D.P. brain development

parietal lobe

important for spatial processing. It is also involved in the integration of information from different sensory modalities, and it plays a role in integrating sensory input with information stored in memory and with information about internal states

neuron

(1) a cell body, which contains the basic biological material that keeps the neuron functioning; (2) dendrites, fibers that receive input from other cells and conduct it toward the cell body in the form of electrical impulses; and (3) an axon, a fiber (anywhere from a few micrometers to more than a meter in length) that conducts electrical signals away from the cell body to connections with other neurons.

CNS development

-There is an overproduction of dendrites and axons which results in in subsequent elimination or "pruning" - brain gets to a point where it doesn't need all this density of pathways, starts eliminating pathways that are useless and never used. -Over development, this happens in different areas of the cortex. For example, the back (occipital) area undergoes these changes in the first two years in contrast to the prefrontal cortex that changes during late adolescence. - starts in occipital, then temporal and eventually prefrontal -During the first two years, there is a significant amount of pruning Does this mean early stimulation is critically important for infants? • Not because not a significant change in environment, has to be dramatic difference. In order for pruning to occur, child only has to be in a relatively normal environment Small differences among normal environments will not affect pruning For example, parents reading books These more subtle environmental differences affect the chemistry of the brain not its basic structure

cortex

-produces abstraction of general patterns over many experiences, develops faster than hippocampus

neurogenesis

-the proliferation of neurons through cell division, begins 42 days after conception (in humans) and is virtually complete by the midway point of gestation. - does not always occur, however: it can be inhibited by stress -not fixed and predetermined but is instead adaptive, increasing under rewarding conditions and decreasing in threatening environments

developing brain

-when you look at why kids are developing and getting smarter, have to look at learning development but also look at brain development. Can't approach 6 year old and talk about theories because they are limited by brain development Significant changes occur all through development - up until 20 years old continue to develop. During certain ages particular brain regions undergo development. Pre frontal are for example develops from childhood to 20's. These changes are most dramatic during infancy but continuing until adulthood • Most dramatic time of brain development is birth to age 3. This is why newborns have reflexes and can't do much vs. 3 year old joking and conversating with parents because of brain development.

cerebral cortex

80% of the human brain, a much greater proportion than in other species -folds and fissures that are apparent during development as the brain grows within the confined space of the skull; these convolutions make it possible to pack more cortex into the limited space. - develops throughout childhood - carries out actual thought processes from info brought to different lobes

brain maturation

Beginning around 2 months there is a significant increase in dendritic branching • To communicate we have to have pathways to send signals. For airplanes, trains, etc, you have to have paths and same with pathways in the brain, to communicate across brain you need a pathway to get there or else two parts can't communicate. Happens by having neurons, axons get longer until two neurons find eachothers, the brain sends out chemical feelers to help them find each other. One pathways formed, they're there. There are pathways that are different, we know that people with autism don't have as many pathways. They are genetically determined because for object recognition we use right temporal lobe, etc. and use language in left temporal. The reason our brains are the same is because genetics have a template and tell brain how to hook up. Also, the brain has spots in the brain with options to reroute aka the synapse, to switch paths. So when talking about developing and learning, there is one that teaches basic pathways to lay down which is genetic with some degree of experience effecting it, but most of learning is synapse changing to send signals to different parts and have a chemical change, not actual tracks changing. You're born with most of neurons for rest of life, but what neurons can do is send out dendrites to make more and more connections to make more tacks. each neurons grows more dendrites for more interconnections like a forest thickening. Neurons are trees, trees has limited limbs and through time they build more and more limbs so forest looks more dense, giving an advantage because If a squirrel wants to go limb to limb, will explore faster and easier if there are more limbs, if not enough limbs there pathways are limited. Essentially want to have brains with a lot of pathways.

limbic system

Part of brain with physiological of emotions and motivations. When angry, we have physiological response (heart rate, blood pressure) the thought process of why mad is upper brain, cerebral cortex. -This is fully developed 2-3 months before birth, so newborns feel pain. Before used to think wasn't developed so they thought newborns didn't feel pain thinking pain is cognitive but this suggests the physiological response to pain is there. includes: hippocampus, hypothalamus , amygdala, and pituitary gland

myelination

Significant increase in Myelin • The brain is just millions of neurons sending signals, neurons have coming of myelin that speeds up the impulse of the neuron. Negative ions on outside and positive inside to depolarize making signal jump node to node through the nodes on renvier one of the main things happening in this area is neurons becoming myelinated. In first 2/3 years of life isn't highly myelinated and becomes myelinated so it takes less time to process more info if you think about software like knowledge and thinking, if militated it will be able to think of more complex ideas or think about more things faster. This is part of why kids get smarter - starts before birth and occurs until early adulthood

brain stem

Subcortex, physiological processes; sleeping, breathing, etc. fully developed at birth. includes: medulla, reticular formation and thalamus

plasticity

The capacity of the brain to be molded or changed by experience, referred to as plasticity, means that less information needs to be encoded in the genes. This economizing may, in fact, be a necessity: the number of genes involved in the formation and functioning of the nervous system is enough to specify only a very small fraction of the normal complement of neurons and neural connections.

last to mature

The last area of the cortex to mature is the prefrontal cortex, which is vital for regulating attention, controlling impulses, foreseeing consequences, setting priorities, and other executive functions

glial cell

Until recently, it was believed that glial cells outnumbered neurons 10 to 1. However, with the advent of new methods of cell counting, recent studies suggest that the glial cells and neurons actually appear in equal numbers -perform a variety of critical functions, including the formation of a myelin sheath around axons, which insulates them and increases the speed and efficiency of information transmission. -play a key supportive role in promoting brain health. They function as neural stem and progenitor cells during brain development

temporal lobe

associated with memory, visual recognition, speech and language, and the processing of emotion and auditory information.

corpus callopus

a dense tract of nerve fibers that connects them. The two hemispheres are specialized for different modes of processing, a phenomenon referred to as cerebral lateralization. -if you pick up a hot pot with your right hand, it is the left side of the brain that receives the sensory response, registers the pain, and initiates the motor response to let go immediately.

interneuron

act as intermediaries between sensory and motor neurons

synaptogenesis

each neuron forms synapses with thousands of others, resulting in the formation of the trillions of connections referred to earlier.

synapse

microscopic junctions between the axon terminal of one neuron and the dendritic branches of another.

white/gray matter

myelinated portions of axons are white, leading to the term white matter, and lie below the gray matter (cell bodies) at the surface of the cortex.

occipital lobe

primarily involved in processing visual information

synthesis

the blending of different types of sensory input—because the functional connections between sensory areas have yet to be pruned

frontal lobe

the brain's "executive," is involved in cognitive control, including working memory, planning, decision making, and inhibitory control

sensory neuron

transmit information from sensory receptors that detect stimuli in the external environment or within the body itself

motor neuron

transmit information from the brain to muscles and glands

humans brain birth, 6 yrs, 14 yrs

• At 6 years, very dense and then pruning occurs so by age 14 much less dense • Maturation, growth, pruning • Development roughly going back to front and top to bottom but not exact because there are still some spots in front d=for example developing which helps explain why as kids get older skills change

what determines pruning

• Pathways are genetic for example genetics know we will want to go from Pittsburgh to California, but we don't know exactly where in Pittsburgh to where California so pruning occurs with what paths get used the most for example Pittsburgh to LA get used a lot. When paths aren't used, then we get rid of it, maintain what is used. Pruning depends on experience, if experience determines pathways so if babies have a lot of experience they will have lots of pathways and make them smart. But brains have to be efficient and having a lot of pathways it doesn't really need isn't efficient. Also, what type of experience causes a path to be pruned away, but turns out little slight experiences don't effect it. Giving a kids flash cards, etc won't do anything. Pruning is only effected by huge environmental differences. For example the sight area of brain only needs sights exposure, only would be effected if blinded. Same with language area, if you don't use Chinese languages, won't need those paths any more so if becomes more efficient for your native English language, this is pruning. So having big brains and lots of pathways isn't an advantage, children with autism actually have larger brains because of this. Only major changes impact pruning. Little changes like number of vocab, being read to, won't effect pruning this is just synapse changing and chemical reactions.