Chapter 8: Development of the Nervous System

Question 1

Poverty’s affect on brain development

Answer 1

inhibits brain growth due to family stress, greater exposure to environmental toxins, or insufficient nutrition

while higher status families might be able to provide more “cognitive stimulation” to their children.

Question 2

Development of neurons

Answer 2

Stem cell -> Progenitor Cells and migration -> Neuroblast -> Interneuron or pyramidal neuron

Question 3

Development of glia cells

Answer 3

Stem cell -> Progenitor Cells and migration -> glioblast -> olgiodendroglia or astrocyte

Question 4

Neurogenesis in the adult brain

Answer 4

Adult neurogenesis occurs throughout life in restricted brain regions in mammals.

However, the number of neural stem cells (NSCs) that generate new neurons steadily decreases with age, resulting in a decrease in neurogenesis

Question 5

Radial Glial Cells

Answer 5

Path-making cell that a migrating neuron follows to its appropriate destination

Question 6

Default network structures

Answer 6

• contributes to internal modes of cognition used when remembering, thinking about the future, and mind wandering
• The increase in connectivity between the medial regions of the frontal lobe, the posterior regions of the cingulate cortex, and the lateral regions of the parietal lobe
• the increased connectivity in the default network is related to intelligence

Question 7

Growth cones

Answer 7

• growing tip of an axon
• Directed by tropic molecules

Question 8

Filopodia

Answer 8

• process at the end of a developing axon that reaches out to search for a target or to sample the intracellular environment
• thin, actin-rich plasma-membrane protrusions that function as antennae for cells to probe their environment.
• Located on the tip of the axon

Question 9

Cell adhesion molecules

Answer 9

• On the target cell’s surface or intracellular space
• Provides surface to which growth cones can adhere
• Serves to attract or repel growth cones

Question 10

Tropic molecules

Answer 10

• Tells growth cones to “come over here”
• Likely to tell other growth cones seeking different targets to keep away

Question 11

Synaptic pruning

Answer 11

• eliminating unnecessary synapses through….
• genetic signals, experience, reproductive hormones, stress, SES, apoptosis, neural darwinism

Question 12

How does age correlate with the amount of synapses?

Answer 12

Increased age means less synapses

Question 13

Apoptosis

Answer 13

genetically programmed cell death

Question 14

Gut bacteria and behavior

Answer 14

• Many neurodevelopmental disorders, including autism, may be related to an atypical microbiome early in life
• Microbiome: bacteria in the gut with which the ENS interacts
• Psychobiotics: Treatment that uses live bacteria (probiotics) or compounds to enhance the growth of gut bacteria (prebiotics)

Question 15

Cortical gray matter density change during adolescence

Answer 15

Decreases as you get older, cortex gets thinner

Question 16

Differences between male and female brains

Answer 16

• Females reach maximum overall and gray matter volume sooner than males
• Females have a larger insula

Question 17

__________ cannot emerge until the requisite neural machinery has developed

Answer 17

• Behaviors (develop quickly through stages and are shaped significantly by epigenetic factors once the machinery is in place)

Question 18

How do stem cells know what to become?

Answer 18

Myelination, neurotropic factor, epidermal growth factor, basic fibroblast growth factor