neuroscience - neural development

endoderm

will eventually develop into the viscera (the organs of the body)

mesoderm

will eventually develop into the bones and muscles

ectoderm

will eventually develop into the nervous system and the skin

neuralation

the formulation of the neuronal tube, where the middle of the neuronal plates fold first, followed by the anterior and posterior ends. the CNS will develop from the walls of the neural tube, and the hollow lumen of the tube will become the ventricles and the spinal canal within the CNS

neural tube defects

occurs when there is a problem in the process of neuralation and the formation/closure of the spinal tube

spina bifida

when the neuronal tube fails to close completely, and as a result the backbone that typically protects the spinal cord also does not form appropriately

anencephaly

caused by the failure of the anterior portion of the neural tube to close, preventing the development of the anterior portion of the brain and associated skull

three vesicle stages of development

prosencephalon (forebrain), telencephalon (midbrain), and rhombencephalon

prosencephalon

eventually develops into the “higher” order brain regions, including the cerebral cortex — made up of the telencephalon and diencephalon

telencephalon

part of the prosencephalon that eventually becomes the cerebral cortex and basal ganglia. It is the most evolved structure of the human brain and is responsible for higher order thinking; processes such as attention, memory, and body language

diencephalon

part of the prosencephalon that eventually forms the thalamus and hypothamamus. In charge of sensory information relaying as well as controlling autonomic functions through the endocrine system

mesencephalon

eventually forms the “midbrain” structures — tectum, and tegmentum

tectum

dorsal portion of the brain that contains two major structures: the superior colliculus and the inferior colliculus

superior colliculus

part of the tectum that is responsible for reflexive eye movement, which allows to quickly orient something changing in the environment

inferior colliculus

part of the tectum responsible for relaying auditory info. to the thalamus for auditory function

tegmentum

ventral portion of the midbrain that contains many parts with many functions, including reward and motivation:

• periaqueductal gray: allows us to respond to painful stimuli

• red nucleus and substantia nigra: coordinate complex movements

• ventral tegmental area: important for the processing of reward and motivation

rhomencephalon

the more rostral portion differentiates into two structures, the cerebellum and the pons

• cerebellum: “little brain;” a structure that enables motor control functions, such as balance, coordination, posture, and learning physical actions

• pons: relays impulses between the motor cortex and the cerebellum; helps us perform involuntary functions like breathing