ch 2 child devel

cerebral lateralization

regions in the right and left hemispheres likewise have specialized functions

left hemisphere

largely involved in language

contralateral organization

the left hemisphere processes sensory information from the right side of the body and controls movements of the right side, and vice versa

limbic system

collection of brain structures involved in emotions and memory; the limbic system consists of the hippocampus, amygdala, and cingulate cortex

hippocampus

memory center, sending information to the cerebral cortex for storage and retrieval

amygdala

plays a pivotal role in the “fight or flight” response and memory

cingulate cortex

receives and relays information from and across regions of the brain and is also involved in emotion formation and memory

hypothalamus

center involved in the experience of emotions such as happiness, sadness, anger, and exhilaration

thalamus

relays information to and from the spinal cord and between the two hemispheres

basal ganglia

a cluster of nerve cells, surrounds the hypothalamus and is involved in movement

midbrain

the uppermost region of the brainstem, controls some reflex actions and is involved in vision, hearing, movements, and sleep-wake cycles

brainstem

part of the brain consisting of the midbrain, the pons, and the medulla oblongata; the brainstem controls the messages between the brain and the rest of the body

hindbrain

includes the cerebellum, the pons, and the medulla controls automatic functions such as breathing, digestion, heart rate, and blood pressure

cerebellum

coordinates movement, including rote movements such as walking

pons

helps relay messages between the cortex and the cerebellum and is central to sleep

axon

long, threadlike fiber that extends out from the cell body. Electrical impulses travel down the axon from the cell body to axon terminals

axon terminals

where neurotransmitters are released to send signals to other neurons

dendrites

are fibers that receive signals from other neurons and transmit signals to the cell body and down the axon

synapses

microscopic separations between axon terminals and dendrites

glial cells

surround and protect neurons and are involved in a number of vital brain functions

fmri

person lies motionless inside a scanner that magnetically detects regions of increased blood flow and oxygen metabolism in the brain while the person processes certain stimuli or engages in other mental activity

eeg

enables analysis of the stability, organization, and timing of brain wave patternsm

meg

offers more precision than EEG in establishing the location of brain activity

peg

person is injected with or inhales a radioactive substance that then circulates in the blood. The person then lies on an apparatus with a radiation-detecting scanner, enabling measurement of changes in blood flow in areas of the brain in response to specific stimuli

nirs

thin, flexible optical fibers are attached to a person’s scalp, and invisible, infrared light is beamed at the outer surface of the brain as the brain responds to stimuli, blood flow and oxygen metabolism changes in the brain provide a computerized, moving picture of the brain’s active areas

neurogenesis

refers to the proliferation of neurons through cell division (mitosis). Neurogenesis begins around the third or fourth week of prenatal life

migration

some cells become nerve cells and others become different types of cells, such as muscle cells and skin cells

synaptogenesis

the process by which neurons form synapses with each other

arborization

the growth and branching of dendrite “trees”—makes extensive synaptogenesis possible and enhances a neuron’s capacity for forming synapses

myelination

the formation of an insulating myelin sheath around the axons of neurons that allows signals to travel down the axon more quickly

apoptosis

the death of neurons, and the consequent elimination of their synapses, refer to the “use it or lose it” selection process of synaptic pruning as “neural Darwinism”

brain plasticity

the brain’s capacity to be shaped by experience

experience-expectant plasticity

ability of the brain to adapt in response to sensory informatione

experience-dependent plasticity

refers to changes in brain wiring that occur in response to a person’s unique personal experiences

critical periods

times when specific experiences would result in permanent changes in the brain that could never be altered

sensitive periods

refer to times in development when the brain is most susceptible to experiences, but changes are still reversible

BRAIN initiative

aims to provide scientists with opportunities to map brain circuits, measure patterns of electrical and chemical activity in those circuits, and understand how brain processes in children affect and are affected by their emerging skills

epigenetics

dandelion children

who seem able to flourish despite adverse environmental conditions

orchid children

who seem to wilt in the face of any environmental challenge