Brain Development

Flashcards covering key concepts related to brain development, including its stages, processes, associated disorders, and clinical features of conditions like autism and Rett syndrome.

What are the three main parts of human brain development?

Forebrain, midbrain, and hindbrain.

Which part of the brain becomes the largest, featuring two cerebral hemispheres and a wrinkled cortex?

The forebrain.

In the cerebral cortex, what is a ridge called, and what is a groove called?

A ridge is a gyrus, and a groove is a sulcus.

What are the six stages of Central Nervous System (CNS) development?

Neurogenesis, Migration, Differentiation, Synaptogenesis, Neuronal cell death, and Synaptic refinement.

What three layers does the Central Nervous System (CNS) begin as before rolling into a tube?

Ectoderm, Mesoderm, and Endoderm.

What cellular process produces neurons and glial cells in the ventricular zone during neurogenesis, and what condition can result from its failure?

Mitosis; failure can result in microcephaly.

What are some brain malformations that can result from disorders of cell migration?

Pachygyria (thick gyrus) or a double-band cortex where cells stop halfway.

How are axons guided to their targets during development?

By chemicals (chemoattractants and chemorepellants) released by target cells, interacting with growth cones equipped with filopodia and lamellipodia.

Which protein is released by the notochord to induce nearby cells in the spinal cord to become motoneurons?

Sonic hedgehog protein.

What are the two main phases of synaptogenesis in brain development?

Synapse Formation (fetal, infancy, childhood) and Synapse Refinement & Elimination (puberty, adolescence, early adulthood).

What molecule initiates apoptosis in neurons by causing mitochondria to release Diablo?

Calcium (Ca++) influx.

For what two essential elements do neurons compete to survive during development?

Neurotrophic factors (chemicals made by target cells) and synaptic connections.

Which genetic disorder is characterized by abnormal dendritic morphology and pruning due to the absence of FMRP?

Fragile X syndrome.

What is the primary role of neurotrophic factors like NGF and BDNF in brain development?

They promote neuron survival, aid regrowth after injury, and regulate synapse selection and cell death.

What is a 'sensitive period of development' in neuroscience?

A specific time when experience makes permanent alterations in brain structure or function.

What is amblyopia and what causes it in early development?

Vision loss in one eye caused by early impairment, often due to misalignment of the eyes and competition of axons from each eye for synaptic targets.

What are some key communication and social interaction impairments seen in individuals with Autism Spectrum Disorder?

Delayed language, echolalia, impaired nonverbal behavior, failure to share enjoyment with others, and poor eye contact.

How is the local connectivity described in autistic brains compared to normal brains?

Autistic brains are hyperconnected locally, often showing abnormal dendritic spines.

What are the key characteristics of Rett syndrome, an X-linked progressive autism spectrum disorder?

Initially normal development followed by loss of purposeful hand use and spoken language, and development of gait abnormalities and hand posturing.