The First Years of Life
The brain region doubles its volume in the first 90 days after birth and helps babies learn motor skills.
What is the cerebellum?
humans are born with (more/less) developed brains than than other animals
less!
Rather than developing more fully in the womb or egg, human brains grow and develop extensively after birth.
This adolescent behavior, influenced by changes in the brain's reward systems and the balance between the frontal and limbic brain regions, increases learning but also risk-taking.
What is sensation seeking?
TRUE OR FALSE: brain plasticity only occurs during critical periods, and stops in the adult brain.
FALSE!
Using a technology called two-photon imaging, scientists can observe living neurons in animals with a microscope and track their growth after various experiences. Results have indicated that some plasticity occurs not only during critical periods but also during adulthood — apparently, our brains are always changing in response to our experiences.
By this age, a child’s brain reaches about 90 percent of its adult size.
(Bonus points: at what age does a squirrel monkey's brain reach its adult size?)
What is 5 years old?
(Squirrel monkey brains reach their adult size at 6 months old)
Evolutionary advantage for being born with a less-developed brain
What is adapting to our surrounding environments?
The process where stronger brain connections beat out weaker ones during adolescence.
What is competitive elimination?
Definition of plasticity.
What is the ability of the brain to modify itself and adapt to environmental challenges, including sensory inputs.?
The reason why "white matter" looks white.
(hint: there is certain a cell type that does something to cause this)
What is myelination?
Oligodendrocytes (a type of glial cell - aka neural support cell) wraps around nerve fibers to insulate them.
1. Term describing the number of connections (or synapses between neurons)
2. Neuronal process during early postnatal life when weaker connections are removed to refine and shape brain circuits.
1. What is synaptic density?
2. What is synaptic pruning?
This large bundle of myelinated fibers connects the brain's right and left hemispheres and grows during adolescence.
What is the corpus callosum?
This type of plasticity integrates common environmental stimuli, like hearing language or seeing faces, during critical periods of development.
What is experience-expectant plasticity?
The percentage by which the number of neurons in the cortex increases during the first three months of life.
(Bonus points: what is the technical terminology for the process of neuronal cells 1. growing and 2. maturing?)
What is 23 to 30 percent?
(1. cell growth = proliferation 2. cell maturation = differentiation)
Sensory experiences provided by parents that help shape a baby’s brain connections.
What are seeing parents’ faces, hearing their voices, and being held in their arms?
This brain region is the last to develop (hint: develops in 20-somethings and is important for executive functioning)
(Bonus points: In which brain regions does myelination heavily occur during childhood vs. adolescence/early adulthood?)
What is the frontal lobe?
(During early life, myelination is found in the visual, auditory, and limbic cortices. Closer to age 30, the frontal and parietal neocortices become more myelinated, which helps with working memory and higher cognitive functions.)
The brain changes resulting from non-universal experiences, such as a violinist’s enhanced cortical development for finger control, are an example of this type of plasticity.
What is experience-dependent plasticity?
The average weight of a newborn human baby’s brain.
(Bonus points: How does this compare to the average weight of an adult brain?)
What is 370 grams or 13 ounces?
(an average adult brain is 3 pounds with about 86 million neurons!)
Span of time during which toddlers experience high rates of learning (like speaking multiple languages)
What is a critical period
Two research imaging techniques commonly utilized to study how adolescent brain structure and activity change overtime.
(Bonus points: Describe the study that was done to compare the changes in white and gray matter in healthy vs. non-healthy teenagers. Specifically: which imaging techniques were used, and what were the key findings?)
What are magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI)?
(Studies using MRI to measure brain volume and DTI to study quality of white matter show that adolescents who used alcohol had reduced gray matter volume and reduced white matter integrity. Additionally, fMRI showed that binge drinking during adolescence was associated with lower brain activity, less sustained attention, and poorer performance on a working memory task.)
Young birds that do not hear this environmental stimulus before sexual maturation will not learn to produce accurate bird calls.
(Bonus points: What type of plasticity is this describing?)
What are the sounds of adult finch songs?
(This example of experience-expectant plasticity.)