Civil Rights
Movements, leaders, victories and the continuing fight for equality.
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Explore the people, places, events, achievements, struggles and stories that shaped our journey.
Movements, leaders, victories and the continuing fight for equality.
Innovation, patents, science, technology and world-changing contributions.
Pioneers, champions, Negro Leagues, records, activism and excellence.
Meet the people whose lives, choices and achievements shaped the journey.
Black towns, communities, institutions and places where history happened.
Moments that changed communities, movements, institutions and the nation.
In 1968 Shirley Chisholm became the first Black woman elected to the United States Congress. In 1972 she launched a campaign for the Democratic presidential nomination, breaking another political barrier.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
These are timelines of brain development events in different animal species.
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These are timelines of brain development events in different animal species. Mouse brain development timeline Macaque brain development timeline Human brain development timeline
The human brain development timeline encompasses the sequential, overlapping phases in which the central nervous system forms, matures, and reorganizes from conception through adolescence and into early adulthood. This process starts in the third gestational week with the differentiation of neural progenitor cells and progresses through neurogenesis, cell migration, synaptogenesis, myelination, and synaptic pruning. Many foundational structures of the brain, including the forebrain, midbrain, and hindbrain, emerge by the sixth week of gestation, with further differentiation resulting in secondary regions like the telencephalon, diencephalon, and metencephalon in subsequent weeks. Structural milestones, including the formation of cortical folds and the appearance of commissural fibers, occur rapidly during prenatal development. Postnatally, white matter volume and grey matter architecture undergo significant changes, with cortical regions maturing at different rates. The frontal and parietal lobes tend to mature earlier than temporal regions, with synaptic pruning and myelination continuing into the fourth decade of life. Experience and environmental factors dynamically shape neural connectivity, influencing lifelong cognitive, affective, and behavioral outcomes. Advances in magnetic resonance imaging and the study of brain organoids have enhanced understanding of neurological disorders and critical periods of vulnerability, enabling new approaches for early diagnosis and intervention.
The house mouse (Mus musculus) has a gestation period of 19 to 21 days. Key events in mouse brain development occur both before and after birth, beginning with peak neurogenesis of the cranial motor nuclei 9 days after conception, up to eye opening which occurs after birth and about 30 days after conception.
Exposure to nicotine, from conventional or electronic cigarettes during adolescence can impair the developing human brain. E-cigarette use is recognized as a substantial threat to adolescent behavioral health. The use of tobacco products, no matter what type, is almost always started and established during adolescence when the developing brain is most vulnerable to nicotine addiction. Young people's brains build synapses faster than adult brains. Because addiction is a form of learning, adolescents can get addicted more easily than adults. The nicotine in e-cigarettes can also prime the adolescent brain for addiction to other drugs such as cocaine. Exposure to nicotine and its great risk of developing an addiction, are areas of significant concern. Nicotine is a parasympathomimetic stimulant that binds to and activates nicotinic acetylcholine receptors in the brain, which subsequently causes the release of dopamine and other neurotransmitters, such as norepinephrine, acetylcholine, serotonin, gamma-aminobutyric acid, glutamate and endorphins. Nicotine interferes with the blood–brain barrier function, and as a consequence raises the risk of brain edema and neuroinflammation. Another under-studied brain-health marker is cerebral blood flow: a study of adolescents reported that the effects of nicotine and tobacco products on brain-health markers during this neurodevelopmental period remain largely unknown and examined associations with decline in cerebral blood flow in the anterior cingulate cortex (ACC) and precuneus/posterior cingulate cortex (PCC). When nicotine enters the brain it stimulates, among other activities, the midbrain dopaminergic neurons situated in the ventral tegmental area and pars compacta. Nicotine negatively affects the prefrontal cortex of the developing brain. Prenatal nicotine exposure can result in long-term adverse effects to the developing brain. Prenatal nicotine exposure has been associated with dysregulation of catecholaminergic, serotonergic, and other neurotransmitter systems. E-liquid exposure whether intentional or unintentional from ingestion, eye contact, or skin contact can cause adverse effects such as seizures and anoxic brain trauma. A study on the offspring of the pregnant mice, which were exposed to nicotine-containing e-liquid, showed significant behavioral alterations. This indicated that exposure to e-cigarette components in a susceptible time period of brain development could induce persistent behavioral changes.
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →Shirley Chisholm, elected in 1968.
