CEREBRAL LATERALITY: RIGHT BRAIN/LEFT BRAIN

CEREBRAL LATERALITY: RIGHT BRAIN/LEFT BRAINDominant brain and dumb brain

SPLIT-BRAIN RESEARCH Split-brain surgery:

when the corpus callosum is cut to reduce severity of epileptic seizures

Has shown that right hemisphere controls the left side of the body and vice versa

SPLIT-BRAIN RESEARCH Roger Sperry and

Michael Gazzaniga studies

Showed language is housed in the left hemisphere

Right hemisphere: visual-spatial tasks (colors, arranging, recognizing)

HEMISPHERIC SPECIALIZATION IN THE INTACT BRAIN Perceptual

Asymmetries: left-right imbalances btwn cerebral hemispheres in the speed of visual or auditory processing

Studied to show which hemisphere is more dominant in certain situations

HEMISPHERE SPECIALIZATION

Better at: Verbal processing Language, speech,

reading, writing Possible: handling

emotions, links to schizophrenia

Better at: Nonverbal

processing Spatial, musical, and

visual recognition Possible: expression

of emotions, recognition of other’s emotions; classical conditioning, links to depression

LEFT HEMISPHERE RIGHT HEMISPHERE

ENDOCRINE SYSTEM Glands that secrete

chemicals (hormones) into the bloodstream that help control body functioning

30 different hormones

Hypothalamus controls the endocrine system

ENDOCRINE SYSTEM Hypothalamus

connected to the… Pituitary gland:

releases variety of hormones that fan out in the body, stimulating actions in other endocrine glands

Pituitary gland is the “master gland” of the endocrine system

HEREDITY AND BEHAVIORBehavioral genetics: interdisciplinary field that studies the influence of genetic factors on behavioral traits

CHROMOSOMES AND GENES Chromosomes: strands

of DNA molecules that carry genetic info.

46 chromosomes (23 pairs, 1 chromosome from each parent)

Each chromosome contains Genes: DNA segments that serve as the key functional units in hereditary transmission

CHROMOSOMES AND GENES Homozygous

condition: two genes in specific pair are the same

Heterozygous condition: 2 genes in a specific pair are different

When heterozygous, the dominant gene is expressed

GENOTYPE VS. PHENOTYPE Genotype: a

person’s genetic makeup

Phenotype: ways in which a person’s genotype is manifested in observable characteristics

POLYGENIC INHERITANCE Polygenic traits:

characteristics that are influenced by more than one pair of genes

Most human characteristics are polygenic

RESEARCH METHODS FOR INVESTIGATING HEREDITARY INFLUENCE

Family studies: examining blood relatives to see how much they resemble one another on a specific trait

Shows traits that “run in the family”

Only correlative

RESEARCH METHODS CONTINUED Twin studies:

comparing the resemblance of identical and fraternal twins w/respect to a trait

Identical (monozygotic) twins: one zygote, split

Fraternal (dizygotic) twins: 2 eggs fertilized by different sperm cells, 2 separate zygotes

RESEARCH METHODS CONTINUED Adoption studies:

examining resemblance btwn adopted children and both their biological and adoptive parents

Usually done only with babies given up at birth

GENETIC MAPPING Def: process of

determining the location and chemical sequence of specific genes on specific chromosomes

Technology only allows for single gene mapping

Most human traits are polygenic