mental illnesses in mothers. Further research and study is required to verify or quantify this theory or assumption while also figuring out a management method.

References

Chechko N, Dukart J, Tchaikovski S, et al. The expectant brain-pregnancy leads to changes in brain morphology in the early postpartum period. Cerebral Cortex (New York, N.Y.: 1991). 2022 Sep;32(18):4025-4038. DOI: 10.1093/cercor/bhab463?PMID: 34942007; PMCID: PMC9476604.

Hoekzema, E., Barba-Müller, E., Pozzobon, C., Picado, M., Lucco, F., García-García, D., Soliva, J. C., Tobe?a, A., Desco, M., Crone, E. A., Ballesteros, A., Carmona, S., & Vilarroya, O. (2017). Pregnancy leads to long-lasting changes in human brain structure.?Nature neuroscience,?20(2), 287–296. https://doi.org/10.1038/nn.4458

Kim P. (2016). Human Maternal Brain Plasticity: Adaptation to Parenting.?New directions for child and adolescent development,?2016(153), 47–58. https://doi.org/10.1002/cad.20168

Oatridge, A., Holdcroft, A., Saeed, N., Hajnal, J. V., Puri, B. K., Fusi, L., & Bydder, G. M. (2002). Change in brain size during and after pregnancy: study in healthy women and women with preeclampsia.?AJNR. American journal of neuroradiology,?23(1), 19–26.

Science | AAAS. (n.d.). AAAS. Retrieved November 24, 2022, from https://www.science.org/content/article/pregnancy-resculpts-women-s-brains-least-2-years

What is behaviour? - Principles for effective support. (2020, January 20). What Is Behaviour? - Principles for Effective Support. Retrieved November 24, 2022, from https://www.health.nsw.gov.au/mentalhealth/psychosocial/principles/Pages/behaviour-whatis.aspx#:~:text=Behaviour%20is%20how%20someone%20acts,the%20environment%2C%20including%20other%20people.