A comprehensive review on stress neurobiology: Physical and psychological stress

Stress is a term used to describe emotionally and physically demanding circumstances. In common jargon, “good stress” pertains to short experiences and leaving a feeling of accomplishment, whereas “bad stress” refers to experiences that lack a degree of stability and are frequently prolonged or emotionally and physically exhausting. The stress system, which combines a wide variety of brain regions that, together, are capable of detecting events and interpreting them as genuine or prospective dangers, is known to construct and initiate the reaction to stressful stimuli.

The blood brain barrier: Its invincible susceptibility

The blood brain barrier (BBB) is a specialized and dynamic network of brain microvascular endothelial cells (BMVEC) that serve critical functions of protecting the brain from harmful substances and supplying nutrients to neural tissue. Its ethereal complexity continues to intrigue scientists, neurologists, neurosurgeons and researchers alike. Due to the brain’s sophisticated system, it becomes prone to a spectrum of neurological disorders and diseases.

Pregnancy turns back the clock

Pregnancy is a complex enough biological process as it is due to the vast number of hormonal fluctuations as the body provides nourishment to the fetus and prepares for labor1. Changes in hormone levels go hand in hand with changes in the anatomy of the brain, such as a reduction in gray matter volume. A study done by Luders and colleagues studied potential age reversal effects in the brain following pregnancy.

A brief introduction to visual snow syndrome 

Visual Snow Syndrome is still a medical mystery due to its rarity and frequent misdiagnosis. Visual Snow Syndrome (VSS) is a neurological disorder characterized by a wide array of visual symptoms. Its defining symptom is the titular visual snow, which involves seeing constant flickers of innumerable tiny dots across the visual field. The observed static is typically black and white, though it might be colorful in other circumstances. The intensity of the static may also vary with ambient luminosity, texture or color of the background. 

Who is you? A look at the intricacies of human behavior and one’s sense of self through the lens of neurotransmitters. 

A general acceptance of how different brain regions are involved in specific processes is a relatively easy concept for one to understand. Despite the underlying mechanisms behind these functions being somewhat unknown, a delegation of tasks within the brain seems efficient and natural. With mapped out paths and effects of certain molecules then it is rational to assume that knowledge could be applied to help remedy common issues within the brain and how chemicals determine human feeling and functions.

The dopamine drive: Mesolimbic reward pathway

Dopamine is a chemical messenger that influences brain pathways that promote motivation and reward-driven behaviour.1 Any object, event or activity can act as a reward if it causes one to learn or feel content.2 The brain’s reward system, or mesolimbic pathway, is the circuitry that modulates dopamine release to translate the value of the reward into actions accordingly.3 First, dopamine-releasing neurons in the ventral tegmental area (A) are activated when one expects to receive a reward.3

Neuroimaging biomarkers of treatment response in anxiety disorders

Anxiety disorders are the most prevalent psychiatric conditions across the human lifespan, with an estimated lifetime prevalence of 31.9%.1,2 They are also the sixth leading cause of disability worldwide.3 Despite the significant functional impairment caused by anxiety disorders, patients are often treated as outpatients and subsequently receive less medical attention and treatment monitoring than patients with less prevalent disorders, but are usually treated as inpatients with consistent monitoring, such as schizophrenia or bipolar disorder.4

Neurological developments in adolescence pose a critical vulnerability to substance abuse

Drug addiction or “dependence” is typically defined by three cognitive criteria: compulsive need to take the drug, reduced control in limiting intake, and a negative affective state during withdrawal.1 The reinforcement/reward model effectively describes the neurobiological mechanisms that drive addictive behaviours. Dopaminergic pathways are central to this model, which include regions of the midbrain such as the substantia nigra, striatum, nucleus accumbens, and the ventral tegmental area.1 Drugs, such as cocaine, will prolong dopamine neurotransmitter activity by preventing its reuptake from neurons in the system. Since dopamine is associated with reward behaviours, this effect reinforces an individual’s motivation to seek out and take the drug.