Chapter 8 Flashcards
neural plate
Primitive neural tissue that gives rise to the neural tube.
neural tube
Structure in the early stage of brain development from which the brain and spinal cord develop.
Zygote
Fertilization to 2 weeks
Embryo
2 to 8 weeks
Fetus
9 weeks to birth
neural stem cell
Self-renewing multipotential cell that gives rise to any of the different types of neurons and glia in the nervous system.
subventricular zone
Lining of neural stem cells surrounding the ventricles in adults.
progenitor cell (precursor cell)
Derived from a stem cell; it migrates and produces a neuron or a glial cell.
neuroblast
Product of a progenitor cell that gives rise to any of the different types of neurons.
glioblast
Product of a progenitor cell that gives rise to different types of glial cells.
neurotrophic factor
A chemical compound that supports growth and differentiation in developing neurons and may act to keep certain neurons alive in adulthood.
Stages of Development
- Cell birth (neurogenesis; gliogenesis)
- Cell migration
- Cell differentiation
- Cell maturation (dendrite and axon growth)
- Synaptogenesis (formation of synapses)
- Cell death and synaptic pruning
- Myelogenesis (formation of myelin)
radial glial cell
Path-making cell that a migrating neuron follows to its appropriate destination.
autism spectrum disorder (ASD)
Range of cognitive symptoms from mild to severe that characterize autism; severe symptoms include greatly impaired social interaction, a bizarre and narrow range of interests, marked abnormalities in language and communication, and fixed, repetitive movements.
growth cone
Growing tip of an axon.
filopod (pl. filopodia)
Process at the end of a developing axon that reaches out to search for a potential target or to sample the intercellular environment.
cell adhesion molecule (CAM)
A chemical molecule to which specific cells can adhere, thus aiding in migration.
tropic molecule
Signaling molecule that attracts or repels growth cones.
netrin
Member of the only class of tropic molecules yet isolated.
neural Darwinism
Hypothesis that the processes of cell death and synaptic pruning are, like natural selection in species, the outcome of competition among neurons for connections and metabolic resources in a neural environment.
apoptosis
Genetically programmed cell death.
dorsolateral prefrontal cortex (DLPFC)
Brodmann areas 9 and 46; makes reciprocal connections with posterior parietal cortex and the superior temporal sulcus; responsible for selecting behavior and movement with respect to temporal memory.
growth spurt
Sporadic period of sudden growth that lasts for a finite time.
chemoaffinity hypothesis
Proposal that neurons or their axons and dendrites are drawn toward a signaling chemical that indicates the correct pathway.
amblyopia
Condition in which vision in one eye is reduced as a result of disuse; usually caused by a failure of the two eyes to look in the same direction.
critical period
Developmental window during which some event has a long-lasting influence on the brain; also, sensitive period.
imprinting
Formation of an attachment by an animal to one or more objects or animals at a critical period in development.
testosterone
Sex hormone secreted by the testes and responsible for the distinguishing characteristics of the male.
androgen
Class of hormones that stimulates or controls masculine characteristics.
masculinization
Process by which exposure to androgens (male sex hormones) alters the brain, rendering it identifiably male.
estrogens
Variety of sex hormones responsible for the distinguishing characteristics of the female.
anencephaly
Failure of the forebrain to develop.
sudden infant death syndrome (siDs)
Unexplained death while asleep of a seemingly healthy infant less than 1 year old.
