Neural Development

Question 1

Anencephaly

Answer 1

Failure of anterior neuropore to close

Question 2

Spina bifida

Answer 2

Failure of posterior neuropore to close

Question 3

Formation of Nervous System

Answer 3

Neural plate –> neural grove –> neural tube

Question 4

4th Week

Answer 4

Primary Vesicles
Forebrain (prosencephalon)
Midbrain (mesencephalon)
Hindbrain (rhombencephalon)
Spinal Cord

Question 5

5th Week

Answer 5

Secondary Vesicles
Forebrain (prosencephalon): Cerebral Hemispheres (telencephalon)
Thalamus & Hypothalamus (diencephalon)
Midbrain: (mesencephalon)
Hindbrain (rhombencephalon)
Spinal Cord

Question 6

9th Month

Answer 6

Developed Brain

Question 7

5th Month

Answer 7

Development of convolutions and sulci

Question 8

6th Month

Answer 8

6 cortical layers developed

Question 9

Teratogens

Answer 9

Agents capable of producing congenital abnormalities/interfering with development (infections, drugs, alcohol, environmental pollutant, radiation)

Question 10

Pre-embryonic Period and Teratogens

Answer 10

Toxic agents interfere with all cells and results in death

Question 11

Embryonic Period and Teratogens

Answer 11

As this is the time of tissue/organ differentiation, there is extreme sensitivity to teratogens and results in most severe functional and morphological deficits

Question 12

Fetus and Teratogens

Answer 12

Little differentiation of tissues, less vulnerability to effects of teratogens; decreased cell size and number

Question 13

Cell Proliferation

Answer 13

Development of new neurons

Question 14

Cell Differentiation

Answer 14

Different types of neurons generated

Question 15

Cell Migration

Answer 15

Neurons travel to ultimate location in CNS. Develops in an inside-out function with deeper layers produced first

Question 16

Synaptogenesis

Answer 16

Creation of synapses with other neurons and the increase in the complexity of dendritic trees and number of dendritic spines

Question 17

Selective Cells Death

Answer 17

As particular brain areas develop, they loss synapses in order to create circuits that are most effective/efficient

Question 18

Myelination

Answer 18

Starts with most primitive areas and extends to more complex areas (spinal cord and brain stem first followed by midbraind and diencephalon and then telencephalon)

Question 19

Prenatal Development

Answer 19

Primarily genetically-determined structural development; largely experience independent; sequence of development varies little among individuals

Question 20

Postnatal Development

Answer 20

Dramatic increase in the role of experience in neural development; largely experience dependent

Question 21

Reticular Activating System (Brain Stem)

Answer 21

Functioning at birth; serves vital life functions: breathing, heart rate, blood pressure, etc; role in alertness and consciousness

Question 22

Diencephalon (Thalamus, Hypothalamus)

Answer 22

Functioning at birth; regulates internal environment/needs (hunger, sleep)

Question 23

Limbic system (Amygdala, Hippocampus)

Answer 23

One of first to develop prenatally, but neurogenesis continues postnatally; close relationshipp between limbic and hypothalamus

Question 24

Auditory System (Ear to Heschl’s gyrus)

Answer 24

Mechaical aspects reasonably mature at birth but not finished myelinating until 4

Question 25

Visual System (Retina to Calcarine Fissure)

Answer 25

Fovea not finished developing until after birth and visual cortex develops rapidly during first year

Question 26

Somatosensory System (Skin/muscle receptors to postcentral gyrus in parietal lobe)

Answer 26

Thermal, tactile and positional information (crucial for infant's early exploration of the world by touch)

Question 27

Pyramidal Motor System (Precentral gyrus in frontal lobe to muscles)

Answer 27

responsible for initiation of voluntary, rapid, precise control of extremities

Question 28

Extrapyramidal Motor System (basal ganglia & cerebellum)

Answer 28

Responsible for alteration and adjustments in posture and coordination of movements initiated by the pyramidal system

Question 29

Motor System

Answer 29

Locomotion and manipulation abilities develop throughout childhood with increased ability associated with integration of both motor systems

Question 30

Association Areas

Answer 30

Cortical area where information from other areas is integrated

Question 31

Commissural - Interhemipheric Pathways

Answer 31

Transmit refined information from one side of brain to the other - integrative function; late development postnatally

Question 32

Critical Period

Answer 32

Developmental windows during which specific brain areas are developing and associated functions are emerging; genetically-determined periods of rapid neural development

Question 33

Plasticity

Answer 33

Capacity of brain to adapt or change after environmental stimulation

Question 34

Focal Injury

Answer 34

Circumscribed brain area is affected (hemispherectomy); better when younger

Question 35

Diffuse Injury

Answer 35

Whole brain is effected (TBI, toxic exposure); better when older