behavior genetics
an interdisciplinary field that studies the effects of genes and environment on behavior
asks whether traits are heredity or inherited
identifies genes responsible for traits
asks if the environment determines traits
the genome project
-identified all the genes in many species
-identified the code for all of the genes in humans and other species and created a catalog
-addressed ethical, legal, and social issues that arise from the project
23
how many pairs of chromosomes do we have?
how do you inherit genes?
you inherit one of each chromosome pair from your parents ova and sperm
genotype
based on the gene pairs(alleles)
-the gene combination that determines the outward expression of a trait (normal and abnormal)
phenotype
the observable manifestation of a trait
-can be physical or behavioral
alleles
a gene pair
homozygous
same gene on both chromosomes from parents
heterozygous
different gene on both chromosomes from parents
proteins
genes are the template used to produce what?
recessive trait
~a trait that must be contributed by both parents in order to appear in the offspring.
~Recessive traits can be carried in a person's genes without appearing in that person.
~For example, a dark-haired person may have one gene for dark hair, which is a do
dominant trait
a trait that will appear in the offspring if one of the parents contributes it.
lateralized
found on one side of the brain or the other
temporal lobe
auditory information, visual patterns, speech, face and work recognition, memory formation
occipital lobe
vision
hippocampus
forming new memories
electrical potentials/EEG
summed electrical activity of the brain (fast changes in brain function, resolution depends on spacing between electrodes
The EEG- Electrical Activity
summed electrical activity of the brain
CAT (computerized axial tomography scan)
-uses X-rays
-Produces stationary high resolution images of the brain
PET (positron emission tomography)
uses radioactively labeled
compounds that brain cells use (glucose, oxygen or a drug)
Produces high resolution images of brain function over prolonged times
MRI (magnetic resonance imaging)
uses the interaction between
magnetic fields and the brain's electrical activity
Produces high resolution stationary images of the brain
fMRI
tracks blood flow; measures oxygen levels. High oxygen blood flow
near = active brain cells
Produces high resolution images over very short times.
central nervous system
BRAIN + SPINAL CORD
peripheral nervous system
ALL OTHER NERVES that transmit information to and from the central nervous system
sensory neurons
PROVIDE INPUT FROM THE ENVIRONMENT TO THE CENTRAL NERVOUS SYSTEM (CNS)
~From sensory receptors to the brain & spinal cord
motor neurons
PROVIDE OUTPUT FROM THE CNS TO MUSCLES AND GLANDS
~Mediates the ability to respond to sensory stimuli. Move hand away from painful stimulus
interneurons
Communicate information between sensory and
motor neurons
� Most numerous neurons in the central nervous system
glia
~More numerous than neurons
~Provide nutrition & act as structural support
~Insulate parts of the neuron
~Remove dead or damaged cells
~Provide a blood brain barrier keeps bacteria and viruses from infecting the brain
the cell body
central hub,
contains the cell's nucleus
nucleus
� Centrally located in the cell body
� Contains DNA and chromosomes
� Directs metabolism
� Provides energy for the neuron to function
dendrites
Receive inputs and information from neighboring neurons
~inputs may number in thousands
ion
a molecule that has a positive or negative charge
depolarization
The bigger the stimulus - the more sodium channels
open - the more sodium ions flow into the cell - the
more positive the inside of the cell becomes
proteins
genes are the template used to produce what?
X
recessive traits are located on what chromosome?
X
X-linked, or sex-linked traits are located on what chromosome
frontal lobe
in charge of executive functions, social behavior
primary motor cortex
controls voluntary movement (on frontal lobe)
somatosensory cortex
receives info about body sensations (on parietal lobe)
primary auditory cortex
processes auditory information (on temporal lobe)
primary visual cortex
processes visual information(on occipital lobe)
association areas
(on all four lobes) combine sensory and motor information; coordinate interaction among different brain areas
temporal lobe
auditory information, visual patterns, speech, face & work recognition, memory formation
left cerebral cortex
where are Broca's and Wernicke's areas in the brain?
lower frontal lobe(production of speech)
~can't speak
where exactly is Broca's area?
temporal lobe (comprehension of written or spoken language)
~can speak, but only non-sense
where exactly is Wernicke's area?
occipital lobe
portion of the cerebral cortex lying at the back of the head; visual areas
parietal lobe
portion posterior to the frontal lobe, responsible for sensations such as pain, temperature, and touch
sulci
shallow grooves that separate gyri
gyri
elevated ridges on cortical surface of the cerebral hemisphere, which increase the surface area and provide space for additional cortical neurons
hypothalamus
links brain and endocrine system; regulates hunger, thirst, sleep, and sexual behavior, circadian rhythms
corpus callosum
the major pathway connecting the 2 hemispheres; contains axons/connections of neurons between the right and left side of the brain; why
thalmus
processes and integrates sensory information; relays sensory information to cerebral cortex
amygdala
involved in memory and emotion, especially FEAR and anger, interpret facial signals of others
hippocampus
memory formation
medulla
vital reflexes (breathing, heart rate, digestion, etc)
cerebral cortex
where the human brain has the most devoted to
central and peripheral
nervous system is divided into what 2 systems?
dermatomes
provide a map of the body form the peripheral nerves that exit the spinal cord at different levels. Their output is related to a map of the body in the somatosensory cortex
neurons
basic units of the nervous system
~have a cell membrane and a cell body with nucleus
sympathetic nervous system
signal glands to produce arousal; allows you to interpret a dangerous situation and move away from it
parasympathetic nervous system
signal glands to produce relaxation; calms you down after sympathetic system has aroused you
cell body
processes nutrients and provides energy for neuron; central hub of every cell, contains cell's nucleus
nucleus
contains DNA & chromosomes
centrally located in cell body
directs metabolism
provides energy for the neuron to function
dendrites
receive information from other neurons and sensory receptors
axon
takes information and carries it to other neurons, muscles, and glands
~wrapped by glia cells with a substance called myelin
nodes of ranvier
gaps in the myelin sheath
myelin sheath
insulates axon and increases communication speed