Latest Research News on Neurobiology : Dec 2021
Neurobiology of Depression
Current treatments for depression are inadequate for many individuals, and progress in understanding the neurobiology of depression is slow. Several promising hypotheses of depression and antidepressant action have been formulated recently. These hypotheses are based largely on dysregulation of the hypothalamic-pituitary-adrenal axis and hippocampus and implicate corticotropin-releasing factor, glucocorticoids, brain-derived neurotrophic factor, and CREB. Recent work has looked beyond hippocampus to other brain areas that are also likely involved. For example, nucleus accumbens, amygdala, and certain hypothalamic nuclei are critical in regulating motivation, eating, sleeping, energy level, circadian rhythm, and responses to rewarding and aversive stimuli, which are all abnormal in depressed patients. A neurobiologic understanding of depression also requires identification of the genes that make individuals vulnerable or resistant to the syndrome. These advances will fundamentally improve the treatment and prevention of depression. 
The Neurobiology of Stress and Development
Stress is a part of every life to varying degrees, but individuals differ in their stress vulnerability. Stress is usefully viewed from a biological perspective; accordingly, it involves activation of neurobiological systems that preserve viability through change or allostasis. Although they are necessary for survival, frequent neurobiological stress responses increase the risk of physical and mental health problems, perhaps particularly when experienced during periods of rapid brain development. Recently, advances in noninvasive measurement techniques have resulted in a burgeoning of human developmental stress research. Here we review the anatomy and physiology of stress responding, discuss the relevant animal literature, and briefly outline what is currently known about the psychobiology of stress in human development, the critical role of social regulation of stress neurobiology, and the importance of individual differences as a lens through which to approach questions about stress experiences during development and child outcomes.
Neurobiology of addiction
Addictive drugs have habit-forming actions that can be localized to a variety of brain regions. Recent advances in our understanding of the chemical ‘trigger zones’ in which individual drugs of abuse initiate their habit-forming actions have revealed that such disparate drugs as heroin, cocaine, nicotine, alcohol, phencyclidine, and cannabis activate common reward circuitry in the brain. Although these drugs have many actions that are distinct, their habit-forming actions (and perhaps the relevant elements of their disparate withdrawal symptoms) appear to have a common denominator, namely, similar effects in the brain mechanisms of reward. 
Social Ostracism and Criminality among Medical Waste Workers in Bangladesh: Neurobiological Aspects
Background: Complex relationships exist between socio-economic inequality, social stratification, drug addiction, and criminality in society. A great deal is now known regarding the neurobiology underlying behaviours such as drug addiction and criminality. Most sociological and psychological theories of why such behaviours and phenomena exist have been constructed based on observations made in Western cultures. The unique social, economic, and cultural characteristics of the developing world, and in particular South Asia, have not typically been taken into account. Medical waste workers are a particularly marginalized population in this region, and are uniquely vulnerable to becoming engaged in these behaviours which are harmful to them and to society.
Methods: Here we examine the influence of social inequality and stratification on initiation into criminality, specifically drug use, amongst medical waste operatives, in Dhaka, Bangladesh. Data were collected from a wide range of people (n = 74) involved with medical waste handling through sampling strategy to collect the required data using a variety of qualitative techniques included observation, formal and informal dialogue. Sampling strategies included formal representative sampling, purposive and authoritative sampling.
Results: Data suggests that the compounded effects of social discrimination, fatalistic belief system, socio-economic disparity and finally ostracism may interact with neurobiological predispositions to create unique drug abuse and criminality profiles amongst medical waste workers.
Conclusion: These findings challenge current models of factors contributing to drug use and criminality in society among adolescents and suggest a new framework for conceptualizing these complex issues that incorporates these complex biological, psychological, and sociological factors. 
Evidence for Oxidative Stress in Suicide Cases- A Postmortem Study
Aim: Many researchers have studied the oxidative mechanism and found that its disruption may play a role in the etiopathogenesis of certain psychiatric diseases such as major depression, bipolar disorder, attention deficit and hyperactivity disorders and schizophrenia, all of which have high suicide incidences. We aimed to investigate post-mortem suicide cases to test the hypothesis that the oxidative mechanism is disturbed by suicidal behaviours.
Methods: We performed this study on post-mortem blood samples of 35 suicide cases and 25 control patients with different mortis causa. The total antioxidant status (TAS) and total oxidant status (TOS) of the plasma were measured using a novel automated colorimetric measurement method.
Results: TAS levels were significantly higher in the suicide group compared to the control group. There was no significant difference in the TOS level between the two groups.
Conclusion: TAS is increased in the systemic circulation of people who commit suicide. We believe that TAS and TOS may be used as a diagnostic parameter in the future after further study. Additionally, antioxidant prophylaxis may be used in psychiatric disorders to prevent suicide.
 Nestler, E.J., Barrot, M., DiLeone, R.J., Eisch, A.J., Gold, S.J. and Monteggia, L.M., 2002. Neurobiology of depression. Neuron, 34(1), pp.13-25.
 Gunnar, M. and Quevedo, K., 2007. The neurobiology of stress and development. Annu. Rev. Psychol., 58, pp.145-173.
 Wise, R.A., 1996. Neurobiology of addiction. Current opinion in neurobiology, 6(2), pp.243-251.
 Patwary, M.A., Uddin, L.Q., O’Hare, W.T. and Sarker, M.H., 2014. Social ostracism and criminality among medical waste workers in Bangladesh: Neurobiological aspects. Journal of Scientific Research and Reports, pp.1475-1489.
 Kokacya, M.H., Celikel, A., Copoglu, U.S., Zeren, C., Eren, A., Sahpolat, M. and Ozcan, O., 2016. Evidence for oxidative stress in suicide cases-A postmortem study. International Neuropsychiatric Disease Journal, pp.1-6.