psych content week of feb 1st

autism

polygenic and due to unexplained genetic factors

behavior genetics main type of study

family study to see behaviors of people with varying relatedness and see how nurture plays a role

ERP

best method for looking at brain activity for young kids

___% of deaths of kids under 5 worldwide is due to

undernutrition

Apgar scoring system for determining fetal health

activity, pulse, grimace (reflex), appearance (pink vs blue), respiration

low birth weight

under 5.5 pounds

premature

born at under 35 weeks

newborns spend time doing

crying, quiet sleeping, active sleeping, drowsing, alert awake, active awake

Individual differences with parent-infant interactions can impact aspects like bonding and learning

Rapid eye movement (REM) sleep

Stage of sleep characterized by intense brain activity and vivid dreaming, which help infants get visual stimulation even while asleep, since they do not spend a lot of time awake

genome

each person's complete set of hereditary information

Chromosome

long threadlike molecule made up of two twisted strands of DNA

DNA

strands/sections of the chromosomes that contain genetic instructions for making proteins for the development of life

genes

segments of DNA that code for a specific protein

Regulator genes

protein that controls the expression of other genes; turns genes on and off

alleles

variants of genes that cause different phenotypes

sickle cell anemia

Dominant is a normal donut shaped red blood cell that flow freely within the blood vessel

Recessive is a sickle/crescent moon shaped cell that blocks blood flow in the vessel

This can result from a single gene mutation

BRCA1 and BRCA2 (breast and ovarian cancer)

Mutations of BRCA1 or BRCA2 can make someone more susceptible to breast cancer and ovarian cancer

Founder mutation

a genetic alteration observed with high frequency in a group that is or was geographically or culturally isolated, in which one or more of the ancestors was a carrier of the altered gene. This phenomenon is often called a found effect or founder variant

MAOA

Young men with an inactive MAOA gene (nature) and severe maltreatment (nurture) have the worst outcomes in terms of antisociability

deficit framework

the diathesis stress model, in which vulnerability + stress leads to disorder

looks at susceptibility to differences, sometimes those with the same characteristics do the worst and also the best

epigenetics

alterations to DNA, other than changes to the genes themselves; caused by experiences

Histones are wrapped in DNA

Methylation: more tightly wrapped and affects gene expression

Acetylation: less tightly wrapped and affects gene expression

Identical twins have the same genes but different expressions

Behavior genetics

concerned with how variation in behavior and development results from the variation of genetic and environmental factors

Heritability of IQ:

As people age, heritability becomes stronger due to the ability of people to choose and shape one's environment... so environment changes, which means observed differences are more due to genetics (increased heritability)

prenatal brain development

Forebrain: cerebral hemisphere and thalamus

Midbrain: emergence of the cerebellum

Brainstem/hindbrain: medulla, pons

parietal lobe

processes somatosensory info and spatial awareness

Frontal lobe

controlling complex behaviors, voluntary movement, language production, and executive functions like planning, decision-making, and emotional regulation.

cranium

the baby's cranium is usually very stretched out right after birth

Fontanelles: soft spots in the baby's cranium

Neurogenesis

the proliferation and rapid increase of neurons through cell division

Two ways the brain changes: how neurons are connected/disconnected to/from each other

Synaptogenesis

the process by which neurons form synapses with other neurons, resulting in trillions of connections

Synaptic pruning

the normal developmental process through which synapses that are rarely activated are eliminated

Synaptic density is highest in the first year after birth, and then gets less with age

Atypical patterns of pruning have been implicated in autism and schizophrenia

Myelination

the formulation of a fatty sheath called myelin around the axons of neurons. This forms the white matter that is under the gray matter

Gray matter: cell bodies

Its slow, but with time, grey matter decreases and white matter increases

first to develop

hippocampus

last to develop

frontal lobe and prefrontal cortex

plasticity

the brain's capacity to be molded by experience

Experience-expectant plasticity

normal wiring as a result of experiences humans typically will have

the brain expects a particular environment (ex: expects to learn a language)

Advantage: less needs to be hard-wired

Disadvantage: vulnerability when the expected outcome does not occur

Hubel and wiesel study

suture one eye closed in kitten vs cat. The kittens were more likely to have the other eye take over, and when the sutured eye was opened, that eye was functionally blind. When adult cats had the sutured eye opened, they went back to seeing normally

Experience dependent plasticity

wiring as a result of an individual's experiences

Changes in brain structure due to an individual's particular experience

Rats in enriched environments had more dendrites and synapses, more glial cells, and better learning abilities

Cerebral lateralization

hemispheres control different functions

Left hemisphere: language, timing

Right hemisphere: spatial processes, pitch

Neuromyth: left vs right brained people; this is not a thing. Some people have strength in certain areas, but we are all using both hemispheres of the brain as they are very interconnected

Secular trends

changes in physical development that have occurred over generations, such as height and start of menstruation

SES and the brain

Individual differences, especially across SES, can affect total gray matter in the brain

Breast milk can be very healthy for a child, but ability to breast feed can depend on SES and access to resources, as well as ability to take on the financial/physical toll that comes with breastfeeding

Random assortment

of chromosomes in the formation of egg and sperm promotes variability among individuals. During gamete division, the 23 pairs of chromosomes are shuffled randomly, with chance determining which member of each pair goes into a new egg or sperm

Crossing over

causes further genetic variation; when gametes divide, the two members of a pair of chromosomes sometimes swap sections of DNA. As a result, some of the chromosomes that parents pass on to their offspring are constituted differently from their own

Polygenic inheritance pattern

many different genes contribute to a given phenotypic outcome. These involve traits that have many genes that contribute to individual differences

PKU

a disorder related to a defective recessive gene on chromosome 12. People with this disorder cannot metabolize the amino acid phenylalanine

causing impaired brain development and intellectual disabilities if eating a normal diet, but can be fine if eating a certain diet

Quantitative genetics research designs

Uses stats to study naturally occurring genetic and environmental variation by comparing phenotypes of individuals who vary in the amount of genomic DNA they share

Molecular genetics research designs:

Examines specific DNA sequences to find mechanisms that link genes and behavior and see how DNA variation causes behavioral variation

This helps look at genetic influences in large samples of unrelated people, and understand genetically based developmental disabilities

Glial cells

perform a variety of critical functions, including myelin sheath formation around axons, protect the brain in the case of injury, aid in regeneration, and function as neural stem and progenitor cells during prenatal development

Cerebral hemispheres

the cortex is divided into two hemispheres, and sensory input from one side of the body goes to the opposite hemisphere

Corpus callosum

a dense tract of connective nerve fibers between

Arborization

an enormous increase in the size and complexity of the dendritic tree that results from growth, branching, and the formation of spines on the branches. This increases dendritic capacity to form connections with other neurons

Because of arborization, neurons grow in complexity over the first several years of postnatal life, and the cortex grows in surface area and the layers become thicker

Cross modal reorganization

for example, visual impairments tend to be correlated with recruitment of auditory areas instead. This occurs when experiences that are species-typical are absent, so the brain reorganizes

Sensitive periods

during these, the brain is especially sensitive to specific external stimuli. Neural organization occurring or not occurring during a sensitive period is usually not reversible

benefits of breastfeeding

Breast milk is free of bacteria and contains the breast-feeding antibodies against infectious agents the baby is likely to encounter

Breast feeding decreases the mother's risk of breast and ovarian cancer

Fatty acids in the breast milk have a positive effect on cognitive development likely because of increased myelination in breast fed infants, so info transmission is more efficient

flavors

Sweet and savory flavors produce positive facial responses across ages, while bitter flavors elicit negative responses

Sour flavors have varied responses among infants, and salt does not usually produce much of a reaction until after 4 months when a preference for salt emerges

Food neophobia

an unwillingness to eat unfamiliar foods, common as babies switch from liquid to solid diet. To overcome this, repeatedly introduce new foods to babies and have them taste it

Genetic factors of weight

the weight of adopted children are more correlated with their biological parents, and identical twin weights are more similar than fraternal ones

Food deserts

residents rely on convenience stores that stock primarily high calorie pre-packaged foods

undernutrition

Increases a child's risk of developing infections, and these illnesses may decrease ability to take in nutrients, leading to a vicious cycle of infection and undernutrition